&EPA
United States
Environmental Protection
Agency
Environmental Research
Laboratory
Athens GA 30613
EPA/600/3-87/012
October 1987
Research and Development
MINTEQA1, An
Equilibrium Metal
Speciation Model:
User's Manual
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EPA/600/3-87/012
October 1987
MINTEQA1, AN EQUILIBRIUM METAL SPECIATION MODEL: USER'S MANUAL
by
David S. Brown and Jerry D. Allison"1"
Assessment Branch
Environmental Research Laboratory
Athens, Georgia 30613
+Computer Sciences Corporation
Environmental Research Laboratory
Athens, Georgia 30613
ENVIRONMENTAL RESEARCH LABORATORY
OFFICE OF RESEARCH AND DEVELOPMENT
U.S. ENVIRONMENTAL PROTECTION AGENCY
ATHENS, GEORGIA 30613
U 3 Environmental Protection Agency,
v-v- , V ,"-r;' (5PL-16)
...... street, Room 1670
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DISCLAIMER
The Information in this document has been funded wholly or in part by
the United States Environmental Protection Agency. It has been subject to
the Agency's peer and administrative review, and it has been approved for
publication as an EPA document. Mention of trade names or commercial pro-
ducts does not constitute endorsement or recommendation for use by the U.S.
Environmental Protection Agency.
ii
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FOREWORD
As environmental controls become more costly to implement and the penal-
ties of judgment errors become more severe, environmental quality management
requires more efficient management tools based on greater knowledge of the
environmental phenomena to be managed. As part of this Laboratory's research
on the occurrence, movement, transformation, impact and control of environ-
mental contaminants, the Assessment Branch develops management or engineering
tools to help pollution control officials achieve water quality goals.
The attention of environmental decision makers is increasingly being
focused on the movement of pollutants into ground water. Of particular
importance is the transport and speciation of metals. The MINTEQA1 model is
a versatile, quantitative tool for predicting the equilibrium behavior of
metals in a variety of chemical environments. Designed for convenient use by
environmental scientists and engineers, the model should be a valuable tool
for environmental risk assessment and hazard evaluation.
Rosemarie C. Russo, Ph.D.
Director
Environmental Research Laboratory
Athens, Georgia
iii
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ABSTRACT
Recent advances in technical understanding of the processes controlling
the behavior of pollutants in the environment have led to the development of
many predictive models. MINTEQA1 is a versatile, quantitative geochemical
model for predicting the equilibrium behavior of metals in a variety of chem-
ical environments. The complex series of reactions among solution species,
gases, solids, and sorbed phases can be modeled relatively easily using
MINTEQA1. This MINTEQA1 manual is designed to acquaint new users with the
geochemical principles and mathematical formalisms involved in using the pro-
gram. A major goal is to minimize the effort unfamiliar users must expend in
acquiring an operational knowledge of this valuable environmental modeling
tool and thus promote its use in a variety of environmental risk assessment
and hazard evaluation scenarios. To facilitate this goal, an interactive
preprocessor program PRODEFA1 also is discussed. PRODEFA1 assists new users
by assembling the sometimes complicated MINTEQA1 input files automatically
in response to an on-line question and answer dialogue that places minimal
demands on potential new users. Using PRODEFA1, environmental scientists and
engineers can rapidly learn to extract many of the benefits of MINTEQA1 with-
out the initial complication of having to simultaneously learn input file
formatting details.
This report covers the period from April 1, 1986 to March 31, 1987
and work was completed as of February 1, 1987.
iv
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CONTENTS
Disclaimer ii
Foreword iii
Abstract iv
Figures vi
Tables vi
Acknowledgment vii
1. Chapter 1 - Introduction 1
2. Chapter 2 - Purpose 3
3. Chapter 3 - History of MINTEQA1 and PRODEFA1.... 5
4. Chapter 4 - Thermodynamic Principles 6
5. Chapter 5 - Getting Started 47
References 61
Appendices
A. Newton-Raphson Numerical Method 63
B. Sample PRODEFA1 Dialogue for the CaC03 Problem 64
C. The Thermodynamic Database Used by MINTEQA1 67
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FIGURES
Number Page
4.1 Constant capacitance model 34
4.2 Triple layer model 42
TABLES
Number Page
4.1 Complete list of MINTEQA1 components 7
4.2 Species types involved in a 0.001 molar CaCC>3 problem 13
4.3 Reactions among components to form complex species in a
0.001 molar CaC03 solution 14
4.4 Stoichiometric matrix representing the 0.001 molar CaC03
probl em 15
4.5 Mass action expressions applicable to the CaC03 solution
equilibria 16
4.6 Relationship between MINTEQA1 equilibrium constants for
surface complexation reactions and intrinsic constants
commonly found in the literature 40
5.1 Mineral group ID codes used in forming solids ID numbers 54
vi
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ACKNOWLEDGMENT
The authors would like to thank Dr. John Westall, Oregon State University,
Corvallis, OR, for openly sharing his wisdom on metal speciation models during
the many discussions we had at the Athens Environmental Research Laboratory.
We also extend an acknowledgment to several current and former members
of the Battelle Pacific Northwest Laboratories staff including Drs. Stan
Peterson, Bill Deutsch, John Morrey, and Everett Jenne for their helpful
guidance and suggestions on a variety of topics.
We are especially grateful for the many hours Mr. Roger Carlton, USEPA,
Region IV, and Mr. Timothy Wool and Mr. Patrick Cannon, Computer Sciences
Corporation, spent trouble-shooting the MINTEQA1 program and making PRODEFA1
operative. We also thank Roger for sharing the experience gained from several
hundred program executions representing very complex systems.
We gratefully extend acknowledgments to Dr. Nicholas Loux, Mr. Thomas
Barnwell, Mr. Lee Mulkey, and Mr. Robert Ryans, of the Environmental Research
Laboratory, Athens, GA, for their thorough and timely review comments.
A very special thanks is offered to Ms. Annie Smith of the Athens Envi-
ronmental Research Laboratory for maintaining her usual good nature and
secretarial efficiencies while typing the manuscript under pressure. Her
skills in these regards are virtually without equal.
vii
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CHAPTER 1
INTRODUCTION
Technical understanding of the physical, chemical, and biological pro-
cesses controlling the behavior of pollutants in the environment has in-
creased significantly in the past two decades. Many of the important ad-
vances are reflected in the quantitative mathematical models now being used
to describe the influences of competing processes or reactions on the overall
behavior of pollutants. A variety of mathematical models encompassing years
of research are now available for predicting behavior of pollutants in vari-
ous environmental settings. The metal speciation model, MINTEQA1, described
in this manual is a versatile, state-of-the-art example of the equilibrium
solution chemistry programs now available. The MINTEQA1 program is designed
to solve a broad range of complex chemical equilibrium problems involving
reactions among gases, aqueous solutions, mineral phases, and adsorbed phase
species with minimal demands on the user.
Included in MINTEQA1 is an extensive thermodynamic database that is
adequate for solving a broad range of problems without need for additional
user-supplied information. The standard database can be easily modified,
however, if it is found to be incomplete or inadequate for a particular pro-
blem. Thermodynamic data are not included for any of the optional sorption
algorithms available in the program. The state-of-the-art in metal sorption
research has not yet progressed to the point that thermodynamic equations of
state are available to define the complex array of competitive metal sorption
reactions expected to occur in various environmental situations.
The empirical nature of the available metal sorption data reflects the
fact that natural sorbent phases often occur as mixtures of impure, ill-
defined, interacting amorphous mineral and organic components that vary
widely in chemical behavior from site to site. For this reason, sorption
data are left to the discretion and problem-specific knowledge of the user.
Six sorption models are available in MINTEQA1 to match the quality and type
of metal sorption data available for specific problems.
An optional preprocessor program PRODEFA1, is included to assist un-
familiar users in assembling the complex input files that are sometimes
required. PRODEFA1 is an interactive preprocessor designed to lead new users
through a standard set of questions necessary to formally define the desired
chemistry problem in MINTEQA1 format. The use of PRODEFA1 frees users of the
distractions of learning component identification numbers and formatting
details. PRODEFA1 provides a liberal menu of optional help texts to assist
in learning MINTEQA1 formalisms, reviewing chemical concepts, or developing
appropriate responses to the interactive questions.
1
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Error recovery options are provided to allow partially completed input
files (and the interactive dialogue text) to be recalled and to allow com-
pleted files to be checked and edited. A number of checks also are incor-
porated to warn users of impending convergence failure resulting from impro-
per, incomplete, or over-restrictive specification of the problem being
defined.
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CHAPTER 2
PURPOSE
The purposes of this manual are manifold. One objective is to provide
new MINTEQA1 users with an outline of the many chemical and geological prin-
ciples that control chemical equilibria among electrolyte solutions, gases,
and solid phases. The treatment provided is not rigorous, however, and is
intended only as a brief review. Most of the basic chemical concepts encom-
passed by MINTEQA1 are well documented elsewhere.
The more difficult aspect of comprehending chemical equilibria is to
gain a "feel" for the complex and extensive ways these rather simple concepts
interact to determine the position of final equilibrium in solutions contain-
ing many components. Often, it is confusion about this latter issue that
limits progress in solving problems that otherwise involve relatively simple
concepts. This is also an area where assistance from computers is a welcome
and expedient alternative.
Many users will find that the greatest utility of MINTEQA1 (or other
chemical equilibrium models) is the assistance provided in isolating the con-
trolling reactions in complex systems. Ironically, these controls are typi-
cally quite amenable to desktop evaluation once isolated.
Ultimately, it is the experience gained from operating the model in both
successful and unsuccessful execution attempts that leads most quickly to an
understanding of the systems under investigation. This philosophy is not
offered in support of the blind usage of MINTEQA1 or any other model; rather,
it is meant to imply that for complex systems, trial and error may be the
best teacher. This manual, together with PRODEFA1, will allow new users to
begin this learning process with minimal initial preparation. Extensive text
entries are included in PRODEFA1 to facilitate convenient on-line reference
along the way. Frequent use of the "help" options in PRODEFA1's questioning
routine will provide an element of programmed learning.
Another objective is to familiarize users with the mathematical formalisms
used in formulating chemical equilibria problems. This is accomplished using
a series of detailed examples representing simple chemical systems likely to
be familiar to the user. These examples closely follow the clear, concise
development provided by Westall (19).
A final objective is to help users gain experience with MINTEQA1 through
modeling a few very simple systems. Example input files are provided for
several simple systems to illustrate how various chemical constraints are
accommodated in MINTEQA1. These examples will provide useful practice situa-
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tions and help users determine whether the programs are properly installed
and operational on their equipment.
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CHAPTER 3
HISTORY OF MINTEQA1 AND PRODEFA1
The MINTEQA1 equilibrium geochemical model is a late generation addition
to the REDEQL (10) family of models which has evolved over a period of more
than 15 years. The original version (MINTEQ) was developed at Battelle's
Pacific Northwest Laboratory (7) by combining the versatile mathematical
formalism from MINEQL (21) and the well-developed thermodynamic data base
from the U.S. Geological Survey's WATEQ3 model (1). With the exception of
expanded matrix dimensions, minor overrun fixes, and a substantially expanded
data base, MINTEQA1 is nearly identical to the original MINTEQ.
Because of the level of detail required to properly specify complex
chemical equilibrium problems, the development of input data files is often
tedious. This difficulty, coupled with the frustrations of having to learn
chemical component and species identification numbers, mathematical formalisms,
and formatting details, has deterred many potential users from using chemical
equilibrium modeling programs to maximum advantage. To circumvent this
problem, a series of preprocessor programs designed to simplify model usage
have evolved.
The earliest preprocessor program, MISP (6), was developed at Battelle's
Pacific Northwest Laboratory for use with MINTEQ. Lacking efficient error
recovery options, MISP was soon abandoned in favor of a much improved version
designated PRODEF (12). This new code also was developed at Battelle through
funding support from several sources (U.S. Department of Energy, U.S. Environ-
mental Protection Agency, and the Electric Power Research Institute). The
present preprocessor program, designated PRODEFA1, is identical to PRODEF in
all major respects, but incorporates many modifications and additions to the
"help" text entries including an expanded section explaining how to avoid
phase rule violations and other errors in formulating the problem. These
latter changes were incorporated at the Environmental Research Laboratory,
Athens, Georgia, to facilitate rapid on—line reference.
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CHAPTER 4
THERMODYNAMIC PRINCIPLES
Several fundamental thermodynamic principles are important in solving
geochemical equilibrium problems. This chapter provides a brief review of
these relationships with particular emphasis on the mathematical formalisms
used in MINTEQA1. For this purpose it is instructive to define several key
terms used in the program.
To provide versatility in solving a broad range of problems using a
consistent mathematical formulation, several chemical species types are
defined in MINTEQA1 and PRODEFA1. There are seven species types in all.
Types 1 through 6 are used in MINTEQA1. Type 7 is a special category used
only temporarily in PRODEFA1. All Type 7 species are redefined as Types 1
through 4. All species types are defined below. These definitions are also
a part of the PRODEFA1 help text.
SPECIES DEFINITIONS
Type 1
COMPONENTS: Basis species or "components" are aqueous species that are
chosen from the component database to represent reactants in all reactions to
be considered. Only "components" are used to represent reactants in chemical
reactions that generate other species as products. Each element in the data-
base is represented by at least one, and frequently several, components. Ele-
ments that have more than one important oxidation state must have multiple
component species identifiers. For instance, sodium is represented by the
single component Na+, but iron is represented by ¥e^+ and Fe^+ to reflect the
two predominent oxidation states.
Many components of the component database were chosen as the simple ions
(e.g., Na , Fe , Fe ) as opposed to compound species such as H/SiO/ and
113803. Compound species are used where there is a gain in mathematical
efficiency in representing the overall chemical equilibria. Ultimately, the
components were selected such that all possible species from the thermodynamic
database can be produced from a minimum set of components. This results in
minimization of the mathematical dimensions of the problem.
A complete listing of the component species available in the MINTEQA1
database is given in Table 4.1. Entering analytical concentrations of the
component species is central to setting up a MINTEQA1 modeling exercise and
often constitutes the majority of effort in preparing the input data files.
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TABLE 4.1. COMPONENT SPECIES CURRENTLY REPRESENTED IN THE MINTEQA1
THERMODYNAMIC DATABASE. THE 3-DIGIT NUMBER IS THE SPECIES ID.
ID
Number
001
002
020
030
060
061
090
100
130
140
141
142
143
144
145
146
147
148
Name
e~
H20
Ag+
Al +
H3As°3
H3As04
H3B03
Ba2+
Br~
co32~
Fulvate
Humate
Acetate
Tartrate
Glycine
Salicylate
Glutamate
Phathalate
ID
Number
150
160
180
210
211
212
220
230
231
270
280
281
330
360
361
380
410
440
Name
Ca2+
Cd2+
CL~
Cr2+
Cr(OH)2+
Cr042~
Cs+
Cu+
CU2+
F~
Fe2+
Fe3+
H+
Hg22+
Hg(OH)2
I"
K+
Li +
ID
Number
460
470
471
490
491
492
500
540
580
600
680
730
731
732
760
761
762
770
Name
Mg2+
Mn2+
Mn3+
NH4 +
N02~
N03-
Na+
Ni2+
P043-
Pb2+
Rb+
HS~
S
so42~
HSe~
HSe03~
Se042"
H/.SiO,
ID
Number
800
870
871
890
891
892
893
900
901
902
903
950
990
991
992
993
994
995
Name
Sr2+
T1 +
T1(OH)3
U3+
u*+
uo2+
uo22+
V2+
V3+
V02+
vo2+
Zn2 +
SOH1
SOH2
XPSIO
XPSIB
XPSID
SOHB
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Appendix C contains information on species nomenclature and MINTEQAl's
thermodynamic database.
Type 2
COMPLEX: A "complex" is formed from the reaction of two or more com-
ponents. The reaction below illustrates the formation of the Type 2 complex
(NaHCO-,) from the combination of three components (Na , H and C0o~~).
Na+ + H+ + CO|~ > NaHC03 4.1
Likewise, for a sorption reaction between a surface site component
(designated by SOH) and a sodium ion component, the new complex SO—Na is
formed.
SOH + Na+ > S0-Na+ + H+ 4.2
Note that a hydrogen ion component was exchanged in the reaction.
Type 2 complexes are read from the thermodynamic database and need not
be entered except in the case of complexes resulting from sorption reactions
or reactions not in the database.
Type 3
FIXED SPECIES: A "fixed species" can be any species with a fixed acti-
vity. These species are commonly one of four types: 1) components that the
user wishes to introduce at a fixed activity, such as H+ or e~, 2) solid
phases that are present in infinite supply, 3) gases that are present at a
fixed partial pressure, and 4) redox reactions between any two components.
Type 4
FINITE MINERAL: A mineral that is initially present in a finite quantity
and subject to complete dissolution during the approach to equilibrium.
Type 5
POTENTIAL MINERAL: A "potential mineral" is defined as a solid phase
that is not present initially, but which may form during chemical equilibra-
tion. If the solubility products are exceeded during the course of reaction
(equilibration), potential minerals will precipitate.
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Users should introduce Type 5 species judiciously when preparing input
data files. Introducing the complete list of all possible solids in a com-
plicated system will greatly, and unnecessarily, complicate the computations.
Only those solids that are considered likely to precipitate should be intro-
duced. Ideally, the minimal list of probable solids can be obtained by
inspecting the saturation index listings from a pilot model run that purpose-
fully prohibits precipitation.
Type 6
EXCLUDED SPECIES: An "excluded species" is an aqueous component or com-
plex, a mineral, or a gas that is in the thermochemical database, but is
excluded from the mass balance calculations. Examples are the electron and
the adsorption potentials that are treated as components in the constant
capacitance and triple—layer adsorption models.
Type 7
ADDED SPECIES: These are always either components or other species that
are not present in the thermodynamic database but are needed in the problem.
The "other" species include aqueous complexes, gas or solid phases, redox
couples, and adsorption products. PRODEFA1 initially designates all added
species as Type 7 but re-assigns each one to the appropriate type (1-5)
before entering them in the MINTEQA1 input file. MINTEQA1 treats all added
species as an addendum to the thermodynamic database.
PROBLEM FORMULATION
Chemical equilibrium problems are normally formulated in one of two ways:
1) minimization of the system free energy under mass balance constraints or
2) simultaneous solution of the nonlinear mass action expressions and linear
mass balance relationships. Van Zeggeren and Storey (18) have shown these two
approaches to be mathematically equivalent. MINTEQA1 uses the more common,
latter approach, also commonly refered to as the "equilibrium constant method".
This method also is used in several other geochemical equilibrium programs
including PHREEQE (13), EQ3NR (22), and MICROQL II (19).
In the equilibrium constant method, all applicable mass action reactions
are written using an arbitrarily selected set of input "components" (Type 1
species) as reactants. The choice of input components is not unique, but the
components must be selected such that all species (Type 2, 3, 4, 5) in the
system can be generated from reactions among the components. In a properly
chosen set, no components can be formed from a reaction among the other
components.
Chemical equilibrium problems are formulated in MINTEQA1 by combining
all the mass action constraints (equilibrium constant expressions) for re-
actions among the components with mass balance expressions for each component.
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The number of degrees of freedom of the system is the number of independent
variables. These would ordinarily include temperature, pressure, and all the
component masses that can be independently varied. Several constraints are
used in MINTEQA1 that modify the usual phase rule relationship. Because
temperature and pressure are both specified invariant by the user (pressure
is fixed indirectly by specifying the value of the equilibrium constant appro-
priate for the partial pressure of the gas phase) the phase rule expression
that applies to MINTEQA1 calculations is
f = C - P 4.3
Where:
f = the number of degrees of freedom
C = the number of components
P = the number of phases
One additional degree of freedom is lost for each component entered at
fixed activity (Type 3 species). In MINTEQA1, the activity of the H20 com-
ponent is always fixed at the outset by convention (see Equation 4.34). This
simplification saves computation time and does not significantly alter the
outcome of calculations performed on relatively low ionic strength solutions.
Other components such as pH (H+) and pe (e~) are also commonly fixed at
various activities selected by the user. In addition to these constraints,
MINTEQA1 takes advantage of the phase rule by eliminating one degree of
freedom (fixing the concentration of one component) for each solid phase at
equilibrium with the solution. This follows from the solubility product
constraint imposed by the presence of a solid phase. Consider, for example,
the following reaction
2Ag+ + S2~ <==> Ag2S 4- 4.4
If a pure acanthite phase is present at unit activity,
Kqn = [Ag+]2 [S2~] = ID"56 4.5
&F
and [Ag+] and [S2~] are no longer independent variables.
In the absence of constraints like this, a system containing j compo-
nents would be represented by a set of j mass action expressions of the form
a
C. = Kj TT Xj *J 4.6
Where:
Cj = concentration of species i
Kj = formation constant for species i
10
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X^ = concentration of component j
a-ji = stoichiometric coefficient of component j in species i
IT = indicates the product over all components in species i
One expression of this form will exist for each species i. Activity coeffi-
cients are omitted in Equation 4.6 for simplicity.
In logarithmic form, Equation 4.6 becomes
log Ci = log Kj + I aij log Xj 4.7
j
and in matrix form, the system of equations for all species i can be written
log "C = log K + A log "X 4.8
Where:
log C = a column vector of log Cj
log K = a column vector of log Kj
1og X = a column vector of log Xj
A = the matrix of stoichiometric coefficients aj4
In addition to the mass action expressions, the unrestricted system of j
components would be governed by j mass balance equations of the form
Ti = I aii ci 4-9
i
Where:
T.J = total system mass of component j
Cj = concentration of each species i
ajj = stoichiometric coefficient of component j in species i
Because MINTEQA1 employs an iterative numerical technique (Newton-
Raphson method; see Appendix A) to arrive at the solution, an error term (y-j)
is defined such that
Yj = I atj q - Tj 4.10
11
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Where.
YJ = the error, or remainder, in the mass balance equation
for each component j
A final solution will be obtained when
| y-j | <_ convergence criteria 4.11
The convergence criteria for MINTEQA1 is pre-set to 0.001.
The goal to find a solution such that yj converges toward zero. This
could be accomplished using a variety of available numeric methods. The
Newton-Raphson method is used in MINTEQA1 because it converges rapidly (second
order) near the solution. The drawback is that this method sometimes does
not converge at all if poor initial estimates of component activities (acti-
vity guesses) are provided. The initial activity guesses supplied automati-
cally by PRODEFA1 are set at 1.0 times the total analytical input concentra-
tion of each component. If these prove inadequate, users may provide their
own guesses. It is sometimes helpful to also select the optional line-search
convergence method that is provided in the program. In most cases, conver-
gence will be obtained for properly formulated problems; however, additional
suggestions regarding persistent convergence problems are provided as on-line
text entries in PRODEFA1.
