U.S. ENVIRONMENTAL PROTECTION AGENCY
Office Of Air And Radiation
Office Of Air Quality Planning And Standards
Research Triangle Park, North Carolina 27711
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This report has been reviewed by the Office Of Air Quality Planning And Standards, U.S. Environmental
Protection Agency, and has been approved for publication as received from the Radian Corporation. Approval
does not signify that the contents necessarily reflect the views and policies of the Agency, neither does mention
of trade names or commercial products constitute endorsement or recommendation for use.
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CONTENTS
List of Figures
List of Tables ....!!.'.*!!!!.*!!!."!!!!!!!! lv
1. Purpose of Document j
2. Overview of Document Contents 3
3. Background. r
Nature of Pollutant !!!!!!!!!! 5
Overview of Production and Use 5
References for Section 3 ][ 14
4. Emissions from Acrylonitrile Production 15
Acrylonitrile Production. !!!!!.*! 15
References for Section 4 !!!!!!!! 24
5. Emissions from Industries Using Acrylonitrile as a
Feedstock 26
Acrylic and Modacrylic Fiber Production 26
Production of SAN and ABS Resins '. 34
Nitrile Rubber and Latex Production 46
Production of Adiponitrile [[[ 59
Production of Acrylamide 52
References for Section 5 55
6. Source Test Procedures 57
Literature Review of Sampling Methods ....!!! 57
Literature Review of Analytical Procedures 59
References for Section 6. 61
iii
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LIST OF FIGURES
Number Page
1 End use distribution of acrylonitrile 9
2 Basic operations and controls that may be used in
acrylonitrile production plants 16
3 Basic suspension and solution polymerization processes
used in the production of acrylic fibers 28
4 Acrylic fiber production via the suspension polymerization
process 29
5 SAN production processes: emulsion, mass and suspension
polymerization 37
6 ABS emulsion polymerization processes 40
7 ABS produced via mass polymerization 42
8 ABS produced via suspension polymerization 43
9 Hypothetical nitrile elastomer production process.. 47
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LIST OF TABLES
page
1 Physical and Chemical Properties of Acrylonitrile .......... 6
2 Acrylonitrile Monomer Production Sites ..................... 7
3 Estimated Consumption of Acrylonitrile by Product Type in
1979 ..... . ......................................... :: ..... : 10
4 Maj or Acrylonitrile Consumers .......... . ....... 4 ........... 1 1
5 Stream, Vent, and Discharge Codes for Figure 2 ............. 17
6 Uncontrolled and Controlled Acrylonitrile Emission Factors
for a Hypothetical Acrylonitrile Production Plant .......... 22
7 Domestic Acrylic Fiber Producers in 1983 ................... 35
8 Domestic ABS/SAN Resin Producers in 1983 ................... 45
9 Domestic Nitrile Elastomer Producers in 1983 ............... 51
10 'Domestic Acrylamide Producers in 1983 ......... .... ......... 53
11 Advantages and Disadvantages of Acrylonitrile Sampling and
Analysis Procedures ........ . ............................ . . . 53
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ACRYLONITRILE
SECTION 1
PURPOSE OF DOCUMENT
EPA, States, and local air pollution control agencies are becoming
increasingly aware of the presence of substances in the ambient air that may
be toxic at certain concentrations. This awareness, in turn, has led to
attempts to identify source/receptor relationships for these substances and
to develop control programs to regulate emissions. Unfortunately, very
little information is available on the ambient air concentrations of these
substances or on the sources that may be discharging them to the atmosphere.
To assist groups interested in inventorying air emissions of various
potentially toxic substances, EPA is preparing a series of documents such as
this that compiles available information on sources and emissions of these
substances. This document specifically deals with acrylonitrile. Its
intended audience includes Federal, State, and local air pollution personnel
and others who are interested in locating potential emitters of
acrylonitrile and making gross estimates of air emissions therefrom.