To illustrate the generalized mathematical formalisms useful for solving
chemical equilibrium problems, it is instructive to consider a simple problem
in detail. The example problem formulation that follows is based on a sim-
ple calcium carbonate (CaC03) solution. This solution has served as the
classical example for many chemical equilibrium models and has been discussed
in great detail elsewhere (6, 7, 19). The development that follows is taken
largely from these sources and differs only in the specifics relating to
MINTEQA1. A 0.001 molar solution of CaCC>3 that has no access to atmospheric
gases is considered. Because the CaC03 will dissolve completely in this
case, no solid phases are considered. Furthermore, no sorbent phases are
present, no redox reactions occur, and no "fixed" species are included.
The CaC03 solution at equilibrium will contain nine solution species:
Ca2+, CaOH+, CaC03 (aq), CaHC03+, H2C03, HCO^, Co|~, H+ and OH~. The
first step in formulating the equilibrium problem is to select a minimum set
of "component" species (Type 1 species in MINTEQA1) that will serve as the
sole reactants in the set of reactions that yield all the remaining species
as products. The "complexes" formed by these reactions are defined as Type 2
species in MINTEQA1. Components are selected such that all the required
complexes are formed from reactions among the components. The choice of
components to represent a given solution, in general, is not unique; however,
the component set used in MINTEQA1 is pre-set (see Table 4.1).
The three components from Table 4.1 that are applicable to the CaC03
solution are Ca , C0o~, and H . Water is also a component, but it is
12
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treated somewhat differently than the others in that H20 is presumed to exist
at constant activity. This is a good assumption for all dilute solutions
because the mass of H20 present is several orders of magnitude greater than
the other components. The small mass of water consumed (or generated) by
reactions with other components is justifiably neglected. MINTEQA1 automati-
cally inserts H20 as a component in all solutions and includes the corre-
sponding activity coefficients in all the mass action expressions. Material
balance equations for H20 are not considered because of the constant activity
assumption.
Table 4.2 lists all the species to be considered in the CaC03 problem.
Components (Type 1 species) and their reaction products (Type 2 species) are
listed separately to emphasize the important distinction between species
types.
The set of reactions that generate Type 2 species from the input com-
ponents are tabulated in Table 4.3 and the corresponding stoichiometric
matrix is presented in Table 4.4.
TABLE 4.2. SPECIES TYPES INVOLVED IN A 0.001 MOLAR CaCO^ SOLUTION
All Species Components Complex Species
Present _ (Type 1 species) _ (Type 2 species)
Ca2+
CaOH+
CaHC03+ CaHC03+
CaC03 (aq) CaC03 (aq)
H2C03 H2C03
HC03~ HC03"
o_ o_
co3 co^
H+ H+
OH~ OH~
(H20)* (H20)*
*MINTEQA1 always inserts H20 as an input component having constant activity.
13
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TABLE 4.3. REACTIONS AMONG COMPONENTS TO FORM COMPLEX SPECIES IN A
0.001 MOLAR CaC03 SOLUTION
Reactions log K
(1) Ca2+ --- > Ca2+ 0.0*
(2) Ca2+ + H0 - H+ --- > CaOH+ -12.2
(3) Ca2+ + CO2}" -l- H+ --- > CaHC03+ 11.6
(4) Ca2+ + CO|~ --- > CaC03 (aq) 3.0
(5) C0~ + 2H+ --- > HC0 16.5
(6) CO|~ + H+ --- > HC03 10.2
(7) C0^~ --- > C0^~ 0.0*
(8) H+ --- > H+ 0U0*
(9) H20 - H+ --- > OH~ -14.0
(10) H20 — > H20 0.0*
*These trivial reactions are included only to keep the development in
general form.
14
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TABLE 4.4. STOICHIOMETRIC MATRIX REPRESENTING THE 0.001 MOLAR CaC03 PROBLEM
Species
Ca2+
CaOff1"
CaHC03
r* n r* c\i\ i o j*i i
V^dVyWj \Q.\j^j
H2C03
HCO.T
j
C03~
H+
OHT
H20
Ca2+
1
1
1
1
0
0
0
0
0
0
co3
0
0
1
1
1
1
1
0
0
0
Components
H+*
0
-1
1
0
2
1
0
1
-1
0
H20
0
1
0
0
0
0
0
0
1
1
*Coefficients in the H component column are rationalized using ^0 as the
reference. The CaOH species contains one less H than water; the H2C03
species has two dissociatable H+ ions; the OH~ species has one less H+ than
water, etc. Similar results could be obtained from charge balance
considerations. For example, the reaction in MINTEQA1 for CaOff1" is
Ca2+ + H20 - H+ <====> CaOH+
Thus, the stoichiometric matrix element corresponding to the amount of
H+ in CaOH+ is -1. Similarly for H2C03
C032~ + 2H+ <====> H2C03
Thus, the stoichiometric matrix element for the H in H2C03 is +2.
If MINTEQAl's component list had been arranged differently (we have already
observed that the component list is not unique) so that 0~2 were a component,
then the reaction for ^003 in the database might have been:
C032~ + H20 - 0~2 <====> H2C03
and the stoichiometric matrix element for H involved in H2C03 would be zero.
15
-------
The set of mass action constraints that apply to the reactions in Table
4.3 are given in Table 4.5. In addition to these, three material balance
expressions are required to complete the set of equations that define the
CaC03 system. The material balance expressions are generated by summing the
concentrations of all species involving each of the components and equating
the resulting sums to the respective analytical input concentrations. The
resulting expressions are:
TCa2+ = (Ca2+) + (CaOH+) + (CaHC03+) + (CaC03 (aq)) = 0.001 molar 4.12
TC03~ = (CaHC03+) + (CaC03 (aq)) + (H2C03) + (HC03~) + (CO2,') = 0.001 molar
4.13
TH+ = -(CaOH+) + (CaHC03+) + 2(H2C03) + (HC03~) + (H+) - (OH~) = 0.0 4.14
Where parentheses "( )" denote analytical concentrations.
TABLE 4.5. MASS ACTION EXPRESSIONS APPLICABLE TO THE CaC03 SOLUTION
EQUILIBRIUM*
(1) [Ca2+] Kj = [Ca2+] Kj = 1
(2) [Ca2+] [H+r1 K2 = [CaOH+] K2 = 10~12'6
(3) [Ca2+] [C02~] [H+] [H20] K3 = [CaHC03+] K3 = 1011'3
(4) [Ca2+] [C02~] K4 = [CaC03 (aq)] K4 = 103'2
(5) [CO2,"] [H+]2 K5 = [H2C03] K5 = 1016'5
(6) [C02~] [H+] K6 = [HC03~] K6 = 1010'3
(7) [C0^~] K? = [C0§~] K7 = 1
(8) [H+] Kg = [H+] Kg = 1
(9) [H20] [H+r1 K9 = [OH"] K9 = 10~14'°
(10) [H20] K10 = [H20] K10 = 1
*Brackets "[ ]" denote activities.
16
-------
The ultimate goal is to solve these material balance expressions under
the constraints of the mass action equations in Table 4.5. To do this, the
concentration terms in Equation 4.12 through 4.14 must first be re-expressed
in terms of activities. Solution of the resulting mass balance equations
would yield the equilibrium solution activities of each component species.
The component activities would then be used to calculate the equilibrium
solution activities of each Type 2 species using the mass action expressions
in Table 4.5.
Each concentration term appearing in Equations 4.12 through 4.14 can be
expressed in terms of the corresponding species activity by incorporating the
appropriate activity coefficients (y). For the four input components the
conversions are:
(Ca2+) =
[Ca2+]
YC 2 +
4.15
(CO2,') =
[CO2']
2-
CO,
4.16
(H+) =
[H+]
4.17
(H20) =
[H20]
4.18
Where the parentheses "( )" denote concentrations and the brackets "[ J"
denote activities.
For the remaining six derived species, the mass action expressions also
are incorporated and the resulting expressions are:
K2 [Ca2+] [H20]
[H+]
4.19
(CaHC03+) =
K, [Ca2+]
YCaHCO,
4.20
17
-------
K4 [Ca2+] [CO2"]
(CaC03) = ------------------ 4.21
Kg [H+]2 [CO2-]
(H2C03) = ----------------- 4.22
YH2C03
K6 [H+] [CO2']
(HC03 ) = ---------------- 4.23
~
K9 [H20]
(OH") = ---------- 4.24
The material balance equations that MINTEQA1 will solve result from
substituting these expressions for the concentration terras in Equations 4.12
through 4.14. The final set of material balance equations then becomes:
[Ca2+] K9 [Ca2+] [H70] K, [Ca2+] [H+] [CO2,"]
TCa2+ = _ f ._£ i f __1 ±
[H+] YCaHC03+
Tco3 =
+ ----------------- = 0.001 4.25
YCaC03
[Ca2+] [H+] (CO2'] K4 [Ca2+] [C02~] K5 [H+]2 [CO2-]
+ -------- = o.OOl 4.26
YC03~
-K7 [H90] [Ca2+] Ko [Ca2+] [H+] [CO?"] 2K. [H+]
T, £ Z, _) J J
+ - ----------------- f ----------------------- f
[CO?"] [H+] K9 [H20]
18
= o.OOO 4.27
-------
Equations 4.25 through 4.27 now contain only equilibrium constants,
activity coefficients, component activity terms, and analytical input concen-
trations. The analytical input concentrations ( Ca , C0n~, and H+) are
supplied by the user when the problem is specified. A solution is desired
for the equilibrium component activities, from which the activities of all
derived species can he calculated using the mass action expressions in Table
4.5. A material balance equation for the informal component H20 is not
included. The mass of water present is always several orders of magnitude
greater than the other components and the mass lost due to reactions is
insignificant. Inclusion of the material balance equation would be super-
fluous.
Adjustments to Equilibrium Constants
The equilibrium constants in Equations 4.25 through 4.27 are functions
of the system temperature, but the values supplied in MINTEQAl's thermodynamic
database are referenced to 25°C and an ionic strength of zero. If the tem-
perature is not at 25°C, a new set of equilibrium constants must be calculated
before solving the equations. Also, the activity coefficients are functions
of ionic strength and must be adjusted each time species activities are
varied during the Newton-Raphson iterations.
Equilibrium Constant Temperature Corrections
MINTEQA1 incorporates two schemes for adjusting the equilibrium constants
for temperature. If the necessary data are available in the thermodynamic
database, MINTEQA1 uses a power function of the form
log KT = A + BT + C/T + D Log(T) + ET2 + F/T2 + GT1/2 4.28
Where:
T = temperature (K°), and
A - G = empirical constants stored in the thermodynamic database
Only 25 of the 982 species in the database have these constants available.
For any species that does not have the constants needed for equation 4.28,
the equilibrium constant associated with that species in the thermodynamic
database is corrected for temperature variations from 25°C by the Van't Hoff
equation
AHr 1 1
log KT = log KT ( ) 4.29
r 2.303 R T T_
-------
Where:
Tr = the reference temperature, 298.16°K
log Kf = logarithm of the equilibrium constant at the reference tem-
r perature
R = the gas constant
T = the desired system temperature, °K
o
AH = standard enthalpy change at the reference temperature
Caution should be used in attempting to apply MINTEQA1 to high tempera-
ture systems. The Van't Hoff equation implicitly assumes the enthalpies of
reaction to be independent of temperature. This assumption is not strictly
true and significant errors can result at temperatures far above 25°C. For
this reason, MINTEQA1 calculations should be restricted to a temperature
range below 100°C and applications to high temperature geothermal systems
should definitely not be attempted unless empirical temperature correction
data are available.
If the standard enthalpy change is not available in the database,
MINTEQA1 uses the uncorrected log K's (25°C). Users are encouraged to become
familiar with the database and to evaluate the impacts of these limitations
on their systems. Missing enthalpy data can be permanently added to the
database or, alternatively, temporarily entered into a given model execution
using instructions provided by PRODEFA1. The latter option is convenient for
testing a given system's sensitivity for individual reaction enthalpies.
Activity Coefficient Corrections
Activity coefficients for all species are functions of solution ionic
strength (I) and vary as species distributions alter the ionic strength.
During the iterative solution, successive sets of activity coefficients are
calculated for all solution species. These are used to generate corrected
values of the equilibrium constants that appear in the material balance
expressions being solved. During successive MINTEQA1 iterations, activity
coefficients are calculated in the subroutine ACTVTY and the corrected equi-
librium constants are generated in the subroutine KCORR.
Initial estimates (activity guesses) of the input component activities
are provided in the input file for a given problem. Users may enter their
own values or default to the preset values provided in MINTEQA1. As a de-
fault, the initial activity guesses for each component are equal to the
respective analytical input concentrations divided by 100. Users should be
aware, however, that PRODEFA1 will automatically insert activity guesses
equal to the analytical input concentrations. The MINTEQA1 default is over-
riden for input files developed by PRODEFA1.
20
-------
These initial component activity guesses are used to "crudely" estimate
the concentrations of each complex species so that the solution ionic strength
can be calculated. The solution ionic strength is then used in either the
extended Debye-Huckel equation (17) or the Davies equation (3) to calculate
activity coefficients (y) for all charged species. This latter process is
repeated for each successive iteration step. Successive sets of Y's are
used to derive new log K's from
New log K = Old log K - log Y.
The Debye-Huckel expression used to calculate the activity coefficients
is
-Ad Z2 ,
log Yj = t bj I 4.30
1 + Bd a± I1/2
Where:
A(j and Bj = constants that depend on the dielectric constant
and temperature
Zj = the charge on each species i
aj = ion size parameter
bj = ion specific parameter that accounts for the decrease
in solvent concentration in concentrated solutions
I = solution ionic strength
The ionic strength (I) is calculated from
1 n
I = I Z? C,. 4.31
2 1 = 1
Where:
Cj = concentration of ion species i
n = number of ion species present in the solution
Z-[ = charge on species i
The Debye-Huckel relation above is used only when the parameters aj and
bj are available in the database. The current database contains aj and b|
parameters for many major inorganic ion species and a few important trace
metals. The values used were taken largely from the WATEQ3 data compilation
(1). Where data are not available, MINTEQA1 uses the Davies equation
21
-------
log
AZj2 (
1+11/2
- 0.31)
4.32
in which the variables are defined as in Equation 4.30.
With the exception of H20, activity coefficients of neutral species are
calculated using the development of Helgeson (9),
log
4.33
where the constant cq is set equal to 0.1 in MINTEQA1.
Users are cautioned that the activity correction models presented here
are not intended for use at ionic strengths greater than 0.5. At higher
ionic strengths, users should consider adding expanded versions of the Debye-
Huckel equation, which include terms to account for ion interactions occuring
in more concentrated solutions. The work of Pitzer and coworkers (14-16)
provides some useful alternative equations.
The activity of water is estimated from
[H20] = 1 - 0.017
1 = 1
Ci
4.34
where the Cj's represent the concentrations of individual ion species.
Equation 4.34 is applicable only in dilute solutions and is based on a deri-
vation using Raoults' law. The proportionality constant (0.017) is derived
from a plot of H20 activity versus the number of solute ions (8).
Successive sets of log K values that reflect the temperature corrections
(Van't Hoff) and activity coefficient corrections (Debye-Huckel or Davies)
above are computed in subroutine KCORR and substituted into the mass balance
expressions. If no solids are specified, the Jacobian matrix relating changes
in mass balance to changes in component activities is used to calculate that
set of component activities that will simultaneously minimize the mass imbal-
ance for all species. The procedure used is iterative Gaussian elimination
and back substitution with a convergence test following each iteration.
In systems containing solids, the material balance equations are further
altered before the new set of activities are determined. Assume, for instance,
that the example CaC03 system described earlier was placed in contact with a
very large excess of CaC03 solid phase. This situation might arise if the
carbonate solution was flowing through a fractured limestone aquifer matrix
material. This new system would be modeled by including a fixed solid phase
22
-------
(Type 3 species) of calcite. The calcite solubility product constraint would
then be imposed and one degree of freedom would be lost. Stated differently,
the free carbonate ion activity would no longer be an independent variable
because of the following reaction and corresponding Ksp relationship.
Ca2+ + CO|~ --- > CaC03 4- 4.35
(calcite)
[Ca2+] [C02~] = constant = Ksp (calcite) 4.36
The free carbonate ion activity would be expressed as
[CO2"] = -------------- 4.37
Ksp [Ca2+]
and eliminated from the mass balance expressions (Equations 4.25 through
4.27) by substitution. After doing this, the new mass balance equations
would become
[Ca2+] K7 [Ca2+] [H90] K, [Ca2+] [H+]
TCa2+ = -------- + __2 ---------- 1 --- + ---- £ ----------------
Ksp [Ca2+]
K4
+ ------------ = o.OOl 4.38
Ksp
K K [Hf]2
4
YCaHC03+ Ksp YCaC03 Ksp YH2C03 Ksp [Ca2+]
"CO^ = + +
K6
Ksp [Ca2+] YCo| Ksp [Ca2+]
0.001 4.39
-K2 [H20] [Ca2+] K [H+] 2K [H+] 2
TH+ = ----------------- 4-
YCaOH+ [H+] YCaHC03+ K ^H2C03 Ksp [Ca2+]
K6 [H+] [H+] K9 [H20]
+ ------------------- + ---------------- = 0.00 4.40
Ksp [Ca2+] ^H+
23
-------
Note that Equations 4.38 through 4.40 now contain only [Ca^+] and [H+]
terms as unknowns. Carbonate ion activity has been eliminated as a component
and the dimensions of the Jacobian matrix to be calculated during the Newton-
Raphson iteration sequence have been reduced. For more complicated systems
that may contain a number of solids (Type 3, 4, 5), the process of eliminat-
ing variables is more complicated. A priority order of thermodynamic stabi-
lities of each solid is established by comparing the appropriate ion activity
products (IAP) existing during each iteration step with the corresponding
solubility products. The logarithmic ratio of these terms (saturation index)
is calculated in the solubility submodel and used to establish the stability
order for precipitation or dissolution of solids.
IAP
Saturation Index = log ( ) 4.41
Ksp
If the saturation index for a particular mineral is negative, the system
is undersaturated with respect to that mineral. If the index is positive,
the solution is supersaturated and MINTEQA1 will precipitate the solid in
question until the equilibrium condition is satisfied, i.e., until:
IAP
log ( ) =0 4.42
Ksp
Undersaturation for a given mineral can arise from three situations: a) a
less soluble mineral phase could be controling the activities of one or more
common ions, b) the component input concentrations are insufficient to exceed
the solubility product, or c) free solution ion activities are limited by
sorption reactions.
The MINTEQA1 program re-evaluates the saturation indices for each solid
during each iteration step using the activity coefficient and log K correc-
tions noted earlier. During the iteration sequence various solid phases may
precipitate or redissolve as dictated by the saturation index. Because the
formation of solid phases changes the equilibrium species distributions, the
inclusion of a large number of Type 4 or 5 solids in MINTEQA1 executions
requires that the species distribution equilibria problem be re-solved
several times during the iteration sequence for precipitating solids. The
difficulty of obtaining convergence is increased accordingly. For this
reason, model systems should be spared unnecessary detail. Users should note
that normally only one, or sometimes two or three solids control the free
solution activities of species representing a given metal. Users working
with a given system can benefit from results of pilot model runs to refine
their solids lists. The initial rule is, "if in doubt leave it out." The
saturation index listings can be used to detect first-pass mistakes. All
unprecipitated (supersaturated) solids will be represented by a positive (>0)
saturation index. If any positive values are found, the user may then add
24
-------
the omitted solid and repeat the execution. It also would be prudent to
eliminate any solids initially included, but which did not precipitate (i.e.,
sat. index <0). In the final analysis, all controlling solids (those that
actually precipitate) will be identified with saturation indices equal to
zero. Others need not have been included and execution time would have been
reduced had they been left out.
Imposition of a fixed gas phase on the example CaC(>3 system would have
much the same effect mathematically as adding a Type 3 calcite phase. When
a carbon dioxide (CC^) gas phase is present, the following reaction would
apply.
+ 2H+ <===> C02(g) + H20 4.43
The corresponding mass action expression would be represented by
[PC02] [H20]
-------------- = K ; log K = 18.16 4.44
[C0§-] [H+]
where [ €02] = the partial pressure of COo and the other terms are the
respective species activities. For systems open to the atmosphere, CC^ is
fixed at about lO"-**-1 atmospheres. PRODEFA1 accommodates this constraint by
incorporating the fixed partial pressure term into the equilibrium constant
for Equation 4.44. If PRODEFA1 is not used to assemble the input file, the
user is expected to calculate the log K of the gas at the chosen partial
pressure and enter it manually into the input file. In this case, log [002]
= -3.5, the initial log K = 18.16 and the new log K' becomes
log K1 = 18.16 - (-3.5) = 21.66 4.45
Users should note that it is possible to overconstrain a system (elimi-
nate all degrees of freedom) by entering too many fixed species. If, for
instance, a user simultaneously fixed [ 002] and the pH and entered carbonate
as a component, there would be no remaining variables in Equation 4.44 and
the system would be overconstrained. In this case, MINTEQA1 would eliminate
carbonate as a component and remove the carbonate mass balance expression.
In so doing, the carbonate ion activity is calculated from the fixed pH and
dissolved CO? levels.
In introducing the CaC03 problem originally, the gas phase reactions
were purposefully excluded. If this problem had been executed using MINTEQA1,
the user would have been reminded of this exclusion in the output listing for
Type 6 (excluded) species. Other Type 6 species include components that do
not have corresponding mass balance equations. Examples are the electron
(e~) and the adsorption potentials used as components in defining sorption
equilibria in the constant capacitance and triple-layer sorption models.
25
-------
Sorption algorithms
Six options are available In MINTEQA1 for modeling sorption processes.
These Include: 1) the activity K^ model, 2) the activity Langmuir model, 3)
the activity Freundlich model, 4) the ion exchange model, 5) the constant
capacitance model, and 6) the triple-layer model. Thermodynamic data for the
sorption models are not included in the MINTEQA1 database. Use of any of the
sorption models, therefore, requires that users have their own data sets
available. Mathematical formalisms, input data requirements, and formatting
details of the individual sorption models are discussed in the separate sec-
tions below.