Because of the limited amounts of data available on acrylonitrile
emissions, and since the configuration of many sources will not be the same
as those described herein, this document,is best used as a primer to inform
air pollution personnel about (1) the types of sources that may emit
acrylonitrile, (2) process variations and release points that may be
expected within these sources, and (3) available emissions information
indicating the potential for acrylonitrile to be released into the air from
each operation.
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The rea'der is strongly cautioned against using the emissions
information contained in this document to try to develop an exact assessment
of emissions from any particular facility. Since insufficient data are
available to develop statistical estimates of the accuracy of these emission
factors, no estimate can be made of the error that could result when these
factors are used to calculate emissions for any given facility. It is
possible, in some extreme cases, that orders-of-magnitude differences could
result between actual and calculated emissions, depending on differences in
source configurations, control equipment and operating practices. Thus, in
situations where an accurate assessment of acrylonitrile emissions is
necessary, source-specific information should be obtained to confirm the
existence of particular emitting operations, the types and effectiveness of
control measures, and the impact of operating practices. A source test
and/or material balance should be considered as the best means to determine
air emissions directly from an operation.
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SECTION 2
OVERVIEW OF DOCUMENT CONTENTS
As noted in Section 1, the purpose of this document is to assist
Federal, State, and local air pollution agencies and others who are
interested in locating potential air emitters of acrylonitrile and making
gross estimates of air emissions therefrom. Because of the limited
background data available, the information summarized in this document does
not and should not be assumed to represent the source configuration or
emissions associated with any particular facility.
This section provides an overview of the contents of this document. It
briefly outlines the nature, extent and format of the material presented in
the remaining sections of this report.
Section 3 of this document provides a brief "summary of the physical and
chemical characteristics of acrylonitrile, its commonly occurring forms and
an overview of its production and uses. A table summarizes the quantities
of acrylonitrile consumed in various end uses in the United States. This
background section may be useful to someone who needs to develop a general
perspective on the nature of the substance and where it is manufactured and
consumed.
The fourth and fifth sections of this document focus on major
industrial source categories that may discharge acrylonitrile air emissions.
Section 4 discusses the production of acrylonitrile and Section 5 discusses
the use of acrylonitrile as an industrial feedstock in the productipn of
acrylic fibers, SAN/ABS resins, nitrile elastomers, acrylamide, and
adiponitrile. For each major industrial source category described in
Sections 4 and 5, example process descriptions and flow diagrams are given,
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potential emission points are identified, and available emission factor
estimates are presented that show the potential for acrylonitrile emissions
before and after controls employed by industry. Individual companies are
named that are reported to be involved with either the production and/or use
of acrylonitrile, based on industry contacts and available trade
publications.
The final section of this document summarizes available procedures for
source sampling and analysis of acrylonitrile. Details are not prescribed
nor is any EPA endorsement given or implied to any of these sampling and
analysis procedures. At this time, EPA has generally not evaluated these
methods. Consequently, this document merely provides an overview of
applicable source sampling procedures, citing references for those
interested in conducting source tests.
This document does not contain any discussion of health or other
environmental effects of acrylonitrile, nor does it include any discussion
of ambient air levels or ambient air monitoring techniques.
Comments on the contents or usefulness of this document are welcomed,
as is any information on process descriptions, operating practices, control
measures and emissions information that would enable EPA to improve its
contents. All comments should be sent to:
Chief, Source Analysis Section (MD-14)
Air Management Technology Branch
U. S. Environmental Protection Agency
Research Triangle Park, N. C. 27711
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SECTION 3
BACKGROUND
NATURE OF POLLUTANT
Acrylonitrile is a colorless liquid at normal temperatures and pressure
and has a faint characteristic odor. The chemical formula for acrylonitrile
is CH2=CH-C=N. Acrylonitrile has several synonyms and tradenames including
propenenitrile, vinyl cyanide, cyanoethylene, AeryIonP^ Carbacryl,®
(Rj
Fumigrain^-'and VentoxS-' Selected physical and chemical properties of
acrylonitrile are presented in Table I.1
Acrylonitrile is relatively volatile with a vapor pressure of 13.3 kPa
(1.9 psi) at 25°C (77°F) and a boiling point of 77.3°C (171.1°F). It readily
ignites and can form explosive mixtures with air. In addition, acrylonitrile
polymerizes explosively in the presence of strong alkalinity. AcrylonfErile
is photochemically reactive and has an estimated atmospheric residence time
5.6 days. Atmospheric residence time represents the time required for a
quantity of an individual chemical to be reduced to 1/e (37 percent) of its
2
original value.