Activity K^ sorption model
The activity K^ sorption model is similar in some respects to the simple
partition coefficient concept of sorption in which the partition coefficient
is defined as the ratio of sorbate ion concentrations in the sorbed phase
relative to its concentration in the equilibrium sorbate solution. That is,
if we represent the sorption reaction as
SOH + M <===> SOHM 4.46
where SOH represents an unoccupied sorbent site and M is a dissolved sorbate
ion, then the conventional partition coefficient (Kp) would be defined by
(SOHM)
K = — 4.47
(M)
Where:
(SOHM) = concentration of the sorbed complex
(M) = concentration of M in the equilibrium solution
The MINTEQA1 activity K^ concept differs from this conventional repre-
sentation in two important aspects. Because the unknowns in a MINTEQA1
problem are the free solution activities (as opposed to analytical concentra-
tions) of the components, the conventional partition coefficient in Equation
4.47 must be redefined in terms of species activities. Also, because the
conventional partition coefficient expression does not account for the total
mass (or concentration) of unreacted sorbent sites (SOH) initially available,
the sorbent is presumed to exist at constant activity equal to 1.0. The mass
action expression for reaction 4.46 then becomes
[SOHM]
Kact = 4>48
d [M]
26
-------
[SOHM2]/[SOHMj] is fixed. This is equivalent to assuming that the mass of
sorbent SOHMj initially available is infinitely large such that [SOHM^] does
not change significantly when M,+ ions are expelled to solution even though a
substantial increase in [Mj"1"] results. With the ratio [SOHM2J/ [SOHMj] fixed,
a new exchange constant Kex can be defined such that
+ 1
[SOHMj] [Mj"1"]
Kl — V —- — _-.____ /, R 7
PX "" GX — ^~™~—— — ^. J /
[SOHM2] [M2+]
Selectivity coefficients (KpX's) can be derived from the literature for
most common ions such as Na , K+, Ca^"1", Mg2+, etc. , but are seldom available
for trace metals. In using the ion exchange algorithm, users must supply the
reaction stoichiometries and selectivity constants and specify that sites
were initially saturated with the chosen native ion. Note also that reaction
stoichiometries must change relative to the example given if multivalent
species are sorbed.
Constant Capacitance and Triple-Layer Sorption Algorithms
All four sorption models discussed thus far neglect the electrostatic
influences of charged sorbent surfaces on the nearby solution and the counter
influences of changes in sorbent surface charge due to solution composition.
Many colloidal sorbents carry significant surface charges that create elec-
trostatic potentials extending into the suspending solutions. Solution ions
of like charge are repelled exponentially and ions of opposite charge are
attracted. Because of this, the electrostatic potentials associated with
charged sorbents strongly influence the sorptive behavior of charged species.
This effect results from the fact that the activities of sorbate ions ap-
proaching charged surfaces are modified by the electrical work necessary to
penetrate the zone of electrostatic potentials (^'s) extending away from
the surface.
Several models are available to account for these effects in various
degrees of detail. Readers are refered to Westall and Hohl's (20) excellent
review for clear comparisons of the presently available surface complexation/
electrostatic models. The discussion that follows will be limited to brief
descriptions of the two surface complexation model options provided in
MINTEQA1; the constant capacitance model and the triple layer model. These
two models are closely related in many ways. Each treats the sorption pro-
cess as a surface complexation reaction and accounts for the electrostatic
potentials extending from the charged sorbent surface. They differ primarily
in the types of surface species considered and the theoretical constructs
used to develop the mathematical formalisms relating surface charge (a) to
electrostatic potentials (ifj) near surface planes and in the diffuse ion
layer.
31
-------
Most of the surface coraplexation models available were developed to
describe sorption reactions In crystalline oxide systems (4). They also have
been applied with reasonable success to pure amorphous iron oxyhydroxide
systems (2, 5) and more recently to clay systems (11). The large body of
experimental evidence that has accumulated from laboratory bench studies of
pure oxide systems indicates that surface complexation models can predict
adsorption behavior. Unfortunately, few data exist for applying these models
to natural systems where complex mixtures of impure amorphous oxides, clays,
and hum! c materials make up the sorbent matrix. Freshly prepared laboratory
oxide systems often behave differently from the aged, impure mixtures found in
the environment. The interactions are such that properties of the mixture as
a whole are not necessarily those obtained by summing the properties of the
individual components. Care must be used in selecting input parameters
for MINTEQAl's surface complexation model algorithms in natural systems.
The constant capacitance and triple layer models both treat trace metal
sorption reactions as complexation reactions analogous to the formation of
complexes in solution. Surface sites are represented as SOH groups where S's
are metals associated with the solid structure and located at the solid-
liquid interface. Some ions, such as H+, OH~, and a variety of trace metal
ions are presumed to be specifically adsorbed at the surface via complexation
with the surface sites. With the constant capacitance model, all specifically
adsorbed ions contribute to the surface charge (a). However, in the triple
layer model, only H+ and OH~ are "potential-determining" ions. (Trace metals
are presumed to reside in the Tb' plane.) Because the electrical potentials
gradients extending away from the surface are the direct result of the sur-
face charge, the specifically adsorbed potential determining ions also govern
distributions of counter ions in the diffuse layer zone. Common solution
I I 91 _ 0_ J
ions such as Na , K , Ca , Cl , SOf etc. are not strong complexers and are
usually not strong contributors to the surface charge. Also, because trace
metals are usually present at relatively low solution activities, the species
H+ and OH~ are usually the dominant contributors.
Activities of ions near the surface are influenced by the presence of
electrostatic potentials arising from of the surface charge. The activity
difference is the result of electrical work that must be performed in moving
sorbate ions across the potential gradient between the charged surface and
the bulk solution. The activity change between these zones is related to the
ion charge (z) and the electrical potential (40 near the surface and can be
expressed using the exponential Boltzmann expression,
Where:
[Mcz] = [M z] e-zFR 4.58
S 3CJ
[M z] = activity of a metal M of charge z near the surface
S
[M z] = corresponding activity of M in bulk solution
outside the influence of the charged surface
32
-------
= Boltzmann factor
F = Faraday constant
R = ideal gas constant
T = absolute temperature
The Boltzmann factor is associated with an additional MINTEQA1 electrostatic
potential input component (designated XPSIO) and appears in the mass action
expressions representing surface complexation reactions as an activity coeffi-
cient correction. Since there is no analytical input of total surface charge
1(0"), these electrostatic components are unique. The total charge must be
calculated from the mathematical formalisms relating surface charge to electro-
static potentials.
a = f(i|;) 4.59
and
T(o) = f(ij>) (constant)
Where the constant accommodates a unit conversion from coulombs of charge per
square meter to moles of charge per liter. The constant capacitance and
triple layer models use different mathematical formalisms (f(t)'s) to relate a
and ip. In both cases, the mass balance relationship used to check convergence
of each electrostatic component is
n
Y(a) = I [a(i, a) Cj] - T(o) 4.60
i
Where:
Y(a) = the difference function, which converges to zero as the
final solution is approached
a(i, a) = the stoichiometric coefficients of the electrostatic
component to species i
Cj = concentration of species i
n = number of species involved
33
-------
Other details specific to the constant capacitance or triple layer models are
discussed in separate sections below.
a) Constant Capacitance Model
In the constant capacitance model, all specifically adsorbed ions are
considered potential determining species and are located in the surface ('0')
plane (Figure 4.1). The double layer capacitance (C&) is taken to be
constant and the surface charge (ao) and electrostatic potential are related
by
tfn ~
4.61
Where:
the surface potential
CONSTANT CAPACITANCE MODEL
SURFACE
SPECIES
CHARGE-
POTENTL4L
RELATION-
SHIPS
S -
s -
s -
2 _,
S -
s -
s -
^*
"^p~
J <\i/
^ Yo
f—
E-
o
CX,
- 0
- 0
- 0
- 0
- 0
- 0
- 0
v
— H
. /
— H
— H
— M
\
M
/
/~T
0
r
3
o
3
^-
rl
C
"X ^
N^
^v
\
< ^*z 1
"^ Kttl itASS ACTION CONSTANTS
CORRESPONDING TO
^ KM, THE INDICATED
SURFACE REACTIONS
< KM2
'H' PT AMP AT PnTPMTTAT -if-
U rLAiNL Al rUlLMliAL T^
AKD CHARGE CTO
f^" ij' py AMP HH niTTPP/
HELMHOLTZ PLANE.
Y{ )
-*^f" _ rvirr'T Tor> rrt\r T i \rr>r» *-^^
DISTANCE FROM SURFACE (X)
Figure 4.1. Schematic representation of the surface charge/potential
relationships used in the Constant Capacitance Sorption
model. Surface species indicated correspond to reactions
4.62, 4.66, 4.68 and 4.69 and mass action expressions for
Kal > Ka2 > KM1» ancl KM2 ln Equations 4.63, 4.67, 4.70 and
4.71 as discussed in the text.
34
-------
Surface sites are represented by the component SOH (ID number 990), which is
treated as a conventional ligand group.
Sorption processes are written as reactions between components to form
complexes and are represented by conventional mass action expressions with
one key exception. The electrostatic interaction between the charged sorbate
ions and the charged sorbent surface requires that electrical work be per-
formed in moving the sorbate ion from bulk solution to the surface 'o1 plane.
Said differently, the activity coefficients of ions near the surface are
different from those of the same ion in bulk solution due to the electrostatic
potential originating at the surface. To accommodate this effect, the mass
action expressions incorporate the Boltzmann factors discussed earlier as
activity corrections. Ion charge and reaction stoichiometries must be used
in incorporating the Boltzmann factors. A few surface complexation reactions
and the corresponding mass action expressions are given below to illustrate
the use of Boltzman factors. Consider the protonation reaction
Ka
_ al
SOH + H+ <===>
S
SOH
4.62
where H denotes a hydronium ion near the surface.
action expression would be
[SOHj]
The corresponding mass
[SOH] [H+]
where brackets "[ ]" denote activities.
In MINTEQAl's constant capacitance model, the surface species are pre-
sumed to have activity coefficients equal to unity and the terms [SOH«] and
[SOH] need no further conversion; however, the activity of the surface hydro-
nium ions must be corrected for the energy expended in moving them to the
surface where the final complex formed. This is accomplished by expressing
[H ] in terms of the bulk solution hydronium ion activity [H+] (i.e., in
terms of the original Type 1 component species for which MINTEQA1 will find a
solution). In this case the Boltzmann equation is written
4'64
where [H+] is the bulk solution hydronium ion activity and z = 1.
The mass action expression used in MINTEQA1 is obtained by substituting
this expression into Equation 4.63.
[SOHj]
+ i
[SOH] [Haq] e
[SOH
[SOH] [Haq+]
35
-------
For the corresponding deprotonation reaction
Ka
_ a2 _
SOH <===> SO + H+ 4.66
the surface hydronium ion activity term [H*] appears as a product and the
Boltzmann factor enters into the numerator of the mass balance expression.
[SOH] [SOH]
Reactions 4.62 and 4.66 involved transport of only one monovalent species
(H+) across the potential gradient. For multivalent species, both ion charge
and stoichiometric coefficients must be considered. These formalisms can be
illustrated for reactions of a divalent ion M^+. Consider for instance the
reactions
_ KM! _
SOH + M2+ <===> (S0~ - M2+)+ + H+ 4.68
s s
and
2+ === ~ - 2+° +
(SOH)9 + M <===> ((S0~)9 - M)° + 2H 4.69
z, s *— s
In reaction 4.68 the hydronium ion is expelled to the bulk solution (Boltzmann
factor in numerator) and M^+ is moved across the potential gradient in the
other direction.
The corresponding mass action expression for reaction 4.68 is
[(SO- - M2+)+] [H+]
KM
1 [SOH] [M2+]
9, , , -Fif /RT
[(SO" - M2+)+] [HaQ+] e °
li 4.70
9, -2F* /RT
[SOH] [Maq2+] e °
[SOH] [M
aq
36
-------
O 4- *"* I
where [M_ ] and [M~ ] represent ion activities in the bulk solution and
3 (-J c>
near the sorbent surface, respectively.
Reaction 4.69 will be used to illustrate the formulation where both
multivalent ions (M^+) and stoichiometric coefficients greater than 1 (i.e.,
for H+) occur. The mass action expression for reaction 4.69 is written
s
[((S0~)2 -
t(SOH)2] [M2+]
[((S(T)2 - M^
KSOH)2] [Ma
[((S0~) 2 - M2+
)°] [Haq+]
-2F
] e
)°] [Haq+]
e
/RT
f(SOH)2] [Maq]
Notice that the two's (2's) in the exponents of the Boltzmann factors occurred
for different reasons. The two in the numerator occurred because the [H ]
term was squared (stoichiometry). In the denominator, it occurred because
M^"1" was divalent and z = 2 in Boltzmann exponent -2F,b /RT.
Mass action expressions for all other possible surface complexation
reactions are formulated similarly. The surface site (SOH) is treated as a
Type 1 MINTEQA1 component. Two MINTEQA1 surface site components SOH^ and
SOH2, are used to provide versatility in treating problems that have more
than one kind of sorbent present. The ID numbers are 990 and 991, respec-
tively, and they may be used interchangeably or together.
The mass balance expressions for the surface site components are formu-
lated by summing all the surface species. For the reactions discussed thus
far (4.62, 4.66, 4.68 and 4.69), six surface species were involved and the
mass balance expression for this system would be
TSQH = [SOH] -*- [SO"] + [SOHj] + [(S0~ - M2+)+] + 2[(SO~)2 - M2+)°]
4.72
This expression can be written in terms of surface species activities rather
than concentrations because of the assumption (in MINTEQA1 ) that surface
species have unit activity coefficients. The analytical input concentration
for TSQH must be expressed in moles of sites per liter and is calculated from
37
-------
Ng SA Cg
TSOH = ---------- 4.73
Where:
Ng = the analytically determined surface site density (number of
sites/m2)
f\
S. = specific surface area of the solid (m /g)
Cs = concentration of solid in the suspension (g/£)
NA = Avogadros' number (6.02 X 1023)
Convergence is checked using the difference expression
Y(a ) = £ (all charged species in the 'o1 plane) - oo 4.74
Again, using the reactions 4.62, 4.66, 4.68, and 4. 69 as an example system,
the charged species in the 'o' plane include SOH^, S0~, and (S0~ - M2 ) +
and the total charge is
a0 = £ (charged species in 'o1 plane) = (SOH) - (S0~) +
((SO- - M2+)+) 4.75
Three "electrostatic components" are used in conjunction with the
electrostatic adsorption models in MINTEQA1. They are denoted by XPSIO,
XPSIB and XPSID (component ID numbers 992, 993 and 994) and represent the
electrostatic potentials existing at the surface 'o1 plane, the 'b' plane and
the !d* plane respectively as illustrated in Figures 4.1 and 4.2. Only the
XPSIO component is used with the constant capacitance model. Unlike the
regular components, the electrostatic components have no mass in solution
and are excluded from mass balance calculations by entering them as Type 6
(excluded) species. An activity guess must be entered for XPSIO in the
constant capacitance model. Typical values for log [XPSIO] are from -0.2 to
-4.0. A reasonable initial activity guess is log [XPSIO] = -1.0. The use
of components XPSIB and XPSID in conjunction with the triple layer model are
discussed later under the heading "Triple Layer Model."
The constant capacitance model requires inputs for C^, Ns, S^, and Cs in
addition to expressions for the surface complexation reactions and associated
equilibrium constants (reactions 4.62, 4.66, 4.68 and 4.69 in the examples
used here). These inputs are selected as follows:
38
-------
1) C . This is the 'o* layer capacitance in Farads/m^. It is calcu-
lated from
4.76
where the o~0 and '^0 values used must apply to a system at the
same ionic strength and having the same electrolyte composi-
tion as that used in deriving the mass action constants. A
typical value for the inner layer capacitance would be about
1.4 Farads/m^, but the value used should be based on a know-
ledge of the system to be modeled.
2) Ng: This is the analytically determined surface site density of the
sorbent expressed in number of sites/m^. It is used to calcu-
late the analytical input concentration of the sorption site
component SOH (ID number 990) using the expression
Nc . p
Q A *5
TSOH = 4.77
is entered as the analytical input concentration for
component SOH.
i-\
3) S.: This is the surface area of the sorbent in m /g.
4) Cs: This is the concentration of the sorbent in suspension ex-
pressed in
The adsorption (surface complexation) reactions are entered along with
the appropriate equilibrium constants in the input file. Reactions entered
there should conform to the formats used in example reactions (4.62, 4.66,
4.68, and 4.69) developed earlier. The corresponding equilibrium constants
ai, ao, Mi, and Mo also must be entered. These should not be confused
with the intrinsic constants, commonly found in the literature. All surface
reactions in MINTEQA1 must be written in terms of the neutral surface sites
SOHj and SOH2 (components 990 or 991). Many of the values found in the lit-
erature are intrinsic constants, which are referenced to the protonated
surface site SO!^ (for adsorbing anions) and to the deprotonated site S0~
(for adsorbing cations). Appropriate conversion formulae are summarized in
Table 4.6.
39
-------
TABLE 4.6. RELATIONSHIP BETWEEN MINTEQA1 EQUILIBRIUM CONSTANTS FOR SURFACE
COMPLEXATION REACTIONS AND INTRINSIC CONSTANTS COMMONLY FOUND
IN THE LITERATURE
Constant for use in
MINTEQA1
Intrinsic Constants
1) log K.
anion
log K + log
2) log K
hydrated anion
log K*nt + log
Qf
Where:
K
int =
al
[SOH] [H+]
K
int
[SO ] [H*]
TSOH]
• T nCT iffi
I0g ^hydrated anion
3) log K
cation
K
cation
,int
"a2
4) log K
hydrated cation
log K-'L + log
catlon
+ log
Of
40
-------
b) Triple Layer Model
The triple layer model differs from the constant capacitance model in
several primary ways even though the two models also have much in common.
In the triple layer model, only protonation and deprotonation reactions are
allowed to occur at the surface ( 'o' plane). Other specifically adsorbed ions
are allocated to the 'b' plane (Figure 4.2) and determine the charge o^ and
potential ^ in that zone. Nonspecif ically adsorbed ions are envisioned as
residing in the outer Helmholtz layer or 'd' plane and are influenced by
^d potentials. Basically, one additional capacitance layer has been added
to the formalisms used in the constant capacitance model. Specifically,
adsorbed ions other than H+ or OH~ determine the potentials in the new layer
and background electrolytes are allowed to adsorb.
Most of the inputs for the triple layer model are similar to those for
the constant capacitance model except that the potentials at the 'b1 and 'd'
planes are introduced by the two additional electrostatic conponents XPSIB
(T.D. number 993), and XPSID (I.D. number 994), respectively. Inputs for
adsorbent concentration (g/&), surface area (m^/g) and inner layer capacitance
(farads/m^) are required as in the constant capacitance model. An additional
entry for the outer layer capacitance (€2) also is required. Typical values
for the outer layer capacitance are around 0.2 farads/m^.
As in the constant capacitance model, the electrostatic components have
no mass in solution and are excluded in mass balance calculations. They are
entered as Type 6 excluded species. Log activity guesses for components
XPSIB and XPSID in the range -0.2 to -4.0 are appropriate.
Sorption reactions in the triple-layer model are represented analogously
to the constant capacitance model except that three potential planes are
distinguished that correspond to the 'o' plane, the 'b' plane and the 'd'
plane, respectively. The Boltzmann factor activity correction terras are
specific for the potential zones across which the inner and outer zone ions
must respectively move (Figure 4.2). Stoichiometric coefficients on the
electrostatic terms are positive for reactants and negative for products.
For monovalent electrolytes, the total 'd' plane potential is related to
the total diffuse layer charge (ad) by the Gouy-Chapman relationship.
°d = "(eeo RIT) slnh (*>d/2RT) 4.78
Where:
e = dielectric constant
1O O
e = permittivity in free space (8.85 x 10"1 (coulombs) /joule-m
I = ionic strength
MINTEQA1 also uses Equation 4.78 as an approximation for nonsymmetric
electrolytes.
41
-------
TRIPLE LAYER MODEL
SURFACE
SPECIES
CHARGE/
POTENTIAL
RELATION-
SHIP
S -
s -
S.
s -
s -
s -
s -
s -
s -
t
.
s
F -\h
h Yb
U'. o//
o Yd
^
- 0 —
- 0 —
- n
- 0 — •
- 0 -
- 0 —
- 0 — -
- 0 —
- 0 —
1
1
1
1 1 f
0
;
0
0
11
0
n
n
r
1
1
1
«• 1
j
" — M2f
" — MOU*
u 1 •
- — M4"
z — A"
J — A2'
i -^
C\ r*
1 1 ^-Z
,c r >
\
\1
^\_
J.._T^-,
l
r IT . i
•< K. —
*i
< Ku«
< Kuoa»
-< Ky»
< KA-
< KA.- —
_^.
~~*
\
^\
^ t>ir-t-lirT'
EQU1UDR1UU
CONSTAiiTS
•h' P1JU1F
U 1 LJ\l 1 C«
, «j« pljvNF
u « IWVii O
^^
i Avrn DP Vi
COUNTER 10N3
DISTANCE FROM SURFACE (X)
Figure 4.2. Schematic representation of surface species and charge/potential
relationships in the triple layer sorption model. Nomenclature
is similar to that of Figure 4.1.
42
-------
Surface charges associated with the triple layer model's 'o' , 'b' , and
'd' planes are related to the potential differences between planes.
*0) + C2 (tb - ^d) 4.79
°d = C2 <*d - V
Where:
ao» ab> an^ ad = surface charges associated with the 'o', 'b', and
'd' planes, respectively
GI and C2 = are capacitances associated with the zones between the
'o1 and 'b' planes and 'b' and 'd' planes, respectively
^o ^b» anc* td = electrostatic potentials at the 'o', 'b', and 'd1
planes, respectively
Potential gradients in the inner and outer zones are linear, but potentials
decay exponentially in the diffuse layer zone.
The following reactions and mass action expressions are developed to
illustrate the mathematical formalisms associated with the sorption reactions
depicted schematically in Figure 4.2. The mass action expressions for the
reactions corresponding to equilibrium constants a, and a? in Figure 4.2
are identical to those already presented for the constant capacitance model
(Equations 4.67 and 4.69) and will not be repeated here. The next reaction,
representing the metal ion M2+ in Figure 4.2, can be written
_
SOH + M2+ <===> (S0~ - M2+)+ + H+ 4.81
s s
Where: The subscript 's1 designates ions in the surface zone.
' The mass action expression for Ktf+ is constructed using the Boltzmann
factor e~2FAi(VRT where Ai|> is the potential difference through which the
adsorbed or expelled ions must pass (see Equation 4.58).