OVERVIEW OF PRODUCTION AND USE
Acrylonitrile monomer is currently produced by four companies at six
manufacturing sites. Table 2 lists acrylonitrile producers and their
3 fi
manufacturing locations. In 1982, 914 Gg (2,016 x 10 Ibs) of acrylonitrile
monomer were actually produced.
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TABLE 1. PHYSICAL AND CHEMICAL PROPERTIES OF ACRYLONITRILEa'b)C
Property
Value
Molecular weight
Boiling point, °C
Freezing point, °C
Critical pressure, kPa
Critical temperature,,°C
Density at 20°C, g/cm
Viscosity, mPa-s (or cP)
Vapor density (theoretical)
Dielectric constant, at 33.5 MHz
Dipole moment, cm
Vapor pressure, kPa
8.7°C
23.6°C
45.5°C
64.7°C
77.3°C
Flash point, °C, tag open cup
Ignition temperature, °C
Explosive limits in air, vol %
Entropy of vapor, kJ/mol
Heat of formation of vapor, kJ/mol
Heat of combustion of liquid, 25°C, kJ/mol
Latent heat of vaporization, kJ/mol
Latent heat of fusion, kJ/mol
Molar heat capacity of liquid, kJ/(kg-K)
Molar heat capacity of vapor of 50°C
(kJ/(kg-K)
Solubility in water at 20°C, g/lOOg H_0
53.06
77.3
-83.55 ± 0.05
3536
246
.806
0.34
1.83 (air = 1.0)
38
1.171 x 10 (liquid
_9q phase)
.1.294 x 10 zy(vapor
phase)
6.7
13.3
33.3
66.7
101.3
-5
481
3.05-17.0 ± 0.5
274.06
185.02
1761.47
32.65
6635
2.09
1.204
7.35
Reference 1.
Synonyms: Propenenitrile , vinyl cyanide, cyanoethylene
No. 107-13-1.
CAS Registry
Properties at 25°C and 101.3 kPa unless otherwise indicated.
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TABLE 2. ACRYLONITRILE MONOMER PRODUCTION SITES3
a
Company Location
American Cyanamid Company Avondale, Louisiana
E.I duPont de Nemours &
Company, Inc. Beaumont, Texas
Monsanto Company Chocolate Bayou, Texas
Texas City, Texas
The Standard Oil Company
(Ohio)
Vistron Corp. (subsid.) Green Lake, Texas
Lima, Ohio
locations given in the literature for some of these plants vary even
though the plant is the same. Alternate locations for those given
above are as follows.
American Cyanamid: Avondale or Westwego, LA
Monsanto: Chocolate Bayou or Alvin, TX
Standard Oil: Green Lake or Victoria, TX
NOTE: This listing is subject to change as market conditions change,
facility ownership changes, plants are closed down, etc.
The reader should verify the existence of particular facilities
by consulting current listings and/or the plants themselves.
The level of acrylonitrile emissions from any given facility is
a function of variables such as capacity, throughput, and control
measures, and should be determined through direct contacts with
plant personnel.