KM2+ = --- --- ----------- - e RT 4.82
[SOH] [M 2+]
aq
The combined hydrolysis/sorption reaction for an M2+ ion (designated by
*n Figure 4.2) would be expressed
43
-------
KM
SOH + M^+ + H20 <===S=> (S0~ - MOH+)° + 2H+ 4.83
and the corresponding mass action expression would be written
- b)
[(SO - MOH+)°] [Hpn+]2 -
e KT 4.84
[SOH] [Ma 2+] [H20]
For the monovalent metal ion M+ reaction
K +
SOH + M+ <===> (SO" - M+)° + H+ 4.85
S o
the mass action expression is
_,_ _,_ -F(*o -
[(SO" - M+)°] [H ]
KM+ = — e RT 4.86
[SOH] [Maq+]
For the reaction of a monovalent anion (A~) a neutral surface species
results
K _
SOH + A~ + H+ <===> (SOHt - A~)° 4.87
So ^-
and the mass action expression for K^- is
_
[(SOH2-A-)°] ---- -- ------
K = ---- ---------------- e RT 4.88
[SOH] [Aaq-] [Haq+]
Note that the sign (+) on the Boltzmann factor exponent has reversed because of
the negative charge on A~ and the fact that the hydronium ion term appears in
the denominator.
The final reaction in Figure 4.2 for a divalent anion (A~) can be
represented by
44
-------
V _
SOH + A2~ + H+ <====> (SOHt - A2~) 4.89
The corresponding mass action expression is
2~
[(SORT - A*~)
K 2_ = e 4.9(
A [SOH] [A 2~] [H +]
The two (2) in the Boltzmann exponent arises from the divalent charge on
A2".
As in the constant capacitance model, the mass balance expression for
the surface site component is obtained by summing all the surface species
activities. For a system involving the reactions in Figure 4.2, the mass
balance expression would be
Tcr,H = [SOH] + [SOHt] + [S0~] + [SOH, - A ] + [(S0~ - M1")0]
oUrl /. L
+ [(S0~ - M2+)+] + [(S0~ - MOH+)°] + [(SOIlJ - A
4. 91
Recall that surface site species in the MINTEQA1 formulation have unit
activity coefficients and the activities equal the concentrations.
Charge balance expressions for the electrostatic components representing
each charged surface XPSIO, XPSIB, and XPSID can be written, respectively as
Y(o0) = I (charged species in 'o') - T(cr0) 4.92
Y(ob) = I (charged species in 'b') - T(ob) 4.93
Y(ad) = [(-8ee0RTI)1/2 sinh (F^d/RT) - [C2d|»d - i^) ] 4.94
where we recall that
T(OO) = a0B 4.95
T(ab) = abB 4.96
45
-------
in which Bis defined by
B = 4.97
n
Where S, is the sorbent's specific surface area in m /g, C is the sorbent
concentration in suspension in g/£, and F is the Faraday constant. The
summation terms in Equations 4.92 and 4.93 include all the charged species in
the respective layers and may be written as follows for the system of reac-
tions illustrated in Figure 4.2.
I (charged species in 'o') = [SOH^] + [(SOH^ - A~)°] - [S0~]
- [(SO- - M+)0] - [(SO" - M2+)+]
- [(SO- - M2+)+] - [(SO- - MOH+)o]
+ [(SOH2 - A2~)~] 4.98
I (charged species in 'b') = [(S0~ - M+)°] - [(SOHj - A~)°]
+ 2[(SO~ - M+)+] + [(SO" - MOH+)']
- 2[(SOH+ - A2~)~] 4.99
Notice that the signs ( + , -) on the terms in Equations 4.98 and 4.99
relate to the charge on the part of the complex that resides in the respec-
tive zones. For instance, the overall charge on the complex species (SOl^ -
A~)° in Equation 4.98 is zero, but the part of the complex that resides at
the 'o' plane (SOtlU) has one positive charge, hence the positive ( + ) sign
on term [ (SOH^ - A )°]. The term [(SOH~£ - A~)°] in Equation 4.99 has a
negative (—) sign because the anionic part of the complex is located in the
'b' plane. The positive part (SOHt) does not enter Equation 4.99 because
it resides in the 'o1 plane.
Users are cautioned that the equilibrium constants for mass action
expressions presented here are not the intrinsic constants often reported in
the literature for protonated (SOH.-,) or deprotonated (SO ) surface sites.
All MINTEQA1 reactions are based on the neutral SOH surface site. See Table
4.6 in the discussion concerning the constant capacitance model for appro-
priate conversion formulae.
46
-------
CHAPTER 5
GETTING STARTED
The purpose of this chapter is to inform users how to use PRODEFA1 to
construct input files for MINTEQA1. The quickest way of learning to assemble
input files is to run through the PRODEFA1 interactive session a few times
and note the changes in the resulting files as you change responses to key
questions.
Users should be aggressive in trying new "branches" of the question
sequence by specifying fixed solids, gas phases, redox reactions, and sorp-
tion algorithms. If some of the questions seem unclear, use the on-line help
texts to get further explanations. If a question still seems unclear, just
enter any answer PRODEFA1 will accept and move ahead. Some of the subsequent
questions and comments may eliminate the confusion. Incorrect responses can
be changed later using the editing option provided at the end of the question
sequence.
A sample PRODEFA1 dialogue is provided in Appendix B to illustrate the
sequence of questions involved in defining a simple CaC03 solution speciation
problem. Because of its inherent simplicity, the CaC03 problem dialogue
illustrates only a few of the questioning sequences represented in the pro-
gram. It is provided to give readers of this manual a brief introduction to
PRODEFA1.
After an input file has been assembled using PRODEFA1 and executed
through MINTEQA1, the results may indicate that one or more changes need to
be made in the input file. For example, the user may discover that a compo-
nent was initially entered at the wrong concentration or was omitted alto-
gether, or that the number of iterations specified was inadequate. PRODEFA1
provides the option of specifying an already existing MINTEQA1 input file for
modification. During such sessions, the data from the existing file are
displayed and the user is given the opportunity to change, add, or delete
entries. This feature avoids time consuming duplication of effort in build-
ing MINTEQA1 input files that are substantially alike, as well as in correct-
ing existing files. Note that when PRODEFA1 is used in this manner, the
previously existing file is preserved unchanged. The modifications are
specified and the modified MINTEQA1 input data are written to a new file for
which the user must specify a new file name.
Structure of the MINTEQA1 Input File
A MINTEQA1 input file can consist of four basic kinds of information:
47
-------
1) The problem-specific constants and options;
2) The component species;
3) The other species types that may Include components or reaction
products;
4) The added species that are always components or other species not
present In the thermodynamlc database.
All MINTEQA1 Input files must have the first two kinds of information.
The presence of the third and fourth kinds of data is dependent upon the
specifics of the problem. In any case, it is the job of PRODEFA1 to relieve
the user of actually arranging these data in the MINTEQA1 input file by
engaging the user in a question-answer session from which the needed input
file is produced. The four basic kinds of information listed above are
discussed separately below.
INPUT FILE - Problem-Specific Constants and Options
These data are obtained by PRODEFA1 through the user's responses to
straightforward questions such as:
"Enter Title—"
"Enter Temperature Between 0 and 100 Degrees C—"
There are about twelve of these questions (the exact number will depend
upon the responses given by the user). Many of the questions require a yes
or no ("Y" or "N") resonse. It is also possible to respond with "H" for
help. PRODEFA1 will then display a brief explanation of the question and
provide an opportunity to get help on related topics.
Two questions are perhaps not as straightforward as others. One of
these is "Are all oversaturated solids allowed to precipitate?" If there are
more than 15 to 20 components in the problem, it may be wise to answer "no"
to this question. For problems that involve many components, MINTEQA1 will
find many potential solids in the thermodynamic database. Most of these will
not actually precipitate, but if the above question is answered yes, each
will continually be checked as the problem is equilibrated. This needless
complication of the problem causes longer MINTEQA1 execution times. It will
usually prove much faster to run MINTEQA1 twice for such problems. The first
run has a "no" response to the solids/precipitation question. At the end of
the MINTEQA1 output file, all of the potential solids from MINTEQAl's data-
base will be listed along with the final saturation index of each. In the
second run, the solids/precipitation question Is again answered "no", but
the species ID numbers of those solids that had positive saturation indices
are entered when PRODEFA1 asks for "Allowed Solids". The procedure for spec-
ifying "Allowed Solids" is explained below under the heading "INPUT FILE-
Other Species Types".
48
-------
The other PRODEFA1 question that is not straightforward is "Do you want
to run a debug case?" It is usually best to answer "no" to this question. A
"yes" answer causes MINTEQA1 to produce output that is only meaningful to a
person familiar with the FORTRAN source code.
Some of the PRODEFA1 queries are relevant only to problems that specify
adsorption reactions. These are used to obtain information needed for the
specific adsorption model to be used (see Chapter 4 for a description of the
six available models). Examples of the information that PRODEFA1 requests
are adsorbent concentration, specific surface area of the adsorbent, and the
electrostatic parameters for the constant capacitance and triple layer models.
The responses given by the user to questions discussed above are always
used to build the first five lines of the MINTEQA1 input file. The explana-
tion below is intended to allow the user to decipher the meaning of each of
these five lines when examining an existing input file. This is also useful
for examining MINTEQA1 output files where the input file is always repro-
duced.
Deciphering the First Five Lines of a MINTEQA1 Input File
Line 1
Line 2
Line 3
Line 4
First title line
Second title line
First entry - Temperature (C°).
Second entry - Units of concentration.
Third entry - Ionic strength (0.0 means MINTEQA1 is to
compute ionic strength).
Program option flags
First entry - Inorganic carbon input option
0 = The concentration entered for the carbonate
(COo ) component is to be treated as total
inorganic carbon.
1 = The concentration entered for the carbonate
o_
(CO^ ) component is to be treated as total
alkalinity.
Second entry - Debug print option
0 = Disable (this is the usual mode).
1-4 = Various arrays are output. Enter "H" for
help at the debug question in PRODEFA1 to
learn more.
49
-------
Line 4 - Program option flags (continued)
Third entry - Charge imbalance termination option
0 = MINTEQA1 execution terminates if charge
imbalance exceeds 30%.
1 = Execution continues regardless of charge
imbalance.
Fourth entry - Solid/precipitation output option
0 = Only those solids entered as "Allowed
Solids" are considered as potential
precipitates.
1 = All possible solids in the database are
allowed to precipitate if their saturation
indices become greater than zero. Satura-
tion indices will be output only after the
entire problem has been solved.
2 = Same as "1" except saturation indices are
output after the initial solution chemistry
has been solved and again after the entire
problem has been solved.
3 = Same as "1" except saturation indices are
output each time a solid precipitates and
after the entire problem has been solved.
Fifth entry - Total number of iterations allowed
0 =40 iterations (good first choice).
1 =10 iterations (useful for debugging).
2 = 100 iterations.
3 = 200 iterations.
Sixth entry - Constant or variable pH option
0 - pH is to be held constant. This implies
that the H+ activity is entered as a
fixed component.
1 pH is variable. Initial H+ activity
may be specified but is not entered as a
fixed component.
50
-------
Line 4 - Program option flags (continued)
Seventh entry - Ionic strength option
0 = Allow MINTEQA1 to compute the ionic strength
and to re-compute it at each iteration.
1 = Hold the ionic strength constant at the
value specified on line 3.
Eight entry - Numerical iteration method
0 = Use the Newton-Raphson method.
1 = Use a combination of the Newton-Raphson and
modified line search methods. PRODEFA1 does
not ask which method the user desires. All
input files created with PRODEFA1 use the
Newton-Raphson method only. To use the
combination method (it is sometimes helpful
with problems that fail to converge), it is
necessary to use a file editing or word
processing program to set this entry to "1".
Ninth entry — Activity coefficient option
0 = Use Debye-Huckel equation to calculate
activity coefficients.
1 = Use Davies' equation to calculate activity
coefficients. Davies' equation will be
used regardless of the option selected
when the Debye-Huckel parameters for a
species are not in the thermodynamic
database.
Tenth entry - Thermodynamic data output option
0 Do output an initial listing of data from
the database.
1 = Do not output an initial listing of the
thermodynamic data.
Line 5 - Adsorption parameters
First entry - Adsorption model option
0 = No adsorption.
1 = Activity K,j, Langmuir, Freundlich, or
Ion Exchange models.
51
-------
Line 5 - Adsorption parameters (continued)
2 = Constant Capacitance model.
3 = Triple Layer model.
Second entry - Adsorbent concentration (g/£). Valid
only for constant capacitance and triple
layer models.
Third entry - Specific surface area of adsorbent (m^/g).
Valid only for constant capacitance and
triple layer models.
Fourth entry - Inner layer capacitance (farads/m^).
Valid only for constant capacitance and
triple layer models.
Fifth entry - Outer layer capacitance (farads/m2).
Valid only for triple layer model.
Sixth entry - Not used in MINTEQA1.
INPUT FILE - Component Species
As with the first kind of MINTEQA1 input file data, every input file
must include a list of component species. Chapter 4 provides definitions of
all species types. There are currently 72 components available in PRODEFA1
and MINTEQA1 (see Table 4.1) from which the user may specify up to 45 compo-
nents (50 in the VAX version) in one MINTEQA1 run. The component species
each have a unique ID number and name. PRODEFA1 will ask whether the user
plans to identify the desired components by entering the ID numbers. If the
user doesn't know the ID number of a desired component, PRODEFA1 will ask for
the first letter in the component name and will display all components whose
name begins with that letter. This feature relieves the user of memorizing
component ID numbers. If the user is unable to identify the needed component
among those displayed, PRODEFA1 assumes this is because that component is not
in the database. PRODEFA1 then enters a series of questions that allow the
user to define a new component. (The new component will be an "added spe-
cies". The procedure for defining an added species is discussed below under
the heading "INPUT FILE - Added Species".)
After a component is selected, PRODEFA1 queries the user for the concen-
tration (in units specified earlier). After all desired components are
entered, PRODEFA1 asks for the pH and Eh if the H+ ion and the electron (e~)
components are not among those already specified. Also, depending on user
responses that follow, PRODEFA1 may add other components. For example, the
user may enter Fe^+ as a component but not Fe^"1". If the redox couple Fe-^+/
Fe2+ is subsequently entered when PRODEFA1 asks for fixed-ratio redox reac-
tions, Fe^"1" will be added to the component list at a negligible concentra-
tion. PRODEFA1 will notify the user that Fe2+ has been added. Selection of
52
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certain adsorption models also triggers automatic additions to the component
list.
PRODEFA1 sets the initial activity guess of each component to be equal
to the concentration. The value that PRODEFA1 enters in the MINTEQA1 input
file is the common logarithm of the activity guess. If a solid, fixed or
finite, is specified as initially present (an explanation of how to do this
can be found under the heading "INPUT FILE - Other Species Types"), PRODEFA1
will examine the user's input concentrations for those aqueous components
that comprise the solid and will adjust the concentrations up or down so as
to conform to the solubility product for the solid. For this reason, the
concentrations of those components in the MINTEQA1 input file may differ from
the concentrations initially specified by the user.
INPUT FILE - Other Species Types
Other species types include fixed species (those whose activities are
required to be invariant), finite solid species, allowed (potential) solid
species, and excluded species (those species that are to be excluded from
mass balance calculations in MINTEQAl). The fixed and excluded species may
include species that are also components. For example, FT1" is always a
component species but may also be a fixed species if the pH is to be held
constant. Some of the adsorption models trigger simultaneous additions to
the component species and the excluded species.
Fixed species can be components, redox couples, or gas or solid phases
(fixed solid phases are sometimes referred to as "infinite solids" to
distinguish them from finite solids). For fixed component species, PRODEFA1
enters the negative log of the activity along with the species ID and name in
the MINTEQAl input file. For gas or solid phases, or redox couples, PRODEFA1
enters the log of the equilibrium constant and the standard enthalpy change
(after giving the user an opportunity to modify them) along with the ID num-
ber and name. These values are obtained by PRODEFA1 from the thermodynamic
database after the user has identified the species by giving its ID number.
If the ID number is unknown and the species desired is a gas or redox couple,
PRODEFA1 displays a list of all gases and redox reactions in the database.
The user then selects the desired entry. If the desired species is a solid,
PRODEFA1 displays the list of major mineral groups shown in Table 5.1. The
user selects the group to which the desired solid belongs by entering the
two-digit code associated with the group. PRODEFA1 responds by asking for
the first letter in the name of the component that serves as the major cation.
When the component has been identified, PRODEFA1 searches the thermodynamic
database for all solids that meet the two identifying criteria. These are
displayed and the user selects the appropriate solid.
As was noted for component species, if the user is attempting to define
a fixed species and is unable to identify it among the possibilities displayed
on the screen, PRODEFA1 assumes this is because that species is not in the
database and a series of questions follow that allow the user to define a new
species. Upon successfully defining the new species, PRODEFA1 enters it in
the MINTEQAl input file as both a fixed species and an "added species".
53
-------
TABLE 5.1. MINERAL GROUP ID CODES USED IN FORMING SOLIDS ID NUMBERS
Mineral Group ID Numbers
00 elements
10 sulfides
20 oxides and hydroxides
30 multiple oxides
40 bromides
41 chlorides
42 fluorides
43 iodides
50 carbonates
51 nitrates
52 borates
53 chlorates
60 sulfates
61 selenites, selenates
70 phosphates
71 arsenates
73 vanadates
74 molybdates, molybdites
75 uranates
76 tungstates
80 orthosilicates
82 chain silicates
84 framework silicates
86 sheet silicates
PRODEFA1 enters all fixed species, whether they are also added species or
not, as Type 3 in the MINTEQA1 input file.
Finite solid species differ from infinite (fixed) solids in that their
activities are not held constant while the problem is equilibrated. They may
dissolve partially or completely. Thus, for finite solids, MINTEQA1 must
know the mass initially present. PRODEFA1 obtains this value from the user
and in all other respects, the procedure for defining finite solids is
identical to that for infinite solids. Finite solids are entered as Type 4 in
the MINTEQA1 input file.
As noted in the discussion concerning component species, PRODEFA1 adjusts
the concentrations of those components that comprise solids that are initially
present so as to conform to the solubility product of the solid.
Allowed or potential solids are those that are not initially present but
are to be allowed to precipitate if their solubility product is exceeded.
They differ from finite solids only in that their initial mass is zero.
They are identified to PRODEFA1 exactly as are the fixed and finite solids.
Once identified, PRODEFA1 will display the log of the equilibrium constant
and the standard enthalpy change for the user to modify if desired. PRODEFA1
enters the allowed solids as Type 5 in the MINTEQA1 input file. When, during
MINTEQAl's iterations, an allowed solid precipitates, MINTEQA1 re-assigns it
to Type 4, finite solid.
Species that might be excluded for a specific problem include one or
more of that problem's components or any species present in the thermodynamic
54
-------
database for which the necessary reactants are among the problem's compo-
nents. Excluded (or "omitted") means not included in mass balance calcula-
tions. The excluded species designation is particularly useful for those
components that are actually not chemical entities such as the electrostatic
components of the constant capacitance and triple layer adsorption models.
PRODEFA1 includes these as excluded species without user intervention when
those models are used. For other species that the user may wish to designate
as excluded (Type 6 in the MINTEQA1 input file), it is only necessary to
identify the species to PRODEFA1.
INPUT FILE - Added Species
Added species are always either components or other species that are
not present in the thermodynamic database but are needed in the problem. The
"other" species include aqueous complexes, gas or solid phases, redox couples,
and adsorption products. The one restriction that applies to all added
species is that the species to be added must be derivable from the components
(reactants) supplied in the problem (although one or more of the components
may themselves be added species). Neither components nor reactions that are
added in an input file are premanently added to the database. They exist
only for the problem for which they are added. Upon reading the input file,
MINTEQA1 treats the type 2 species as an addendum to the thermodynamic data-
base.
As noted earlier, PRODEFA1 attempts to aid the user in identifying
desired components and other species. When these attempts fail, PRODEFA1
assumes that the desired component or other species is not in the database
and asks whether the user wishes to define a new species. On a "yes" res-
ponse, PRODEFA1 proceeds through a series of questions that allow the user to
designate an ID number, name, and the necessary thermodynamic data pertinent
to the type of species being defined. The added species will be of the same
type as that which the user was attempting to identify when the "failure to
identify" occurred. For example, if the user is attempting to specify a
fixed-ratio redox couple and is unable to identify it to PRODEFA1, the series
of questions for defining a new species will be those pertinent for a redox
couple. After the redox reaction is defined with legitimate components (it
may be necessary to define one or more new components as well), the ID number
and other information pertinent to the definition of the new redox couple is
entered by PRODEFA1 as Type 3 along with any other fixed species in the
MINTEQA1 input file.
Because there are no adsorption reactions in the thermodynamic database,
PRODEFA1 always enters the question series for adding new species when an
adsorption model is used.
For added species that are defined by reactions (as opposed to component
species that are reactants), the user will be asked for the components that
comprise the reaction along with the stoichiometry of each. The reader is
referred to Chapter 4 for a description of how components are treated as
reactants and how their stoichiometry is used in MINTEQA1. The explanation
55
-------
that follows will serve to illustrate the stoichiometry of a familiar reac-
tion. This reaction is already defined in the thermodynamic database and
need not be defined as an added species in a MINTEQA1 input file.
H20
<====> H+ + OH
Should we wish to write this reaction in a way that MINTEQA1 can use, we
first note that T^O and H are already components in the database. Re-
arranging so that components are on one side and products are on the other
gives
H20 - H
OH
Thus, the stoichiometry for H in this reaction is (-1) and for H?0 is
+1. As with other features of PRODEFA1, experimentation is probably the best
teacher for learning to properly define added species.
Sample Problems
Input files for four very simple CaC03 systems will be discussed here to
illustrate the inputs required for modeling the systems similar to those dis-
cussed in Chapter 4.
1) Sy s t em A:
0.001 molar CaC03 solution, fixed pH = 9.0, no solid or gas
phases imposed, tempertaure = 20°C.
A copy of the corresponding interactive dialogue is reproduced in
Appendix B. The resulting input file is shown below.
EXAMPLE PRODEF RUN
CAC03 SOLUTION
20.00 MOL 0.00
0010000010
0 0.00 0.00 0.00
i40 l.OOOE-03 -3.00
150 l.OOOE-03 -3.00
330 O.OOOE+00 -9.00
3 1
330 9.000E+00 0.00
-Title
-Title
-Temperature, units, ionic strength
—Program option flags
0.00 -Adsorption option, parameters
-COo component
—Ca^+ component
—H component
-Begin type 3 list of 1 entry
—H+' component (fixed)
Explanatory comments are along the right side preceded by a dash.
The first two lines are title lines. Line 3 specifies the temperature
(20°C), concentration units and an indication, in the third field
(0.00), that the solution ionic strength was not "fixed." Line 4
specifies user selected execution options. The first two zeros in
Line 4 indicate that inorganic carbon was entered as carbonate rather
56
-------
than total alkalinity and that the "debug print option" was not requested.
The one (1) in the third position indicates a charge balance override
is requested. The next five zeroes indicate, respectively, that 1) only
Type 5 solids (of which there are none) should be considered for preci-
pitation, 2) the total number of iterations is to be restricted to 40,
3) the pH is to be fixed (at a value entered later), 4) the ionic
strength is not "fixed," and 5) only the Newton-Raphson iteration method
was to be used. The ninth digit, a one(l), indicates the activity
coefficients are to be calculated with the Debye-Huckel equation if the
necessary parameters are available in the database, and the zero in the
tenth position means that a printout of thermodynamic data was requested
as a part of the output.
The first zero in Line 5 indicates no sorption algorithms were to
be considered. The remaining columns for sorption parameter inputs are
therefore filled with blank entries (0.00).
2_
The first two entries beginning with Line 6 are for the COn and
Ca^+ input components which have ID numbers 140 and 150, respectively.
Each was entered at an analytical input concentration of 0.001 mol/liter
in the second column. The third column containing log activity guesses
for each component were entered by PRODEFA1. The third component H+ (ID
= 330) was necessary because all aqueous systems have access to a source
of hydronium ions resulting from dissociation of the solvent. Note that
no finite analytical input mass was necessary in this case; however, a
log activity guess of -9.0 was entered because the pH is to be fixed at
pH = 9.0.
Following a blank line, the next has a "3" and a "1" indicating
that one Type 3 species was entered. The next line contains the ID
number for H+ (330) followed by a value of 9.00 indicating that the
negative log of the H"1" activity has been fixed (invariant) at a level
corresponding to pH = 9.0. It is important to note that the second and
third columns have different uses depending on the type of species
entered. If a reaction species ID number, such as a redox couple, had
been entered in place of 330, the next two columns would have been used
to enter new log K values and enthalpies of reaction, respectively.
Also, compare these entries with those in the fixed gas phase CaC03 pro-
blem (System C). In the latter case, the second column is used for
entering the modified equilibrium constant calculated by PRODEFA1
according to the method described in Chapter 4.
2) System B: 0.001 molar CaC03 solution, floating pH, no solid or gas
phases imposed, temperature = 20°C.
The input file for this problem is given below:
EXAMPLE INPUT FILE -Title
CAC03 PROBLEM FLOATING PH -Title
20.00 MOL 0.00 -Temperature, units, ionic strength
0010000000 -Program option flags
0 0.00 0.00 0.00 0.00 0 -Adsorption option, parameters
57
-------
140 0.100E-02 -3.00
150 0.100E-02 -3.00
330 0.101E-02 -2.99
2_
+
component
component
-H component
Explanatory comments are along the right side preceded by a dash. In
this case, no fixed components were imposed. The input concentration
for the hydronium ion component (330) was derived from a fixed pH pilot
run in which the H+ input was entered as zero. The H~*" difference (i.e.,
the amount of H+ ion either generated or consumed during the reaction)
was printed in the column corresponding to the equilibrium H+ ion acti-
vity in the MINTEQA1 output.
3) System C:
0.001 molar CaC03 solution, fixed pH = 8.01, fixed CC>2
phase imposed where CO.
present, temperature = 20°C.
—3 5
= 10 * atm, no solid phases
The input file for this system is:
EXAMPLE INPUT FILE -Title
CAC03 PROBLEM WITH C02 GAS PHASE -Title
20.00 MOL 0.00 -Temperature, units, ionic strength
0010000000 -Program option flags
0 0.00 0.00 0.00 0.00 0 -Adsorption option, parameters
-COo component
-Ca^+ component
-H+ component
-Begin type 3 list of 2 entries
-C02 (g) fixed gas
-H component (fixed)
Note that an analytical value for component 002 (H20) is entered.
Also note that two fixed species are entered. The first, 3301403,
corresponds to the fixed CC>2 gas phase imposed.
C02(g) + 2H20 <==> H2C03 5.1
Using the MINEQA1 components (reactants) the corresponding reaction is
CO|~ + 2H+ - H20 <==> C02(g) 5.2
and
140
150
330
2
3 2
3301403
330
1.100E-03
l.OOOE-03
9.770E-09
5.550E+01
2.170E+01
8.010E+00
-3.00
-3.00
-8.01
1.00
-0.53
0.00
but
K =
C07] [H?0]
[H
+2
[PC02] [H20] = [PC02]
Q18.1 6
5.3
5.4
58
-------
because the activity of water = 1.0
_ O r
Assuming a fixed CO^ partial pressure of 10 * atm (the usual
atmospheric value). A new equilibrium constant K1 can then be
defined as follows to account for the fixed C02 pressure
log K1 = log K - (log 10~3'5)
= 18.16 + 3.5
s 21.7
5.5
This modified equilibrium constant (log K') is entered to the right
of ID number 3301403 in Section 3 to accommodate the fixed gas
phase. Other C02 partial pressures would be handled similarly. In
all cases the value of log K1 entered in the second column would be
18.16 minus the log of the C02 partial pressure in atmospheres.
The other fixed species is the hydronium ion component (330),
which is fixed at an activity corresponding to pH = 8.01.
4) System D:
0.001 molar CaC03 solution, pH fixed at 8.01, calcite
solid phase imposed, no C02 gas phase, temperature = 20°C.
The input file for this system as developed using PRODEFA1 is
shown below.
EXAMPLE INPUT FILE
-Title
CAC03 PROBLEM WITH SOLID PHASE (CALCITE) -Title
20.00 MOL
0.00
00100 00000
0 0.00 0.00 0.00
140 0.579E-04 0.91
150 0.579E-04
330 0.977E-08
0.00 0
0.91
-8.01
3 2
5015001 0.848E+01 2.59
330 0.801E+01 0.00
-Temperature, units, ionic
strength
-Program option flags
-Adsorption option, parameters
-CO-1 component
-Ca^+ component
-H+ component
-Begin type 3 list of 2
-Calcite (fixed solid)
-H+ component (fixed)
entries
Note that the analytical inputs for both carbonate (140) and calcium
ion (150) are not 0.001 molar. The values entered in response to
PRODEFA1 questions were 0.001 molar. PRODEFA1 made these adjustments
in response to the presence of a calcite phase. When the calcite phase
2+
2-
was imposed, the concentrations of Ca and CO^ were adjusted to con-
form to the solubility product of calcite.
Ca2 + COo2 <==> CaCOo(s)log K = 8.48
5.6
59
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The entry in column 3, line 2 corresponds to the enthalpy of reaction
for reaction 5.6. The analytical concentrations for Ca and C0o~
were calculated from the solubility products for calcite (Equation
5.6)
[Ca2+]
~] = 1(T8-48
5.7
where:
[Ca2 + ] = [CO2.-] = (1(T8-48)1/2
= 5.79 X 1CT5 molar
Line 3 of Section 3 indicates the hydronium ion activity was fixed
at a level corresponding to pH 8.01 as before.
The input files for a few more complicated systems are included in the
on-line PRODEFA1 text entries to illustrate common error responses. These
examples are accompanied by brief discussions of techniques used to isolate
and correct the error offenses.
60
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REFERENCES
1. Ball, J.W., E.A. Jenne and M.W. Cantrell. 1981. WATEQ3: A Geochemical
Model with Uranium Added. U.S. Geological Survey, Open File Report 81-
1183.
2. Benjamin, M.M. and J.O. Leckie. 1981. Multiple-Site Adsorption of Cd,
Cu, Zn, and Pb on Amorphous Iron Oxyhydroxide. J. Coll. Inter. Sci.
79:209-221.
3. Davies, C.W. 1962. Ion Association. Butterworths Pub., Washington,
DC. 190 pp.
4. Davis, J.A., R.O. James and J.O. Leckie. 1978. Surface lonization and
Complexation at the Oxide/Water Interface: I. Computation of Electrical
Double Layer Properties in Simple Electrolytes. J. Coll. Inter. Sci.
63:480-499.
5. Davis, J.A. and J.O. Leckie. 1978. Surface lonization and Complexation
at the Oxide/Water Interface: II. Surface Properties of Amorphous Iron
Oxyhydroxide and Adsorption of Metal Ions. J. Coll. Inter. Sci.
67:90-107.
6. Felmy, A.R., S.M. Brown, Y. Onishi, S.B. Yabusaki, and R.S. Argo. 1984.
MEXAMS—The Metals Exposure Analysis Modeling System. U.S. Environmental
Protection Agency, Athens, Georgia. EPA-600/3-84-031.
7. Felmy, A.R., D.C. Girvin and E.A. Jenne. 1984. MINTEQ—A Computer
Program for Calculating Aqueous Geochemical Equilibria. U.S. Environ-
mental Protection Agency, Athens, Georgia. EPA-600/3-84-032.
8. Garrels, R.M. and C.L. Christ. 1965. Solutions, Minerals, and Equilib-
ria. Freeman, Cooper and Company, San Francisco, CA.
9. Helgeson, H.C. 1969. Thermodynamics of Hydrothermal Systems at Elevated
Temperatures and Pressures. Amer. J. of Sci. 267:729—804.
10. Ingle, S.E., M.D. Schuldt and D.W. Shults. 1978. A Users Guide for
REDEQL.EPA. A Computer Program for Chemical Equilibria in Aqueous
Systems. U.S. Environmental Protection Agency, Corvallis, OR. EPA-
600/3-78-024.
11. James, R.O. and G.A. Parks. 1982. Characterization of Aqueous Colloids
by Their Electric Double-Layer and Intrinsic Surface Chemical Properties.
Surface Colloid Sci. 12:119-216.
12. Morrey, J.R. 1985. PRODEF: A Code to Facilitate the Use of the
Geochemical Code, MINTEQ. Battelle Pacific Northwest Laboratories,
Richland, Washington. (Unpublished report to U.S. Environmental
Protection Agency, Athens, Georgia.)
61
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13. Parkhurst, D.L. , D.C. Thortenson and L.N. Plummer. 1980. PHREEQE—A
Computer Program for Geochemical Calculations. U.S. Geol. Survey, Water
Resources Investigations 80-96, 210 pp.
14. Pitzer, K.S. 1973. Thermodynamics of Electrolytes. I. Theoretical
Basis and General Equations. Jour. Phys. Chem. 77:268-277.
15. Pitzer, K.S. and J.J. Kim. 1974. Thermodynamics of Electrolytes. IV.
Activity and Osmotic Coefficients for Mixed Electrolytes. J. Am. Chem.
Soc. 96:5701-5707.
16. Pitzer, K.S. and G. Mayorga. 1973. Thermodynamics of Electrolytes.
II. Activity and Osmotic Coefficients for Strong Electrolytes with Ore
or Both Ions Univalent. Jour, of Phys. Chem. 77:2300-2308.
17. Truesdell, A.H. and B.F. Jones. 1974. WATEQ, A Computer Program for
Calculating Chemical Equilibria in Natural Waters. U.S. Geol. Survey
J. Res. 2:233-248.
18. Van Zeggeren, F. and S.H. Storey. 1970. The Computation of Chemical
Equilibria. Cambridge Univ. Press, London, England.
19. Westall, J.C. 1986. MICROQL. A Chemical Equilibrium Program in BASIC.
Report No. 86-02, Oregon State University, Corvallis, OR.
20. Westall, J.C. and H. Hohl. 1980. A Comparison of Electrostatic Models
for the Oxide/Solution Interface. Adv. Coll. Inter. Sci. 12:265-294.
21. Westall, J.C., J.L. Zachary and F.M.M. Morel. 1976. MINEQL, A Computer
Program for the Calculation of Chemical Equilibrium Composition of
Aqueous Systems. Tech. Note 18, Dept. Civil Eng., Massachusetts Insti-
tute of Technology, Cambridge, MA.
22. Wolery, T.J. 1982. Computer Program for Geochemical Aqueous Specia-
tion—Solubility Calculations. Lawrence Livermore Laboratory, Livermore,
CA, 224 pp.
62
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APPENDIX A
NEWTON-RAPHSON NUMERICAL METHOD
The Newton-Raphson numeric method is an iterative technique for
finding a value x such that y(x) = 0. When only one variable is involved,
successive (improved) values of x (xn, xn+i, xn+2 ) are obtained from
the difference quotient.
xn+l - xn
= z
Al
Where the derivative evaluated at xn is denoted by zn.
In each successive step, the function y(xn+}) is set to zero (because
this is the solution sought) and Equation Al is solved for xn+j in terms of
the previously known values of xn, y(xn) and zn. When y(xn+}) in Equation
Al is set to zero
zn Ax = y(xn)
A2
Where Ax = xn+j - xn.
The new value of x is then found from:
xn+l = xn - Ax
A3
Similar reasoning applies to problems in more than one variable except
that the analog to Equation A2 becomes the matrix equation
Zn AX = Y
A4
Where Zn is the Jacobian of Y with respect to X evaluated at Xn. A solution
for AX is found trom Gaussian elimination and back substitution and Xn+j is
calculated from:
xn+l
Xn - AX
A5
63
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APPENDIX B
SAMPLE PRODEFA1 DIALOGUE FOR THE CAC03 PROBLEM
Enter Name of NEW File To Be Defined (Up To 16 Characters > TESTIN.DAT
Enter The Number Of Problems To Be Generated In This Problem File > 1
Will The NEW File Be A Modification Of An Old File? (Y,N,H) > N
Enter Title (1 Of 2 Lines) > EXAMPLE PRODEF RUN
Enter Title (2 Of 2 Lines) > CAC03 SOLUTION
Select Data Units: 1= Molal, 2= Mg/1, 3= ppm, 4= meq/1 > 1
Enter Temperature Between 0 And 100 Degrees C > 20.0
Fix Ionic Strength? (Y,N,H) > N
Enter Iteration Option: 0= 40, 1= 10, 2= 100, 3= 200 > 0
Terminate If Initial Charge Balance Off > 30% ? (Y,N,H) > N
***CAUTION: Be Aware That Answering "Y" On The Next Question And Subsequently
Adding Certain Fixed Minerals Could Cause A Phase Rule Violation.
Are All OverSaturated Solids Allowed To Precipitate? (Y,N,H) > N
Want To Run A Debug Case (Additional Output)? (Y,N,H) > N
Enter Chosen Activity Coefficient Algorithm:
0= Extended Debye-Huckel; 1= Davies > 1
Print Full Derived Species Data Base? (Y,N,H) > Y
Want To Enter Species By Identifying Number? (Y,N,H) > N
** This Section Defines The Makeup Of COMPONENT SPECIES **
ANY AQUEOUS ELEMENTS ? (Y,N,H) > Y
REMEMBER: Zero Concentration Fixes A Component Invariant
64
-------
Enter 1st Letter Of Chem. Symbol Of Wanted AQUEOUS COMPONENT (*Ends Search)>C
1 C03-2 2 CA+2 3 CD+2 4 CL-1 5 CR+2
6 CR(OH)2 7 CR04-2 8 CS+1 9 CU+1 10 CU+2
Enter Integer For Wanted AQUEOUS COMPONENT (0= NONE) > 1
Enter Concentration Of C03-2 ID # 140 In MOL > .001
140 C03-2 Has Been Modified Or Added To File 1
Enter 1st Letter Of Chem. Symbol Of Wanted AQUEOUS COMPONENT (*Ends Search)>C
1 C03-2 2 CA+2 3 CD+2 4 CL-1 5 CR+2
6 CR(OH)2 7 CR04-2 8 CS+1 9 CU+1 10 CU+2
Enter Integer For Wanted AQUEOUS COMPONENT (0= NONE) > 2
Enter Concentration Of CA+2 ID # 150 In MOL > .001
150 CA+2 Has Been Modified Or Added To File 1
Enter 1st Letter Of Chem. Symbol Of Wanted AQUEOUS COMPONENT (*Ends Search)>H
1 H20 2 H3AS03 3 H3AS04 4 H3B03 5 HUMATE
6 H+l 7 HG2+2 8 HG(OH)2 9 HS-1 10 HSE-1
11 HSE03-1 12 H4SI04
Enter Integer For Wanted AQUEOUS COMPONENT (0= NONE) > 6
Enter Concentration Of H+l ID # 330 In MOL > 0.0
Enter Fixed Positive Activity Of H+l In Moles/KG H20 >.1E-08
330 H+l Has Been Modified Or Added To File 1
Enter 1st Letter Of Chem. Symbol Of Wanted AQUEOUS COMPONENT (*Ends Search)>*
Enter P For pE, E For Eh, N For Neither, H For Help> N
** This Section Defines The Makeup Of GASEOUS SPECIES **
ANY FIXED GASES ? (Y,N,H) > N
** This Section Defines The Makeup Of ADSORPTION PROBLEM**
ANY ADSORPTION DEFINIT°N? (Y,N,H) > N
** This Section Defines The Makeup Of REDOX SPECIES **
ANY FIXED-RATIO REDOX ? (Y,N,H) > N
** This Section Defines The Makeup Of MINERAL SPECIES **
ANY INFINITE SOLIDS ? (Y,N,H) > N
65
-------
** This Section Defines Solids Initially Present**
ANY FINITE SOLIDS ? (Y,N,H) > N
** This Section Defines Specific Solids That Could Form**
ANY ALLOWED SOLIDS ? (Y,N,H) > N
** This Section Defines Species That Will Be Excluded From The Calculations **
ANY EXCLUDED SPECIES ? (Y,N,H) > N
Any Other Database Modifications Or Additions? (Y,N,H) > N
Listing Of COMPONENT Follows For Verification Or Change
I. D. TOTAL CONC°N LOGIO(ACT)
1 140 1.00000E-03-3.00000E+00 C03-2
2 150 1.00000E-03-3.00000E+00 CA+2
3 330 O.OOOOOE+00-9.00000E+00 H+l
Enter Line # To Change, Add Or Delete (0= Done) > 0
No AQUEOUS SPECIES (TYPE 2) Have Been Defined.
Listing Of FIXED SPECIES Follows For Verification Or Change
I. D. LOGIO(KEQ) DELTA H REAC
1 330 9.00000E+00 O.OOOOOE+00 H+l
Enter Line # To Change, Add Or Delete (0= Done) > 0
No FINITE SOLID (TYPE 4) Have Been Defined.
No POTENTIAL SOLIDS (TYPE 5) Have Been Defined.
No OMITTED SPECIES (TYPE 6) Have Been Defined.
No ADDED SPECIES (TYPE 7) Have Been Defined.
Any Other Detailed Changes In Definition Of Problem ? (Y,N) > N
A Problem File Named TESTIN.DAT Has Now Been Generated.
It Can Be Modified By This Same Program By Recalling It As The Old File.
EXAMPLE PRODEF RUN
CAC03 SOLUTION
T = 20.00 MOL 0.00
0010000010
0 0.00 0.00 0.00 0.00
140 l.OOOE-03 -3.00
150 l.OOOE-03 -3.00
330 O.OOOE+00 -9.00
H20 HAS BEEN INSERTED AS A COMPONENT
3 1
330 9.000E+00 0.00
66
-------
APPENDIX C
THE THERMODYNAMIC DATABASE USED BY MINTEQAl
Some important constants from the thermodynamic database used by
MINTEQAl are presented in the following tables along with the species ID
numbers. This is not a listing of the database itself. The actual database
has the stoichiometry of the components involved in each reaction as well as
other constants. The table is subdivided into five parts:
1) Component Species
2) Aqueous Complexes
3) Solid Species
4) Redox couples
5) Gas phases
Concerning the notation used in naming the species, because FORTRAN does
not support the use of super- or subscripts, the customary method of writing
chemical formulas cannot be accommodated without modification. The following
naming rules are used in MINTEQAl:
1) Stoichiometric coefficients are written with parentheses and brackets
enclosing the elements in the formula to which the stoichiometry
applies. The Stoichiometric coefficient itself will never be preceded
with a sign (+/-).
2) Species charge numbers will always be preceded with a sign (+/-).
The one (1) in (+1) and (-1) may be omitted. If a species name ends
with an unsigned number, that number represents stoichiometry, not
oxidation
state.
3) Species names involving organics may be shortened by leaving out
letters.