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A single process, the Sohio process of propylene ammoxidation, is used by
all domestic producers of acrylonitrile. In this process, near stoichiometric
ratios of propylene, ammonia, and air are reacted in a fluidized bed at a
temperature of about 450°C (850°F) and a pressure of 200 kPa (2 atm) in the
presence of a catalyst. Acrylonitrile is the major product of this reaction,
but byproducts acetonitrile and hydrogen cyanide together account for about
25 percent of the total yield. The reactor product stream is quenched and
neutralized to remove unreacted ammonia. Wastewater and light gases are then
removed in separate operations. Finally, acrylonitrile, acetonitrile, and
hydrogen cyanide are separated by a series of distillations.
The major end use of acrylonitrile is in the production of acrylic
fibers. It is also used in the production of plastics such as acryloni-
trile-butadiene-styrene (ABS) and styrene acrylonitrile (SAN). ABS is used
primarily in pipes and fittings, automotive parts and applicances. SAN is
used most widely in appliances and other household items such as coat hangers,
ice buckets, jars, and disposable utensils. Another use of acrylonitrile is
in the production of nitrile rubbers and nitrile barrier resins. Nitrile
rubbers are used extensively in the engineering and process industries due to
their good dielectric properties and their resistance to chemicals, oil,
solvents, heat, aging, and abrasion. Nitrile barrier resins have the
potential for rapid future growth in the food, cosmetic, beverage, and
chemical packaging industries. Acrylonitrile is also used in the production
of adiponitrile, an intermediate in the manufacture of nylon, and in the
production of acrylamide, which is used in a variety of chemical products.
Miscellaneous uses of acrylonitrile include cyanoethylation of alcohols and
other amines, production of fatty amines, organic synthesis of glutamic acid,
use as an absorbent, and use in fumigant formulations. Figure 1 shows how the
market for acrylonitrile is distributed and Table 3 presents an approximate
breakdown of acrylonitrile consumption by product type. Table 4 lists the
major consumers of acrylonitrile by product type. The manufacturers and
consumers of acrylonitrile and acrylonitrile products may change over time due
to changes in market conditions. Publications such as the Stanford Research
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TABLE 3. ESTIMATED CONSUMPTION OF ACRYLONITRILE BY PRODUCT TYPE IN 19796"9
% TOTAL ACRYLONITRILE CONSUMPTION
Fibers 37.7
Exports 21 3
ABS/SAN Resins 17>1
Adiponitrile 9^5
Acrylamide 3 f±
Nitrile Elastomers 2.9
Barrier Resins It2
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Includes fumigants for tobacco, super absorbents, fatty amine production,
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Institute (SRI) Directory of Chemical Producers and the Chemical Marketing
Reporter (Schnell Publishing, New York) are good sources of up-to-date
information on chemical producers. Chemical trade associations such as the
Chemical Manufacturers Association, the Acrylonitrile Group, and the Synthetic
Organic Chemical Manufacturers Association would also be good contacts to
determine the status of the acrylonitrile industry.
Some potential exists for volatile substances, including acrylonitrile,
to be emitted from waste treatment, storage and handling facilities.
Reference 11 provides general theoretical models for estimating volatile
substance emissions from a number of generic kinds of waste handling
operations, including surface impoundments, landfills, landfarming (land
treatment) operations, wastewater treatment systems, and drum storage/handling
processes. Since no test data were available on acrylonitrile emissions from
any of these operations at the time of publication, no further discussion is
presented in this document. If such a facility is known to handle
acrylonitrile, the potential should be considered for some air emissions to
occur.
13
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REFERENCES FOR SECTION 3
1. Kirk-Othmer Encyclopedia of Chemical Technology. Third Edition.
Volume 1. Acrylonitrile. John Wiley and Sons, New York, NY, 1980.
pp. 414-426.
2. Cupitt, L. T. (U. S. EPA). Fate of Toxic and Hazardous Materials in the
Air Environment. EPA-600/3-80-084. August 1980. pp. 20-22.
3. Stanford Research Institute International. 1983 Directory of Chemical
Producers. Menlo Park, California. 1983. pp. 410-411.