Examples:
H20 means H20
CR(OH)2+ means Cr(OH)2+
HG(OH)2 means Hg(OH)2
S04-2 means S0^2~
TARTRAT means Tartrate
67
-------
Species
ID Number
001
002
020
030
060
061
090
100
130
140
141
142
143
144
145
146
147
148
150
160
180
210
211
212
220
230
231
270
280
281
330
360
361
380
410
440
460
470
471
490
491
492
Name
************
E-l
H20
AG+1
AL+3
H3AS03
H3AS04
H3B03
BA+2
BR-1
C03-2
FULVATE
HUMATE
ACETATE
TARTRAT
GLYCINE
SALICYL
GLUTAMA
PHTHALA
CA+2
CEH-2
CL-1
CR+2
CR(OH)2+
CR04-2
CS+1
CU+1
CU+2
F-l
FE+2
FE+3
H+l
HG2+2
HG(OH)2
1-1
K+l
LI+1
MG+2
MN+2
MN+3
NH4+1
N02-1
N03-1
Species
Charge
Component Species
-1.0
0.0
1.0
3.0
0.0
0.0
0.0
2.0
-1.0
-2.0
-2.0
-2.0
-1.0
-2.0
-1.0
-2.0
-2.0
-2.0
2.0
2.0
-1.0
2.0
1.0
-2.0
1.0
1.0
2.0
-1.0
2.0
3.0
1.0
2.0
0.0
-1.0
1.0
1.0
2.0
2.0
3.0
1.0
-1.0
-1.0
Gram Formula
Weight
***********
0.0000
18.0153
107.868
26.9815
125.9437
141.9431
61.8331
137.3400
79.9040
60.0094
650.0000
2000.0000
59.05
1^8.09
74.07
136.12
145.13
164.13
40.0800
112.3994
35.4530
51.996
86.011
115.994
132.905
63.5460
63.5460
18.9984
55.8470
55.8470
1.0080
401.18
234.61
126.9044
39.1020
6.9390
24.3120
54.9380
54.9380
18.0386
46.0055
62.0049
68
-------
Species
ID Number
500
540
580
600
680
730
731
732
760
761
762
770
800
870
871
891
890
892
893
900
901
902
903
950
990
991
992
993
994
995
Name
************
NA+1
NI+2
P04-3
PB+2
RB+1
HS-]
S
S04-2
HSE-1
HSE03-1
SE04-2
H4SI04
SR+2
TL+1
TL(OH)3
U+4
U+3
U02 + 1
U02+2
V+2
V+3
VO+2
V02+1
ZN+2
SOH1
SOH2
XPSIO
XPSIB
XPSID
SOHB
Species
Charge
Component Species
1.0
2.0
-3.0
2.0
1.0
-1.0
0.0
-2.0
-1.0
-1.0
-2.0
0.0
2.0
1.0
0.0
4.0
3.0
1.0
2.0
2.0
3.0
2.0
1.0
2.0
0.0
0.0
0.0
0.0
0.0
0.0
Gram Formula
We i gh t
***********
22.9898
58.7100
94.9714
207.1899
85.4699
33.0720
32.0640
96.0616
79.97
127.97
142.96
96.1155
87.6200
204.37
255.39
238.0290
238.0290
270.0278
270.0278
50.94
50.94
66.939
82.939
65.3699
0.0
0.0
0.0
0.0
0.0
0.0
69
-------
Species
ID Numbe r
3300020
3307700
3307701
7702700
3300900
902700
902701
902702
902703
3304900
4907320
4603300
4602700
4601400
4601401
4607320
4605800
4605801
4605802
1503300
1501400
1501401
1507320
1505800
1505801
1505802
1502700
5001400
5003401
5007320
5005800
5002700
4107320
4105800
303300
303301
303302
302700
302701
302702
302703
307320
Name
A****************
K OH-
KH3SI04 -
KH2SI04 -2
KSIF6 -2
KH2B03 -1
KBF(OH)3 -
KRF2(OH)2 -
KBF30H -
KBF4 -
KNH3 AQ
KNH4S04 -
KMGOH +
KMGF +
KMGC03 AQ
KMGHC03 +
KMGS04 AQ
KMGP04 -
KMGH2P04 +
KMGHP04 AQ
KCAOH +
KCAHC03 +
KCAC03 AQ
KG AS 04 AQ
KCAHP04 AQ
KCAP04 -
KCAH2P04 +
KCAF +
KNAC03 -
KNAHC03 AQ
KNAS04 -
KNAHP04 -
KNAF AQ
KKS04 -
KKHP04 -
KALOH +2
KAL(OH)2 +
KAL(OH)4 -
KALF +2
KALF2 +
KALF3 AQ
KALF4 -
KALS04 +
Standard
Enthalpy
Reaction
Aqueous
13.3450
8.9350
29.7140
-16.2600
3.2240
1.8500
1.6350
-1.5800
-1.7950
12.4800
0.0000
15.9350
4,6740
2.0220
-2.4300
1.3990
3.1000
-1.1200
-0.2300
14.5350
1.7900
4.0300
1.4700
-0.2300
3.1000
-1.1200
3.7980
8.9110
0.0000
1.1200
0.0000
0.0000
2.2500
0.0000
11.8990
0.0000
44.0600
0.0000
20.0000
2.5000
0.0000
2.1500
of
Log K
Gram Formula
Weight
Complexes **************
-13.9980
-9.9300
-21.6190
30.1800
-9.2400
-0.3990
7.6300
13.6670
20.2740
-9.2520
1.1 100
-1 1.7900
1.8200
2.9800
11.4000
2.2500
6.5890
21.0660
15.2200
-12.5980
11.3300
3.1500
2.3090
15.0850
6.4590
20.9600
0.9400
1.2680
10.0800
0.7000
12.6360
-0.7900
0.8500
12.6400
-4.9900
-10.1000
-23.0000
7.0100
12.7500
17.0200
19.7200
3.0200
17.0074
95.1070
94.0990
142.0760
60.8250
80.8310
82.8220
84.8130
86.8040
17.0300
114.1000
41.3190
43.3100
84.3210
85.3290
120.3730
119.2830
121.2990
120.2910
57.0870
101.0970
100.0890
136.1410
136.0590
135.0510
137.0670
59.0780
82.9990
84.0070
119.0510
118.9690
41.9880
135.1630
135.0810
43.9880
60.9960
95.0110
45.9790
64.9780
83.9760
102.9750
123.0430
70
-------
Species
ID Number
307321
303303
2803300
2803301
2807320
2805800
2803302
2805801
2807300
2807301
2813300
2815800
2817320
2811800
2811801
2811802
2813301
2813302
2813303
2815801
2812700
2812701
2812702
2817321
2811410
2811420
2813304
2813305
4407320
8003300
1003300
4701800
4701801
4701802
4703300
4703301
4702700
4707320
4704920
4701400
4700020
4700021
2301800
2301801
Name
*****************
KAL(S04)2 -
KAL(OH)3 AQ
KFEOH +
KFEOH3 -1
KFES04 AQ
KFEH2P04 +
KFEOH2 AQ
KFEHP04 AQ
KFE(HS)2 AQ
KFE(HS)3 -
KFEOH +2
KFEHP04 +
KFES04 +
KFECL +2
KFECL2 +
KFECL 3 AQ
KFEOH2 +
KFEOH3 AQ
KFEOH4 -
KFEH2P04 +2
KFEF +2
KFEF2 +
KFEF3 AQ
KFE(S04)2 -
KFE FULVATE
KFE HUMATE
KFE2(OH)2+4
KFE3(OH)4+5
KLIS04 -
KSROH +
KBAOH +
KMNCL +
KMNCL2 AQ
KMNCL3 -
KMNOH +
KMN(OH)3 -1
KMNF +
KMNS04 AQ
KMN(N03)2AQ
KMNHC03 +
KMN04 -
KMN04 -2
KCUCL2 -
KCUCL3 -2
Standard
Enthalpy
React! on
Aqueous
2.8400
0,0000
13.1990
30.3000
3.2300
0.0000
28.5650
0.0000
0.0000
0.0000
10.3990
-7.3000
3.9100
5.6000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
2.6990
4.8000
5.3990
4.6000
0.0000
0.0000
13.5000
14.3000
0.0000
14.4950
15.0950
0.0000
0.0000
0.0000
14.3990
0.0000
0.0000
2.1700
-0.3960
0.0000
176.6200
150.0200
-0.4200
0.2600
of
Log K
Gram Formula
We i gh t
Complexes **************
4.9200
-16.0000
-9.5000
-31.0000
2.2500
22.2530
-20.5700
15.9500
8.9500
10.9870
-2.1900
17.7800
3.9200
1.4800
2.1300
1.1300
-5.6700
-13.6000
-21.6000
24.9800
6.1990
10.8000
14.0000
5.4200
9.3990
9.3990
-2.9500
-6.3000
0.6400
-13.1780
-13.3580
0.6070
0.0410
-0.3050
-10.5900
-34.8000
0.8500
2.2600
0.6000
11.6000
-127.8240
-118.4400
5.5000
5.7000
219.1040
78.0030
72.8540
106.8690
151.9080
152.8340
89.8610
151.8260
121.9900
155.0620
72.8540
151.8260
151.9080
91.3000
126.7530
162.2060
89.8610
106.8690
123.8760
152.8340
74.8450
93.8430
112.8420
247.9700
705.8470
2055.8459
145.7080
235.5700
103.0000
104.6270
154.3470
90.3910
125.8440
161.2970
161.2970
105.9600
73.9360
150.9990
178.9470
115.9550
118.9350
118.9350
134.4520
169.9050
71
-------
Species
ID Number
2307300
2307301
2301431
2301451
2301452
2301461
2301462
2301471
2301472
2301481
2301482
2311400
2311401
2311800
2311801
2311802
2311803
2312700
2313300
2313301
2313302
2313303
2313304
2317320
2317300
2311402
2311410
2311420
9501800
9501801
9501802
9501803
9502700
9503300
9503301
9503302
9503303
9501804
9507300
9507301
9507320
9507321
9501300
9501301
Name
*****************
KCU(S4)2 -3
KCUS4S5 -3
KCU ACETATE
KCU GLYCINE
KCU GLYCINE
KCU SALICYL
KCU SALICYL
KCU GLTJTAMA
KCU GLUTAMA
KCU PHTHALA
KCU PHTHALA
KCUC03 AQ
KCU(C03)2-2
KCUCL +
KCUCL2 AQ
KCUCL3 -
KCUCL4 -2
KCUF +
KCUOH +
KCU(OH)2 AQ
KCU(OH)3 -
KCU (OH) 4 -2
KCU2(OH)2+2
KCUS04 AQ
KCU(HS)3 -
KCUHC03 +
KCU FULVATE
KCU HUM ATE
KZNCL +
KZNCL2 AQ
KZNCL3 -
KZNCL4 -2
KZNF +
KZNOH +
KZN(OH)2 AQ
KZN(OH)3 -
KZN(OH)4 -2
KZNOH CL AQ
KZN(HS)2 AQ
KZN(HS)3 -
KZNS04 AQ
KZN(S04)2-2
KZNBR +
KZNBR2 AQ
Standard
Enthalpy
Reaction
Aqueous
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
8.6500
10.5600
13.6900
17.7800
1.6200
0.0000
0.0000
0.0000
0.0000
17.5390
1.2200
0.0000
0.0000
0.0000
0.0000
7.7900
8.5000
9.5600
10.9600
2.2200
33.3990
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
1.3600
0.0000
0.0000
0.0000
of
Log K
Gram Formula
Weight
Complexes **************
3.3900
2.6600
2.2400
8.6200
6.9700
10.6400
6.3000
7.8500
6.5500
3.4600
1.3700
6.7300
9.8300
0.4300
0.1600
-2.2900
-4.5900
1.2600
-8.0000
-13.6800
-26.8990
-39.6000
-10.3590
2.3100
25.8990
13.0000
6.1990
6.1990
0.4300
0.4500
0.5000
0.1990
1 . 1 500
-8.9600
-16.8990
-28.3990
-41.1990
-7.4800
14.9400
16.1000
2.3700
3.2800
-0.5800
-0.9800
320.0580
352.1220
122.5900
137.6100
201.1500
199.6600
263.2000
208.6700
272.2100
227.6700
291.2100
123.5550
183.5640
98.9990
134.4520
169.9050
205.3580
82.5440
80.5530
97.5600
114.5680
131.5750
161.1060
159.6070
162.7610
124.5630
713.5460
2063.5449
100.8230
136.2760
171.7290
207.1820
84.3680
82.3770
99.3840
116.3920
133.3990
117.8300
131.5130
164.5850
161.4310
257.4930
145.2740
225.1780
72
-------
Species
ID Number
9503800
9503801
9501400
9501401
9501402
1601800
1601801
1601802
1602700
1602701
1601400
1603300
1603301
1603302
1603303
1603304
1601803
1604920
1607320
1607300
1607301
1607302
1607303
1601300
1601301
1603800
1603801
1601400
1601401
1607321
1601410
1601420
6001800
6001801
6001802
6001803
6001400
6002700
6002701
6002702
6002703
6003300
6003301
6003302
Name
*****************
KZNI +
KZNI2 AQ
KZNHC03 +
KZNC03 AQ
KZN( 003)2-2
KCDCL +
KCDCL2 AQ
KCDCL3 -
KCDF +
KCDF2 AQ
KCD(C03)3-4
KCDOH +
KCD(OH)2 AQ
KCD(OH)3 -
KCD(OH)4 -2
KCD20H +3
KCDOHCL AQ
KCDN03 +
KCDS04 AQ
KCDHS +
KCD(HS)2 AQ
KCD(HS)3 -
KCD(HS)4 -2
KCDBR +
KCDBR2 AQ
KCDI +
KCDI2 AQ
KCDHC03 +
KCDC03 AQ
KCD(S04)2-2
KCD FULVATE
KCD HUMATE
KPBCL +
KPBCL2 AQ
KPBCL3 -
KPBCL4 -2
KPB(C03)2-2
KPBF +
KPBF2 AQ
KPBF3 -
KPBF4 -2
KPBOH +
KPB(OH)2 AQ
KPB(OH)3 -
Standard
Enthalpy
Reaction
Aqueous
0.0000
0.0000
0.0000
0.0000
0.0000
0.5900
1.2400
3.9000
0.0000
0.0000
0.0000
13.1000
0.0000
0.0000
0.0000
10.8990
4.3550
-5.2000
1.0800
0.0000
0.0000
0.0000
0.0000
-0.8100
0.0000
-2.3700
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
4.3800
1.0800
2.1700
3.5300
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
of
Log K
Gram Formula
Weight
Complexes **************
-2.9100
-1.6900
12.4000
5.3000
9.6300
1.9800
2.6000
2.3990
1.1000
1.5000
6.2200
-10.0800
-20.3500
-33.3000
-47.3500
-9.3900
-7.4040
0.3990
2.4600
10.1700
16.5300
18.7100
20.9000
2.1700
2.8990
2.1500
3.5900
12.4000
5.3990
3.5000
3.5000
3.5000
1.6000
1.8000
1.6990
1.3800
10.6400
1.2500
2.5600
3.4200
3.1000
-7.7100
-17.1200
-28.0600
192.2740
319.1780
126.3570
125.3790
185.3580
147.8530
183.3060
218.7590
131.3980
150.3960
292.4280
129.4070
146.4140
163.4220
180.4290
241.8074
164.8600
174.4040
208.4610
145.4720
178.5430
211.6150
244.6870
192.3040
272.2080
239.3040
366.2080
173.4170
172.4090
208.4610
762.3990
2112.3989
242.6430
278.0960
313.5490
349.0020
327.2080
226.1880
245.1860
264.1850
283.1830
224.1970
241.2040
258.2120
73
-------
Species
ID Number
6003303
6004920
6007320
6007300
6007301
6003304
6001300
6001301
6003800
6003801
6001401
6003305
6007321
6001402
5401300
5401800
5402700
5403300
5403301
5403302
5407320
5401801
5401400
5401401
5401402
5407321
5401431
5401451
5401452
5401461
5401462
5401471
5401572
5401481
201300
201301
201800
201801
201802
201803
202700
207300
207301
203800
Name
*****************
KPB20H +3
K PEN 03 +
KPRS04 AQ
KPB(HS)2 AQ
KPB(HS)3 -
KPB3(OH)4+2
KPBBR +
KPBBR2 AQ
KPBI +
KPBI2 AQ
KPBC03 AQ
KPB(OH)4 -2
KPB(S04)2-2
KPBHC03 +
KNIBR +
KNICL +
KN1F +
KNIOH +
KNI(OH)2 AQ
KNI(OH)3 -
KNIS04 AQ
KNICL2 AQ
KNIHC03 +
KNIC03 AQ
KNI(C03)2-2
KNI(S04)2-2
KNI ACETATE
KNI GLYCINE
KNI GLYCINE
KNI SALICYL
KNI SALICYL
KNI GLUTAMA
KNI GLUTAMA
KNI PHTHALA
KAGBR AQ
KAGBR2 -
KAGCL AO
KAGCL2 -
KAGCL3 -2
KAGCL4 -3
KAGF AQ
KAGHS AQ
KAG(HS)2 -
KAGI AQ
Standard
En t ha 1 p y of
Reaction
Aqueous Com\
0.0000
0.0000
0.0000
0.0000
0.0000
26.5000
2.8800
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
12.4200
0.0000
0.0000
1.5200
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
-2.6800
-3.9300
0.0000
0.0000
-2.8300
0.0000
0.0000
0.0000
Log K
Gram Formula
Weight
ilexes **************
-6.3600
1.1700
2.7500
15.2700
16.5700
-23.8800
1.7700
1.4400
1.9400
3.1990
7.2400
-39.6990
3.4700
13.2000
0.5000
0.3990
1.3000
-9.8600
-19.0000
-30.0000
2.2900
0.9600
12.4700
6.8700
10.1100
1.0200
1.1200
6.1800
4.9600
6.9500
4.8000
5.9000
4.4400
2.1000
4.2400
7.2800
3.2700
5.2700
5.2900
5.5100
0.3600
14.0500
18.4500
6.6000
431.3870
269.1940
303.2510
273.3330
306.4050
689.5990
287.0940
366.9980
334.0940
460.9980
267.1990
375.2190
399.3130
268.2070
138.6140
94.1630
77.7080
75.7170
92.7240
109.7320
154.7710
129.6160
119.7270
118.7190
178.7280
250.8330
117.7600
132.7800
191.4900
194.8300
253.5400
203.8400
262.5500
222.8400
187.7720
267.6760
143.3210
178.7740
214.2270
249.6790
126.8660
140.9390
174.0110
234.7720
74
-------
Species
ID Number
203801
203300
203301
207320
204920
204910
201302
203802
203803
207302
207303
207304
201410
201420
3300600
3300601
3300602
3300610
3300611
3300612
3300613
3301400
3301401
3307320
3302700
3302701
3302702
3305800
3305801
3307300
3307301
3301410
3301420
8913300
8913301
8913302
8913303
8913304
8912700
8912701
8912702
8912703
8912704
8912705
Name
*****************
KAGI2 -
KAGOH AQ
KAG(OH)2 -
KAGS04 -
KAGN03 AQ
KAG(N02)2 -
KAGBR3 -2
KAGI3 -2
KAGI4 -3
KAG(S4)2 -3
KAGS4S5 -3
KAG(HS)S4-2
KAG FULVATE
KAG HUMATE
KH2AS03 -
KHAS03 -2
KAS03 -3
KH4AS03 +
KH2AS04 -
KHAS04 -2
KAS04 -3
KHC03 -
KH2C03 AQ
KHS04 -
KHF AQ
KHF2 -
KH2F2 AQ
KHP04 -2
KH2P04 -
KH2S AQ
KS -2
KH FULVATE
KH HUMATE
KUOH +3
KU(OH)2 +2
KU(OH)3 +1
KU(OHH AQ
KU(OH)5 -1
KUF +3
KUF2 +2
KUF3 +1
KUF4 AQ
KUF5 -1
KUF6 -2
Standard
Enthalpy
Reaction
Aqueous
0.0000
0.0000
0.0000
1.4900
0.0000
0.0000
0.0000
-27.0300
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
6.5600
14.1990
20.2500
0.0000
-1.6900
-0.9200
3.4300
-3.6170
-2.2470
4.9100
3.4600
4.5500
0.0000
-3.5300
-4.5200
-5.3000
12.1000
0.0000
0.0000
11.7150
17.7300
22.6450
24.7600
27.5750
5.0500
7.2000
7.1500
4.6000
4.8500
3.3000
75
of
Log K
Gram Formula
Weight
Complexes **************
10.6800
-12.0000
-24.0000
1.2900
-0.2900
2.2200
8.7100
13.3700
14.0800
0.9910
0.6800
10.4310
2.3990
2.3990
-9.2280
-21.3300
-34.7440
-0.3050
-2.2430
-9.0010
-20.5970
10.3300
16.6810
1.9870
3.1690
3.7490
6.7680
12.3460
19.5530
6.9940
-12.9180
4.2700
4.2700
-0.6560
-2.2700
-4.9350
-8.4980
-13.1200
8.6590
14.4570
19.1150
23.6400
25.2380
27.7180
361.6760
124.8750
141.8820
203.9290
169.8720
199.8790
347.5800
488.5810
615.4850
364.3800
396.4440
269.1960
757.8680
2107.8669
124.9350
123.9270
122.9190
126.9510
140.9350
139.9270
138.9190
61.0170
62.0250
97.0690
20.0060
39.0040
40.0120
95.9790
96.9870
34.0790
32.0640
651.0080
2001.0070
255.0364
272.0437
289.0511
306.0586
323.0659
257.0274
276.0258
295.0242
314.0226
333.0210
352.0194
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
***************** Aqueous Complexes **************
8911800
8917320
8917321
8915800
8915801
8915802
8915803
8933300
8933301
8933302
8931400
8931401
8931402
8932700
8932701
8932702
8932703
8931800
8937320
8937321
8935800
8935801
8935802
8935803
8935804
8937700
7317300
7317301
7317302
7317303
7317304
9003300
9013300
9013301
9013302
9017320
9013303
9013304
9023300
9023301
9022700
9022701
9022702
9022703
KUCL +3
KUS04 +2
KU(S04)2 AQ
KUHP04 +2
KU(HP04)2AQ
KU(HP04)3-2
KU(HP04)4-4
KU020H +1
KU02)20H2+2
KU02)30H5+1
KU02C03 AQ
KU02C03)2-2
KU02C03)3-4
KU02F +1
KU02F2 AQ
KU02F3 -1
KU02F4 -2
KU02CL +1
KU02S04 AQ
KU02S04)2-2
KU02HP04 AQ
KU02HP04)2
KU02H2P04+1
KU02H2P04)2
KU02H2P04)3
KU02H3SI04
KS2 -2
KS3 -2
KS4 -2
KS5 -2
KS6 -2
VOH +
VOH +2
V(OH)2 +1
V(OH)3 AQ
VS04 +1
V2(OH)3 +3
V2(OH)2 +4
V(OH)3 +1
H2V204 +2
VOF +
VOF2 AQ
VOF3 -1
VOF4 -2
9.9330
3.7000
7.6000
7.5000
1.7000
-7.8000
-26.5000
10.2160
10.2300
25.0750
0.8400
3.4800
-8.7800
-0.4500
-0.9000
-0.8500
-1.1000
1.2330
5.1000
6.1000
-2.1000
-11.3990
-3.7000
-16.5000
-28.6000
0.0000
11.4000
10.4000
9.7000
9.3000
0.0000
0.0000
9.3500
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
1.9000
3.5000
4.9000
6.4000
1.3380
5.4610
9.7490
24.4430
46.8330
67.5640
88.4830
-5.0900
-5.6450
-15.5930
10.0710
17.0080
21.3840
5.1050
8.9200
11.3640
12.6070
0.2200
2.7090
4.1830
20.8140
42.9880
22.6430
44.7000
66.2450
-2.4000
-14.5280
-13.2820
-9.8290
-9.5950
-9.8810
-5.6400
-2.3000
-5.8300
-11.0200
1.4400
-7.5000
-3.7500
-5.6700
-6.4400
3.3400
5.7400
7.3000
8.1100
273.4820
334.0906
430.1522
334.0084
429.9877
525.9671
621.9465
287.0352
574.0703
895.1203
330.0372
390.0465
450.0559
289.0262
308.0246
327.0230
346.0214
305.4808
366.0894
462.1510
366.0072
461.9865
367.0151
464.0020
560.9890
365.1350
64.1280
96.1920
128.2360
160.3200
192.3840
67.9470
67.9470
84.9550
101.9620
146.9980
152.9020
135.8950
101.9620
167.8940
85.9370
104.9350
123.9330
142.9310
76
-------
Species
ID Number
9027320
9021800
9033300
9033301
9033302
9033303
9030020
9030021
9030022
9030023
9030024
9030025
9030026
9030027
9032700
9032701
9032702
9032703
9037320
9034920
8703300
8702700
8701800
8701801
8701300
8701301
8701302
8703800
8703801
8703802
8707320
8704920
8704910
8707300
8707301
8707302
8707303
8713300
8713301
8713302
8711800
8711801
8711802
8711803
Name
*****************
VOS04 AQ
VOCL +1
H3V04 AQ
H2V04 -1
HV04 -2
V04 -3
V207 -4
HV207 -3
H3VZU/ -1
V309 -3
V4012 -4
V10028 -6
HV10028 -5
H2V10028 -4
V02F AQ
V02F2 -1
V02F3 -2
V02F4 -3
V02S04 -1
V02N03 AQ
T10H AQ
TIP AQ
T1C1 AQ
T1C12-1
TIBr AQ
TlBr2-l
TlBrCl-1
Til AQ
T1I2-1
TlIBr-1
T1S04-1
T1N03 AQ
T1N02 AQ
T1HS AQ
T12HS+1
T120H(HS)3-
T12(OH)2(HS
Tl+3
T10H+2
T1(OH)2+1
T1C1+2
T1C12+1
T1C13 AQ
T1C14-1
Standard
Enthalpy
Reaction
Aqueous
3.7200
0.0000
10.6300
11.3300
14.9300
19.5300
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
21.5200
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
13.9350
0.0000
-1.1470
0.0000
-2.4610
2.9980
0.0000
0.0000
0.0000
0.0000
-0.2200
-0.6500
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
of
Log K
Gram Formula
Weight
Complexes **************
2.4500
0.0200
-3.3000
-7.0900
-15.1500
-28.4000
-29.0800
-16.3200
-3.7900
-15.8800
-20.7900
-17.5300
-11.3500
-7.7100
3.1200
5.6700
6.9700
7.0700
1.7100
-0.4300
-13.1717
-0.4251
0.6824
0.2434
0.9477
0.9719
0.8165
1.4279
1.8588
2.1850
1.3853
0.3665
0.9969
1.8178
7.6979
1.0044
-11.0681
4.7424
3.5770
2.1183
12.2342
18.0402
21.4273
24.2281
162.9970
102.3920
117.9620
116.9540
115.9460
114.9380
213.8760
214.8840
216.9000
296.8150
395.7530
957.3830
958.3910
959.3990
101.9370
120.9350
139.9330
158.9310
178.9960
144.9440
221.3773
223.3684
239.8230
275.2760
284.2740
364.1780
319.7270
331.2745
458.1790
411.1785
300.4276
266.3749
250.3755
237.4379
441.8079
524.9510
508.8904
204.3700
221.3773
238.3846
239.8230
275.2760
310.7290
346.1820
77
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
*****************
Aqueous Complexes
**************
8711300
8711301
8711302
8711303
8713800
8714920
8713303
8711804
3307601
3307600
4707600
207600
207601
3307611
3307610
2817610
207610
207611
1607610
3307620
4707620
2007620
5407620
1607620
9507620
9507621
3600000
3613300
3611301
3611302
3611303
3611304
3611305
3611306
3611307
3611308
3611309
3613301
3611800
3611801
3811802
3611803
3611804
3611805
TlBr+2
TLBr2+l
TlBr3 AQ
TlBr4-l
T1I4-1
T1N03+2
T1(OH)4-1
T10HC1+1
Se-2
H2Se
MnSe
Ag2Se
AgOH(Se)2-4
Se03-2
H2Se03
FeHSe03+2
AgSe03-l
Ag(Se03)2-3
Cd(Se03)2-2
HSe04-l
MnSe04
CoSe04
NiSe04
CdSe04
ZnSe04
Zn(Se04)2-2
Hg (aq)
Hg+2
HgBr+
HgBr2 (aq)
HgBr3-l
HgBr4-2
HgBrCl (aq)
HgBrI (aq)
HgBrl3-2
HgBr2I2-2
HgBr3l-2
HgBrOH (aq)
HgCl+1
HgC12 (aq)
HgCl3-l
HgC14-2
HgClI (aq)
HgClOH (aq)
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
11.5000
0.8000
0.0000
0.0000
0.0000
1.2800
1.6900
0.0000
0.0000
0.0000
0.0000
4.2000
3.4600
2.9100
3.5000
0.0000
0.0000
0.0000
-16.6050
-11.0600
0.0000
-30.8320
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
-12.4820
14.2221
21.5761
27.0244
31.1533
34.7596
7.0073
-10.2545
10.6290
-14.9529
3.8115
-6.7435
34.0677
-18.6237
-7.3005
2.5728
1.8618
-5.5985
-10.9933
-11.1890
1.9058
2.4188
2.7120
2.6387
2.2415
2.2019
-0.0704
6.9316
6.0970
15.8347
23.6065
25.7857
27.0633
22.0145
27.1212
34.2135
32.3994
30.1528
11.5980
12.8500
19.2203
20.1226
20.5338
25.3532
9.3170
284.2740
364.1780
444.0820
523.9860
711.9880
266.3749
272.3992
256.8303
78.9600
80.9758
133.8980
294.6960
282.7953
126.9582
128.9740
183.8131
234.8262
361.7844
366.3264
143.9655
197.8956
201.8908
201.6576
255.3676
208.3376
351.2952
200.5900
200.5900
280.4940
360.3980
440.3020
520.2060
315.9470
407.3985
661.2075
614.2070
567.2065
297.5013
236.0430
271.4960
306.9490
342.4020
362.9475
253.0503
78
-------
Species
ID Numbe r
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
3612701
3613801
3613802
3613803
3613804
3614900
3614901
3614902
3614903
3614920
3614921
3613302
3613303
3617300
3617301
3617320
3611401
3611402
2113300
2113301
2110020
2110021
2113304
2111300
2111800
2111801
2111802
2112700
2113800
2114900
2114901
2114902
2114903
2114904
2114905
2114906
2114920
2115800
2117320
2117321
2117322
2117323
2117324
HgF+1
HGI+1
Hgl2 (aq)
Hgl3-l
Hgl4-2
HgNH3+2
Hg(NH3)2+2
Hg(NH3)3+2
Hg(NH3)4+2
HgN03+l
Hg(N03)2 (a
HgOH+1
Hg(OH)3-l
HgS2-2
Hg(HS)2 (aq
HgS04 (aq)
HgCH3NH2+2
Hg(CH3NH2)2
CR+3
CR(OH)+2
CR(OH)3 AQ
CR(OH)4-
CR02-
CRBR+2
CRCL+2
CRCL2 +
CROHCL2 AQ
CRF+2
CRI+2
CR(NH3)6+3
CRNH3)50H+2
CCRNH3)40H2
TCRNH3)40H2
CRNH3)6CL+2
CRNH3)6BR+2
CRNH3)6I +2
CRN03 +2
CRH2P04 +2
CRS04 +
CROHS04 AQ
CR20H2S04)S
CR20H2S04+2
CR20H2S042
0.0000
0.0000
-44.5220
-47.9430
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
-87.3400
-20.1400
0.0000
0.0000
0.0000
0.0000
-11.2110
-13.8470
-9.3740
0.0000
-16.7890
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
-15.6400
0.0000
-12.6200
0.0000
0.0000
0.0000
0.0000
8.0848
18.8949
30.1081
33.7935
35.7858
5.6139
5.0341
-3.2493
-11.7307
6.4503
4.7791
2.6974
-15.0042
31.2398
43.8178
7.4911
29.3846
53.2132
9.6200
5.6200
-7.1300
-18.1500
-17.7456
7.5519
9.3683
8.6580
2.9627
14.5424
4.8289
-32.5709
-30.2759
-29.8574
-30.5537
-31.7932
-31.8870
-32.0080
8.2094
31.9068
10.9654
8.2754
14.5278
16.1550
17.9288
219.5884
327.4945
454.3990
581.3035
708.2080
217.6204
234.6508
251.6812
268.7116
262.5949
324.5998
217.5973
251.6119
264.7100
266.7258
296.6476
231.6472
262.7044
51.9960
69.0033
103.0179
20.0252
83.9948
131.9000
87.4490
122.9020
139.9093
70.9944
178.9005
154.1784
154.1553
154.1322
154.1322
189.6314
234.0824
281.0829
114.0009
148.9832
148.0536
165.0609
330.1218
234.0642
330.1218
79
-------
Species
ID Number
2123300
2123301
2123302
2121800
2125800
2125801
2127320
5002120
4102120
3301431
3301441
3301442
3301451
3301452
3301461
3301462
3301471
3301472
3301481
3301482
1601431
1601441
1601451
1601452
1601471
1601472
1601481
6001431
6001441
6001451
6001452
1001431
1001441
1001451
1001461
1001471
1001481
201431
201432
201451
201452
2111431
2111432
2111451
Name
*****************
HCR04 -
H2CR04 AQ
CR207 -2
CR03CL -
CR03H2P04-
CR03HP04-2
CR03S04-2
NACR04-
KCR04-
KH ACETATE
KH TARTRAT
KH TARTRAT
KH GLYCINE
KH GLYCINE
KH SALICYL
KH SALICYL
KH GLUTAMA
KH GLUTAMA
KH PHTHALA
KH PHTHALA
KCD ACETATE
KCD TARTRAT
KCD GLYCINE
KCD GLYCINE
KCD GLUTAMA
KCD GLUTAMA
KCD PHTHALA
KPB ACETATE
KPB TARTRAT
KPB GLYCINE
KPB GLYCINE
KBA ACETATE
KB A TARTRATE
KBA GLYCINE
KBA SALICYL
KBA GLUTAMA
KBA PHTHALA
KAG ACETATE
KAG ACETATE
KAG GLYCINE
KAG GLYCINE
KCR ACETATE
KCR ACETATE
KCR GLYCINE
Standard
Enthalpy
Reaction
Aqueous
0.9000
0.0000
-2.9950
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
of
Log K
Grain Formula
Weight
Complexes **************
6.5089
5.6513
14.5571
7.3086
29.3634
26.6806
8.9937
0.6963
0.7990
4.7600
4.1600
2.5200
9.7800
2.3500
13.4000
3.0000
9.9500
4.2800
5.4000
3.1400
1.7000
3.9000
4.8000
4.0300
4.7800
2.7800
2.5000
2.1000
3.7800
5.4700
3.3900
0.4100
2.5400
0.7700
0.2100
1.2800
2.3300
0.7300
-0.0900
3.5100
3.3800
1.8000
2.9200
8.4000
117.0015
118.0094
215.9878
135.4472
196.9814
195.9735
196.0518
138.9834
155.0919
60.0600
149.1000
150.1100
75.0800
76.0900
137.1300
138.1400
146.1400
147.1500
165.1400
166.1500
171.4600
260.5000
186.4800
260.5500
257.5400
402.6700
276.5400
266.2600
355.3000
281.2800
355.3500
196.4100
285.4500
211.4300
273.4800
282.4900
301.4900
166.9300
225.9800
181.9500
256.0200
111.0600
170.1100
126.0800
80
-------
Species
ID Number
2111452
2111453
2111481
2111482
2111483
8711441
3601451
3601452
2089100
2089101
3089100
3089101
8089100
4289100
4289101
7089100
7015000
2089300
2089301
2089302
2089303
5089300
7089300
7089301
7050000
7041000
7049000
7046000
7015001
7080000
7010000
7028000
7023100
7060000
8015000
5189300
5189301
5189302
Name
*****************
KCR GLYCINE
KCR GLYCINE
KCR PHTHALA
KCR PHTHALA
KCR PHTHALA
KT1 TARTRAT
KHg GLYCINE
KHg GLYCINE
***************
URANINITE
U02 (AM)
U409 (C)
U308 (C)
USI04 (C)
UF4 (C)
UF4.2.5H20
UHP04)2,4H20
NINGYOITE
U03 (C)
GUMMITE
B-U02(OH)2
SCHOEPITE
RUTHERFORDIN
(U02)3(P04)2
H-AUTUNITE
NA-AUTUNITE
K-AUTUNITE
URAMPHITE
SALEEITE
AUTUNITE
SR-AUTUNITE
URANOCIRCITE
BASSETITE
TORBERNITE
PRZHEVALSKIT
URANOPHANE
U02N03)2
U02N03.2H20
U02N03.3H20
Standard
Enthalpy of
Reaction
Gram Formula
Log K Weight
Aqueous Complexes **************
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
Solid Species
18.6300
26.2300
101.2350
116.0200
14.5480
18.9000
0.5880
-3.8400
2.2700
19.3150
23.0150
13.7300
12.0450
1.4400
-94.9000
3.6000
0.4600
-5.8600
-9.7000
20.1800
14.3400
13.0500
10.1000
19.9000
15.9000
11.0000
0.0000
20.1400
6.0600
2.4050
6.4000
5.7000
5.5200
4.8000
2.4800
1.3900
10.8000
20.0000
**************
4.7000
-0.9340
3.3840
-21.1070
7.6200
18.6060
27.5700
51.5840
53.9060
-7.7190
-10.4030
-5.5440
-5.4040
14.4390
49.0370
47.9310
47.4090
48.2440
51.7490
43.6460
43.9270
44.4570
44.6310
44.4850
45.2790
44.3650
-17.4900
-12.3690
-4.8510
-3.6420
200.1500
274.2200
216.1400
380.2700
544.4000
352.4800
274.6800
348.7500
270.0278
270.0278
1096.1106
842.0822
330.1121
314.0226
359.0606
502.0486
504.0822
286.0272
286.0272
304.0424
322.0576
330.0370
1000.0262
732.0144
775.9780
808.2024
766.0756
754.3104
770.0784
817.6184
867.3384
785.8454
793.5444
937.1883
766.5176
394.0380
430.0690
448.0840
81
-------
Species
ID Number
5189303
2003000
6003000
6003001
6041000
6041001
6015000
5015000
5046000
4210000
6010000
2003001
2046000
5015001
6080000
2077000
8646000
8246000
2077001
2003002
8215000
5015002
6046000
8646003
2028100
2028101
4128100
1028000
6028100
7015002
4215000
8046000
2003003
2028102
8628000
1028001
6015001
4150000
3028100
5015003
5046001
6050000
6041002
6028101
Name
***************
U02N03.6H20
ALOH3(A)
ALOHS04
AL4(OH)10S04
ALUM K
ALUNITE
ANHYDRITE
ARAGONITE
ARTINITE
BAF2
BARITE
BOEHMITE
BRUCITE
CALCITE
CELESTITE
CHALCEDONY
CHRYSOTILE
CLINOENSTITE
CRISTOBALITE
DIASPORE
DIOPSIDE
DOLOMITE
EPSOMITE
SEPIOLITE(C)
FERRIHYDRITE
FE3(OH)8
FEOH)2.7CL.3
FES PPT
FE2(S04)3
FC03APATITE
FLUORITE
FORSTERITE
GIBBSITE (C)
GOETHITE
GREENALITE
GREIGITE
GYPSUM
HALITE
HEMATITE
HUNTITE
HYDRMAGNESIT
JAROSITE NA
JAROSITE K
" JAROSITE H
Standard
Enthalpy of
Reaction
Solid Species
-4.7700
27.0450
0.0000
0.0000
-7.2200
-3.9180
3.7690
2.6150
28.7420
-1.0000
-6.2800
28.1300
25.8400
2.5850
0.4700
-4.6150
52.4850
20.0150
-5.5000
24.6300
32.2800
8.2900
-2.8200
27.2680
0.0000
0.0000
0.0000
0.0000
59.1200
-39.3900
-4.7100
48.5100
22.8000
14.4800
0.0000
0.0000
-0.2610
-0.9180
30.8450
25.7600
52.2100
36.1800
31.2800
55.1500
Log K
**************
-2.3000
-10.3800
3.2300
-22.7000
5.1700
1.3460
4.6370
8.3600
-9.6000
5.7600
9.9760
-8.5780
-16.7920
8.4750
6.4650
3.5230
-32.1880
-11.3380
3.5870
-6.8730
-19.8860
17.0000
2.1400
-15.9130
-4.8910
-20.2220
3.0400
3.9150
-3.5800
114.4000
10.9600
-28.2980
-8.7700
-0.5000
-20.8100
45.0350
4.8480
-1.5820
4.0080
29.9680
8.7660
11.2000
14.8000
12.1000
Gram Formula
Weight
502.1300
78.0073
140.0505
374.0616
438.3597
414.2141
136.1416
100.0894
196.6941
175.3368
233.4016
59.9884
58.3268
100.0894
183.6816
60.0848
277.1349
100.3964
60.0848
59.9884
216.5608
184.4108
246.4807
323.9313
104.8692
297.6002
110.4029
85.9110
395.8788
967.3670
78.0768
236.8234
78.0037
86.8536
365.7393
289.7970
172.1722
58.4428
155.6919
353.0536
467.6736
478.6978
494.8100
480.7320
82
-------
Species
ID Number
1028002
8450000
3028101
5046002
3028000
6028000
6050001
3050000
5046003
8646001
1028003
2077002
8646004
5028000
2077003
2077004
4280000
7028100
5080000
8646002
6050002
5050001
8215001
7028001
5010000
2047000
2047001
2047002
3047100
3047000
2047003
2047100
5047000
4147000
1047000
6047000
6047100
7047000
3041000
3010000
3015000
3044000
3015001
23000
Name
A**************
MACKINAWITE
MAGADIITE
MAGHEMITE
MAGNESITE
MAGNETITE
MELANTERITE
MIRABILITE
NATRON
NESQUEHONITE
PHLOGOPITE
PYRITE
QUARTZ
SEPIOHTE(A)
SIDERITE
SI02(A,GL)
SI02(A,PT)
SRF2
STRENGITE
STRONTIANITE
TALC
THENARDITE
THERMONATR
TREMOLITE
VIVIANITE
WITHERITE
PYROLUSITE
BIRNESSITE
NSUTITE
BIXBYITE
HAUSMANNITE
PYROCROITE
MANGANITE
RHODOCHROSIT
MNCL2, 4H20
MNS GREEN
MNS04
MN2(S04)3
MN3(P04)2
A-CRYPTOMELN
HOLLANDITE
TODOROKITE
LITHIOPHORIT
RANCIEITE
CU METAL
Standard
Enthalpy of
Reaction
Solid Species
0.0000
0.0000
0.0000
6.1690
50.4600
-2.8600
-18.9870
-15.7450
5.7890
86.3600
-11.3000
-6,2200
0.0000
5.3280
-4.4400
-3.9100
-1.2500
2.0300
0.6900
35.0050
0.5720
2.8020
96.6150
0.0000
-0.3600
29.1800
0.0000
0.0000
15.2450
80.1400
22.5900
0.0000
2.0790
-17.3800
5.7900
15.4800
39.0600
-2.1200
0.0000
0.0000
0.0000
0.0000
0.0000
-17.1300
Log K
**************
4.6480
14.3000
-6.3860
8.0290
-3.7370
2.4700
1.1140
1.3110
5.6210
-66.3000
18.4790
4.0060
-18.7800
10.5500
3.0180
2.7100
8.5400
26.4000
9.2500
-23.0550
0.1790
-0.1250
-56.5460
36.0000
8.5850
-15.8610
-18.0910
-17.5040
0.6110
-61.5400
-15.0880
0.2380
10.4100
-2.7100
-3.8000
-2.6690
5.7110
23.8270
0.0000
0.0000
0.0000
0.0000
0.0000
8.7600
Gram Formula
Weight
87.9110
532.6521
159.6922
84.3214
231.5386
278.0157
322.1942
286.1420
138.3673
417.2863
119.9750
60.0848
323.9308
115.8564
60.0848
60.0848
125.6168
186.8490
147.6294
379.2888
142.0412
124.0043
812.4096
501.6062
197.3494
86.9368
86.9368
86.9368
157.8742
228.8116
88.9528
87.9448
114.9474
197.9052
87.0020
150.9996
398.0608
354.7568
775.7382
817.4214
592.4641
1953.3934
466.1930
63.5460
83
-------
Species
D Number Name
Standard
Enthalpy of
Reaction Log K
Gram Formula
Weight
*************** Solid Species **************
4123000 NANTOKITE
4223000 CUF
2023000 CUPRITE
1023000 CHALCOCITE
1023001 DJURLEITE
1023002 ANILITE
1023003 BLAUBLEI II
1023100 BLAUBLEI I
1023101 COVELLITE
6023000 CU2S04
3023000 CUPROUSFERIT
4123100 MELANOTHALLI
5023100 CUC03
4223100 CUF2
4223101 CUF2, 2H20
2023100 CU(OH)2
4123101 ATACAMITE
5123100 CU2(OH)3N03
6023100 ANTLERITE
6023101 BROCHANTITE
6023102 LANGITE
2023101 TENORITE
6023103 CUOCUS04
7023100 CU3(P04)2
7023101 CU3(P04)2,3W
6023104 CUS04
6023105 CHALCANTHITE
2023102 DIOPTASE
3023100 CUPRICFERIT
1023102 CHALCOPYRITE
4023000 CUBR
4323000 GUI
95000 ZN METAL
4195000 ZNCL2
5095000 SMITHSONITE
5095001 ZNC03, 1H20
4295000 ZNF2
2095000 ZN(OH)2 (A)
2095001 ZN(OH)2 (C)
2095002 ZN(OH)2 (B)
2095003 ZN(OH)2 (G)
2095004 ZN(OH)2 (E)
4195001 ZN2(OH)3CL
4195002 ZN5(OH)8CL2
-9.9800
12.3700
-6.2450
-49.3500
-47.8810
-43.5350
0.0000
0.0000
-24.0100
4.5600
3.8000
12.3200
0.0000
13.3200
3.6500
15.2500
18.6900
17.3500
0.0000
0.0000
39.6100
15.2400
35.5750
0.0000
0.0000
18.1400
-1.4400
8.9600
38.6900
-35.4800
-13.0800
-20.1400
36.7800
17.4800
4.3600
0.0000
13.0800
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
6.7600
-7.0800
1.5500
34.6190
33.9200
31.8780
27.2790
24.1620
23.0380
1.9500
8.9200
-3.7300
9.6300
0.6200
4.5500
-8.6400
-7.3400
-9.2400
-8.2900
-15.3400
-16.7900
-7.6200
-11.5300
36.8500
35.1200
-3.0100
2.6400
-6.5000
-5.8800
35.2700
8'. 2 100
11.8900
-25.7570
-7.0300
10.0000
10.2600
1.5200
-12.4500
-12.2000
-11.7500
-11.7100
-11.5000
-15.2000
-38.5000