4. Chemical Engineering News. May 2, 1983. p. 11.
5. Blackford, J. L., et_ al_. Chemical Conversion Factors and Yields,
Commercial and Theoretical. Second Edition. Stanford Research
Institute, Menlo Park, California. 1977. p. 6.
6. Textile Economics Bureau, Inc. Textile Organon. New York.
February 1981.
7. Stanford Research Institute. 1978 Chemical Economics Handbook. Menlo
Park, California. 1978. p. 607.5032J.
8. United States .International Trade Commission. Synthetic Organic
Chemicals, United States Productions and Sales. 1979.
9. 1980 Facts and Figures of the Plastics Industry. Society of the Plastics
Industry. New York. 1980.
10. Reference 3, pp. 300, 409, 412, 569, 593, 814, and 831.
11. Evaluation and Selection of Models for Estimating Air Emissions from
Hazardous Waste Treatment, Storage, and Disposal Facilities. Revised
Draft Final Report. Prepared for the U. S. Environmental Protection
Agency under Contract Number 68-02-3168, Assignment No. 77 by GCA
Corporation, Bedford, Mass. May 1983.
14
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SECTION 4
EMISSIONS FROM ACRYLONITRILE PRODUCTION
The potential for acrylonitrile emissions occurs both during the
production of the monomer and during its consumption as a raw material in
other manufacturing processes; This section includes a detailed description
of the acrylonitrile production process along with possible emitting
operations. Emission factors relating acrylonitrile emissions to
acrylonitrile production rates are also presented. Manufacturing processes
that use acrylonitrile monomer as a raw material are similarly discussed in
Section 5.
ACRYLONITRILE PRODUCTION
1—3
Process Description
Acrylonitrile is produced domestically by a single process - the Sohio
process of propylene ammoxidation . Four companies at six locations currently
ft
use this process. A simplified flow diagram of the basic Sohio process is
presented in Figure 2, and explanations of the stream codes in Figure 2 are
given in Table 5. The reaction governing the production of acrylonitrile is:
2CH2=CH-CH3 + 2NH3 + 302 •»• 2CH2=CH-CN + 6H.O.
Propylene, ammonia (NH_) , and air are fed to the reactor (Stream 4) in
near stoichiometric ratios. The molar ratio of propylene /ammonia/air fed to
the reactor is typically 1/1.06/8.4. A slight excess of ammonia forces the
reaction closer to completion and a slight excess of air continually
regenerates the catalyst used in the reaction. Raw material specifications
call for the use of refinery-grade propylene (90+ percent purity) and
fertilizer- or refrigerant-grade ammonia (99.5+ percent purity). The
15
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TABLE 5. STREAM, VENT, AND DISCHARGE CODES FOR FIGURE 21'2
Stream/Vent/Discharge Description
Stream
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
Vent/Discharge
A
B
C
D
E
F
G
H
I
J
K
L
Propylene feed
Ammonia feed
Process air
Reactor feed
Reactor product
Cooled reactor product
Sulfuric acid
Quenched reactor product
Stripping steam
Wastewater column volatiles
Absorber bottoms
Crude acrylonitrile
Crude acetonitrile
Water recycle
Acetonitrile
Hydrogen cyanide
Light ends column bottoms
Product acrylonitrile
Heavy ends
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Absorber vent gas
Recovery column purge vent
Acetonitrile column bottoms
Acetonitrile column purge vent
Light ends column purge vent
Product column purge vent
Flare
Acetonitrile incinerator stack gas
Storage tank emissions
Product transport loading facility vent
Fugitive losses from pumps, compressors, and valves
17
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vapor-phase reaction takes place in a fluidized bed reactor at approximately
200 kPa (2 atm) and 400-510'C (750-950°F) in the presence of Catalyst 41, a
Sohio-developed product. The composition of this catalyst is described in the
patent literature as 70 percent by weight P^rBi^rMoC^ in a molar ratio of
1:9:24. The conversion of propylene in the reactor is essentially complete.