98.9990
82.5444
143.0914
159.1560
154.9620
143.2695
121.0284
101.9646
95.6100
223.1536
151.3918
134.4520
123.5552
101.5428
137.5732
97.5606
213.5669
240.1188
354.7248
452.2854
470.3006
79.5454
239.1490
380.5808
434.6264
159.6036
249.6796
157.6449
239.2376
183.5130
143.4500
190.4505
65.3800
136.2860
125.3892
143.4044
103.3768
99.3946
99.3946
99.3946
99.3946
99.3946
217.2349
533.8644
84
-------
Species
ID Number
6095000
6095001
5195000
2095005
2095006
6095002
7095000
1095000
1095001
1095002
8295000
8095000
6095003
6095004
6095005
6095006
4095000
4395000
16000
16001
5016000
4116000
4116001
4116002
4216000
2016000
2016001
4116003
6016000
6016001
6016002
2016002
7016000
8216000
6016003
6016004
6016005
1016000
4016000
4316000
60000
4160000
4160001
4160002
Name
***************
ZN2(OH)2S04
ZN4(OH)6S04
ZNN03)2,6H20
ZNO( ACTIVE)
Z INCITE
ZN30(S04)2
ZN3(P04),4W
ZNS (A)
SPHALERITE
WURTZITE
ZNSI03
WILLEMITE
ZINCOSITE
ZNS04, 1H20
BIANCHITE
GOSLARITE
ZNBR2, 2H20
ZNI2
CD METAL
GAMMA CD
OTAVITE
CDCL2
CDCL2, 1H20
CDCL2,2.5H20
CDF 2
CD(OH)2 (A)
CD(OH)2 (C)
CDOHCL
CD3(OH)4S04
CD30H2(S04)2
CD4(OH)6S04
MONTEPONITE
CD3(P04)2
CDSI03
CDS04
CDS04, 1H20
CDS04,2.7H20
GREENOCKITE
CDBR2, 4H20
CD 12
PB METAL
COTUNNITE
MATLOCKITE
PHOSGENITE
Standard
Enthalpy of
Reaction
Solid Species
0.0000
0.0000
-5.5100
0.0000
21.8600
62.0000
0.0000
-3.6700
-8.2500
-5.0600
18.2700
33.3700
19.2000
10.6400
0.1600
-3.3000
7.5100
13.4400
18.0000
18.1400
0.5800
4.4700
1.8200
-1.7100
9.7200
20.7700
0.0000
7.4070
0.0000
0.0000
0.0000
24.7600
0.0000
16.6300
14.7400
7.5200
4.3000
-16.3600
-7.2300
-4.0800
-0.4000
-5.6000
-7.9500
0.0000
Log K
**************
-7.5000
-28.4000
-3.4400
-11.3100
-11.1400
-19.0200
32.0400
9.0520
11.6180
9.6820
-2.9300
-15.3300
-3.0100
0.5700
1.7650
1.9600
-5.2100
-7.2300
-13.4900
-13.5900
13.7400
0.6800
1.7100
1.9400
2.9800
-13.7300
-13.6500
-3.5200
-22.5600
-6.7100
-28.4000
-15.1200
32.6000
-9.0600
0.1000
1.6570
1.8730
15.9300
2.4200
3.6100
-4.2700
4.7700
9.4300
19.8100
Gram Formula
Weight
260.8322
459.6214
297.4810
81.3794
81.3794
404.2546
458.1436
97.4400
97.4400
97.4400
141.4637
220.8431
161.4376
179.4528
269.5288
287.5440
261.2184
319.1890
112.4100
112.4100
172.4192
183.3160
201.3312
228.3536
150.4068
146.4246
146.4246
164.8703
501.3168
563.3598
647.7414
128.4094
527.1728
188.4937
208.4676
226.4828
256.3879
144.4700
344.2788
366.2190
207.2000
278.1060
261.6514
545.3152
85
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
*************** Solid Species **************
5060000 CERRUSITE
4260000 PBF2
2060000 MASSICOT
2060001 LITHARGE
2060002 PBO, .3H20
5060001 PB20C03
6060000 LARNAKITE
6060001 PB302S04
6060002 PB403S04
7060001 CLPYROMORPH
7060002 HXYPYROMORPH
2095002 ZN(OH)2 (B)
2095003 ZN(OH)2 (G)
2095004 ZN(OH)2 (E)
4195001 ZN2(OH)3CL
4195002 ZN5(OH)8CL2
6095000 ZN2(OH)2S04
6095001 ZN4(OH)6S04
5195000 ZNN03)2,6H20
2095005 ZNO(ACTIVE)
2095006 ZINCITE
6095002 ZN30(S04)2
7095000 ZN3(P04),4W
1095000 ZNS (A)
1095001 SPHALERITE
1095002 WURTZITE
8295000 ZNSI03
8095000 WILLEMITE
6095003 ZINCOSITE
6095004 ZNS04, 1H20
6095005 BIANCHITE
6095006 GOSLARITE
4095000 ZNBR2, 2H20
4395000 ZNI2
16000 CD METAL
16001 GAMMA CD
5016000 OTAVITE
4116000 CDCL2
4116001 CDCL2, 1H20
4116002 CDCL2,2.5H20
4216000 CDF2
2016000 CD(OH)2 (A)
2016001 CD(OH)2 (C)
4116003 "CDOHCL
-4.8600
0.7000
16.7800
16.3800
0.0000
11.4600
6.4400
20.7500
35.0700
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
-5.5100
0.0000
21.8600
62.0000
0.0000
-3.6700
-8.2500
-5.0600
18.2700
33.3700
19.2000
10.6400
0.1600
-3.3000
7.5100
13.4400
18.0000
18.1400
0.5800
4.4700
1.8200
-1.7100
9.7200
20.7700
0.0000
7.4070
13.1300
7.4400
-12.9100
-12.7200
-12.9800
0.5000
0.2800
-10.4000
-22.1000
84.4300
62.7900
-11.7500
-11.7100
-11.5000
-15.2000
-38.5000
-7.5000
-28.4000
-3.4400
-11.3100
-11.1400
-19.0200
32.0400
9.0520
11.6180
9.6820
-2.9300
-15.3300
-3.0100
0.5700
1.7650
1.9600
-5.2100
-7.2300
-13.4900
-13.5900
13.7400
0.6800
1.7100
1.9400
2.9800
-13.7300
-13.6500
-3.5200
267.2092
245.1968
223.1994
223.1994
229.1444
490.4086
526.4570
749.6564
972.8558
1356.3672
1337.9215
99.3946
99.3946
99.3946
217.2349
533.8644
260.8322
459.6214
297.4810
81.3794
81.3794
404.2546
458.1436
97.4400
97.4400
97.4400
141.4637
220.8431
161.4376
179.4528
269.5288
287.5440
261.2184
319.1890
112.4100
112.4100
172.4192
183.3160
201.3312
228.3536
150.4068
146.4246
146.4246
164.8703
86
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
*************** Solid Species **************
6016000
6016001
6016002
2016002
7016000
8216000
6016003
6016004
6016005
1016000
4016000
4316000
60000
4160000
4160001
4160002
5060000
4260000
2060000
5023102
3006000
3006001
4306000
1006000
1006001
3006100
5295000
5216000
5260000
7047001
7060006
7060007
73100
7203000
7215000
7223100
7228100
7247000
7254000
7260000
7295000
7210000
90000
2090000
CD3(OH)4S04
CD30H2(S04)2
CD4(OH)6S04
MONTEPONITE
CD3(P04)2
CDSI03
CDS04
CDS04, 1H20
CDS04.2.7H20
GREENOCKITE
CDBR2, 4H20
CD 12
PB METAL
COTUNNITE
MATLOCKITE
PHOSGENITE
CERRUSITE
PBF2
MASSICOT
AZURITE
ARSENOLITE
CLAUDETITE
AS 13
ORPIMENT
REALGAR
AS205
ZN(B02)2
CD(B02)2
PB(B02)2
MNHP04(C)
PBHP04
PB3(P04)2
SULFUR
ALAS04.2W
CA3 (AS04 ) 2 6W
CU3(AS04)26W
FEAS04.2W
MN3AS0428W
NI3(AS04)28W
PB3(AS04)2
ZN3AS0422.5W
BA3(AS04)2
V METAL
VO
7.
4.
0.0000
0.0000
0.0000
24.7600
0.0000
16.6300
14.7400
5200
3000
16.3600
-7.2300
-4.0800
-0.4000
-5.6000
-7.9500
0.0000
-4.8600
0.7000
16.7800
23.7700
•14.3300
13.2900
-1.8750
82.8900
•30.5450
5.4050
0.0000
0.0000
5.8000
0.0000
0.0000
0.0000
4.2000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
-2.6400
62.9000
28.0200
-22.5600
-6.7100
-28.4000
-15.1200
32.6000
-9.0600
0.1000
1.6570
1.8730
15.9300
2.4200
3.6100
-4.2700
4.7700
9.4300
19.8100
13.1300
7.4400
-12.9100
16.9200
2.8010
3.0650
-4.1550
60.9710
19.7470
-6.6990
-8.2900
-9.8400
-7.6100
25.4000
23.9000
44.5000
2.1100
-4.8000
-22.3000
-6.1000
-0.4000
-12.5000
-15.7000
-5.8000
-13.6500
8.9100
-42.3500
-13.0800
501.3168
563.3598
647.7414
128.4094
527.1728
188.4937
208.4676
226.4828
256.3879
144.4700
344.2788
366.2190
207.2000
278.1060
261.6514
545.3152
267.2092
245.1968
223.1994
344.6716
395.6824
395.6824
455.6347
246.0350
106.9855
229.8400
150.9893
198.0188
292.8093
150.9174
303.1693
811.5125
32.0640
165.9006
506.1700
576.5680
230.7967
586.7746
459.1707
899.4079
518.9862
689.8580
50.9400
66.9390
87
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
*************** Solid Species **************
4190000
3090100
2090100
4190100
4190101
3090200
2090200
4290200
6090200
7090200
4190200
3090300
7315000
7315001
7315002
7315003
7328000
7346000
7346001
7347000
7349000
7350000
7350001
7350002
7360000
7360001
7346002
7302000
7302001
7302002
4190300
3090101
3090201
3090202
2015000
2015001
2028000
2046001
3028001
3046000
3046001
4250000
8215002
8215003
VCL2
V203
V(OH)3
VCL3
VOCL
V204
VO(OH)2
VF4
VOS04 (C)
(VO)3(P04)2
VOCL2
V205
TYUYAMUN1TE
CA-VAN ABATE
CA3(V04)2
CA2V207
FE-VANADATE
MG-VANADATE
MG2V207
MN-VANADATE
NH4V03
NA-VAN ABATE
NA3V04
NA4V207
PB3(V04)2
PB2V207
CARNOTITE
AG-VANABATE
AG2HV04
AG3H2V05
V02CL
V305
V407
V6013
LIME
PORTLANBITE
WUSTITE
PERICLASE
HERCYNITE
SPINEL
MAG-FERRITE
CRYOLITE
WOLLASTONITE
P-WOLLSTANIT
35.8000
19.7200
0.0000
43.9600
26.1700
14.0700
0.0000
47.5900
20.7200
0.0000
28.2000
4.1600
18.3000
10.1300
35.0700
19.0600
7.3700
16.3300
30.5000
11.0500
3.7700
7.0100
44.4200
24.0300
8.6800
3.2200
8.7000
0.0000
0.0000
0.0000
9.6500
23.5300
39.1500
-64.8900
46.2650
30.6900
24.8460
36.1350
78.3600
89.0890
66.6390
-10.9040
19.4980
21.0680
-17.9700
-4.9000
-7.6500
-21.7300
-9.4100
-4.2700
-5.8500
-14.9300
-3.5700
8.3700
-12.7900
0.7200
-2.0400
-2.8300
-19.4800
-8.7500
1.8600
-5.6400
-13.1800
-2.4500
-2.6900
-3.7100
-36.9400
-18.7000
-3.0700
0.9500
-0.2300
-0.7700
-1.4800
-5.1800
-2.8100
-1.8700
-7.1400
60.8600
-32.7970
-22.6750
-11.6870
-21.5100
-27.1620
-36.3330
-16.7650
31.4900
-12.9960
-13.8460
121.8460
149.8780
101.9620
157.2990
137.8450
165.8780
100.9540
126.9320
162.9970
390.7530
137.8450
181.8770
810.0130
237.9560
350.1150
294.0360
508.4310
222.1860
262.4960
252.8160
116.9770
121.9280
183.9080
305.8360
851.4750
628.2760
848.1330
206.8080
331.6860
456.5630
118.3920
232.8170
315.7560
513.6320
56.0800
73.0880
71.8500
40.3200
173.8100
142.2800
200.0200
209.9530
116.1700
116.1700
88
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
*************** Solid Species **************
8015001
8015002
8015007
8015003
8015005
8015004
8441000
8441001
8441002
8441003
8450004
8015006
3028102
8650000
8641002
8615000
8646005
87000
2087000
2087001
4187000
4087000
4387000
1087000
6087000
1187000
6187000
5187000
5087000
2087101
2087100
76000
76001
1228001
1260000
1202000
1216000
1223100
1223000
1223101
1223001
1228000
1247000
1295000
CA-OLIVINE
LARNITE
CA3SI05
MONTICELLITE
AKERMINITE
MERWINITE
KALSILITE
LEUCITE
MICROCLINE
H SANIDINE
NEPHELINE
GEHLENITE
LEPIDOCROCIT
NA-NONTRONIT
K-NONTRONITE
CA-NONTRONIT
MG-NONTRONIT
Tl metal
T120
T10H
T1C1
TlBr
Til
T12S
T12S04
T12Se
T12Se04
T1N03
T12C03
T1(OH)3
Avi cenni te
Se hex,blac
Se (A)
Ferroselite
Clausthalit
Ag2Se
CdSe
CuSe
Cu2Se alpha
CuSe2
Cu3Se2
FeSe
MnSe
ZnSe
54.6950
57.2380
106.3350
49.4210
76.4450
107.1110
28.9190
22.0850
12.3090
14.2520
33.2040
116.1250
0.0000
0.0000
0.0000
0.0000
0.0000
-1.2800
23.0550
9.9350
-10.1370
-13.6410
-17.2810
-21.5600
-7.9400
-20.3600
-9.7600
-10.0200
-8.0200
0.0000
0.0000
-3.8000
-2.6000
-11.3000
-28.0000
-64.9500
-18.1600
-28.9500
-51.2100
-33.6000
-81.3400
-0.5000
13.4600
-6.4390
-37.6490
-39.1410
-73.8670
-30.2720
-47.4720
-68.5430
-12.8380
-6.4230
-0.6160
-1.0620
-14.2180
-56.8220
-1.3710
14.5040
15.5490
20.8890
20.5890
-5.6733
-27.0984
-12.9225
3.7243
5.4190
7.1964
7.1832
3.6942
6.6848
4.0168
1.5319
3.8482
6.4503
16.3236
7.6963
7.1099
18.5959
21.2162
43.6448
18.0739
26.5121
36.0922
33.3655
63.4911
7.1466
-5.3508
11.3642
172.2500
172.2500
228.3300
156.4900
272.6600
328.7400
158.1700
218.2600
378.3500
378.3500
142.0610
374.2100
72.8600
425.2690
430.5850
424.3750
480.6150
204.3700
424.7394
221.3773
239.8230
284.2740
331.2745
440.8000
504.7976
487.7000
551.6976
266.3749
468.7492
255.3919
456.7382
78.9600
78.9600
213.7670
286.1600
294.6960
191.3700
142.5060
206.0520
221.4660
348.5580
134.8070
133.8980
144.3400
89
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
*************** Solid Species **************
1220000
1254000
2076100
6110000
6115000
6123100
6128100
6128101
6146000
6147001
6154000
6180000
6147000
6120000
6102000
2076200
6102001
6110001
6115001
6160000
6180001
36000
4036000
5036000
4136000
4236000
4336000
2036000
7036000
6036000
6136000
4036100
5036100
4136100
4336100
2036100
2036101
1036100
1036101
6036100
6136100
4336102
4336103
2021100
CoSe
NiSe
Se02
BaSe03
CaSe03:2H20
CuSe03:2H20
Fe2(Se03)3:
Fe2(OH)4SeO
MgSe03:6H20
MnSE03:2H20
NiSe03:2H20
SrSe03
MnSe03
CoSe03
Ag2Se03
Se03
Ag2Se04
BaSe04
CaSe04:2H20
PbSe04
SrSe04
Hg metal (1
Hg2Rr2
Hg2C03
Ca 1 ome 1
Hg2F2
Hg2I2
Hg2(OH)2
Hg2HP04
Hg2S04
Hg2Se03
HgBr2
HgC03
HgC12
Coccinite
Montroydite
Hg(OH)2
Cinnabar
Metacinnaba
HgS04
HgSe03
Hgl2:2NH3
HgI2:6NH3
" CR(OH)2
0.0000
0.0000
-0.3350
6.2800
4.6500
8.8100
0.0000
0.0000
-1.2500
-2.0300
7.4100
0.0000
0.0000
0.0000
-9.4700
34.9850
-10.4500
-2.0000
-0.8800
-3.8000
-2.6900
-19.9350
-31.2520
0.0000
-23.4440
4.4320
0.0000
0.0000
0.0000
-0.2300
0.0000
-34.4520
-22.1300
-27.2640
-49.7320
-5.1150
0.0000
-60.4300
-59.5300
-3.5100
0.0000
-32.6320
20.5680
8.5100
16.2723
17.7382
-0.1246
-4.1634
-2.8139
-0.4838
20.6262
-1.5539
-4.0314
-0.9822
-2.8147
-0.1034
-0.0440
-0.1906
8.1977
-21.0440
8.9014
5.1895
2.9473
6.8387
6.8747
13.4552
22.2091
13.9586
17.8427
3.0811
28.2782
-5.2603
25.9795
6.1593
6.9290
25.3730
28.6817
21.7858
34.6599
3.6503
3.4963
45.1885
44.8220
9.4189
12.6953
16.1066
-33.8566
-10.8189
137.8932
137.6600
110.9588
264.2882
203.0686
226.5346
528.5990
306.6814
259.3544
217.9266
221.6886
214.5782
181.8962
185.8914
342.6942
126.9582
358.6936
280.2876
219.0680
350.1576
230.5776
200.5900
560.9880
461.1892
472.0860
439.1768
654.9890
435.1946
497.1593
497.2376
528.1382
360.3980
260.5992
271.4960
454.3990
216.5894
234.6046
232.6500
232.6500
296.6476
327.5482
488.4598
556.5814
86.0106
90
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
*************** Solid Species
**************
4021100
4121100
4221100
4321100
3021100
3021101
21000
3021102
2021102
2021101
4121000
3021200
3021201
3021202
3021203
3021204
3021205
3021206
3021207
3021208
3021209
3021210
3021211
3021212
3021213
3021214
2021200
3015000
3036000
3087000
CRBR3
CRCL3
CRF3
CRI3
FECR204
MGCR204
CR METAL
CR203
CR(OH)3 (A)
CR(OH)3 (C)
CRCL2
AG2CR04
BACR04
CS2CR04
CS2CR207
CUCR04
K2CR04
K2CR207
LI2CR04
MGCR04
(NH4)2CR04
NA2CR04
NA2CR207
PBCR04
RB2CR04
SRCR04
Cr03
CaCr04
Hg2Cr04
T12Cr04
33.7770
27.5090
4.3630
32.1270
24.8600
39.8600
34.3000
12.1250
0.0000
7.1150
19.6660
-14.0400
-6.3900
-7.5040
-22.8990
0.0000
-4.2500
-18.1250
10.8220
21.2600
-2.1900
4.6100
-5.3050
-10.2300
-5.8920
2.4200
1.2450
6.4400
0.0000
25.3100
-19.9086
-13.5067
13.2597
-20.4767
0.9016
-12.0796
-32.2440
3.3937
0.7500
-1.7005
-15.8676
11.5548
9.6681
0.5541
17.7793
5.4754
-0.0073
15.6712
-4.8568
-5.3801
-0.4046
-3.2618
9.8953
13.6848
0.0968
4.8443
3.2105
2.2657
8.7031
12.0136
291.7080
158.3550
108.9912
432.7095
223.8366
192.2946
51.9960
151.9902
103.0179
103.0179
122.9020
331.7296
253.3236
381.8044
481.7986
179.5396
194.1902
294.1844
129.8756
140.2986
152.0702
161.9731
261.9673
323.1936
286.9292
203.6136
99.9942
156.0736
517.1736
524.7336
************** Redox Couples ****************
2812800
4914920
4904920
600610
8908930
8918930
8928930
4714700
2302310
FE+3/FE+2
N02/N03
NH4/N03
AS03/AS04
U+3/U02+2
U+4/U02+2
U02+/U02+2
MN+3/MN+2
' CU+l/CU+2
-10.0000
-43.7600
-187.0550
-30.0150
-10.0300
-34.4300
-3.3000
25.7600
1.6500
13.0320
28.5700
119.0770
19.4440
0.4200
9.2160
2.7850
-25.5070
2.7200
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
91
-------
Species
ID Number
Name
Standard
Enthalpy of
Reaction
Log K
Gram Formula
Weight
*************** Redox Couples **************
9009030
9019030
9029030
7307320
8718700
7617600
7627600
7627610
3613600
2102110
2122110
V+2/V02+1
V+3/V02+1
VO+2/V02+1
HS-/S04-2
T1(OH)3/T1+
HSe03-l/HSe
Se04-2/HSe-
Se04/HSe03
Hg(OH)2/Hg2
CR+2/CROH)2
CR04/CROH)2
-35.3300
-44.2300
-29.3200
-60.1400
0.0000
-78.1700
-126.3000
-48.0950
-63.5900
-6.3600
-103.0000
3301404
3301403
3300021
3300022
8913305
3300023
3600001
3600002
3611400
3601300
3601800
3602700
3603800
3611300
3612700
3613800
******************** Qas phases
CH4(GAS)
C02(GAS)
02(AQ) SATO
02(AQ) CALC
KU6(OH)15+9
02(GAS)
Hg (g)
Hg2 (g)
Hg(CH3)2 (g
HgBr (g)
HgCl (g)
HgF (g)
Hgl (g)
HgBr2 (g)
HgF2 (g)
HgI2 (g)
-61.0000
-0.5300
0.0000
133.8300
0.0000
-34.1570
-5.2650
-13.8700
115.4000
34.0040
40.0980
60.9160
25.2640
-14.3500
0.0000
-28.6300
18.3800
22.6100
16.9300
33.6600
48.0178
44.8660
81.1850
36.3190
42.9870
-2.9470
67.3760
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
0.0000
*****************
40.1000
18.1600
-45.5400
-85.9800
-17.2290
-20.7800
7.8708
14.9630
73.7240
-16.7900
-20.5000
•32.7200
-11.1500
18.4700
-0.3800
27.2800
16.0432
41.0100
31.9988
31.9988
1683.2845
0.0000
200.5900
401.1800
230.6594
280.4940
236.0430
219.5884
327.4945
360.3980
238.5868
454.3990
92
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