The yield of acrylonitrile monomer from this reaction is typically 73 weight
percent with approximately 12 weight percent yields of each of the byproducts
acetonitrile and hydrogen cyanide (HCN).6 The stream exiting the reactor
(Stream 5) contains not only acrylonitrile and byproducts but also unreacted
oxygen, propylene, carbon monoxide, carbon dioxide, and nitrogen.
The propylene ammoxidation reaction generates substantial quantities of
heat which must be removed. Heat removal from the product stream (Stream 5)
is generally accomplished by utilizing excess heat to generate steam in a
waste heat boiler. The cooled product stream leaving the waste heat boiler
(Stream 6) passes to a water quench tower where sulfuric acid (Stream 7) is
added to neutralize unreacted ammonia. Wastewater containing the ammonium
salts and spent catalyst fines is passed through a steam stripping column
where volatiles are separated out and recycled to the quench tower
(Stream 10). Wastewater containing ammonium sulfate and heavy hydrocarbons is
discharged to a deep well pond for disposal (Discharge A).
Meanwhile, the quenched product stream (Stream 8) is passed to a counter-
current absorber which removes inert gases and vents them to the atmosphere
(Vent B). In some cases the absorber vent gas is incinerated prior to release
to the atmosphere. The stream containing acrylonitrile, acetonitrile, HCN,
and some water (Stream 11) then undergoes a series of atmospheric
distillations to obtain products and byproducts of the desired purity, as
described below.
In the first recovery column, acrylonitrile and HCN (Stream 12) are
separated from acetonitrile and water (Stream 13). Water is then removed from
the acetonitrile in the acetonitrile column and recycled to the absorber
18
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(Stream 14). The heavy bottoms from the acetonitrile column are discharged to
the deep well pond (Discharge D). The acetonitrile byproduct (Stream 15) may
be recovered to 99+ percent purity for commercial sales but, due to lack of
demand, the stream is usually incinerated.2*7
The crude acrylonitrile exiting the first recovery column (Stream 12) is
passed to storage facilities and then to a light-ends column where HCN is
recovered. The HCN byproduct (Stream 16) may be further purified to
99+ percent for sales. All acrylonitrile producers currently market a small
percentage of HCN, but the majority of the byproduct is incinerated.7 In the
final product column, heavy ends are removed (Stream 19) and incinerated. The
heavy ends stream from the product column contains essentially no
acrylonitrile. The acrylonitrile product (Stream 18) obtained from the Sohio
process has a purity of 99+ percent.
Emissions
Emissions of acrylonitrile produced via the Sohio process may occur from
several sources including the absorber vent, column purge vents, storage
tanks, transport and loading facilities, and deep well ponds. Fugitive
emissions may also occur from leaks in pumps, compressors, and valves. These
emission sources are depicted in Figure 2. Acrylonitrile emissions represent
only a small fraction of the total VOC emitted from these sources, accounting
for approximately 6 weight percent of the total uncontrolled VOC emissions and
15 weight percent of the total VOC emissions after typical controls.8
Process Emissions—
Acrylonitrile process emissions from the Sohio process occur from the
absorber vent (Vent B) during normal operation, the absorber vent (Vent B)
during startup, and the distillation column purge vents(Vents C, E, F and G)
during normal operation. During normal operation, the absorber vent gas
contains only about 0.001 weight percent acrylonitrile and 1.25 weight percent
total VOC. The absorber gases are usually incinerated at removal
19
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efficiencies of 98 percent or higher. The majority of the acrylonitrile
production facilities utilize thermal incineration, although one facility has
ey
employed catalytic incineration on the absorber vent. Because of the large
percentage (97+ percent) of nitrogen and other noncombustibles normally
present in the absorber vent gas stream, supplemental fuel must be added to
g
ensure proper combustion.
Emissions of acrylonitrile during startup are substantially higher than
during normal operation, even when averaged over an entire year on a mass per
unit time basis. During startup the reactor is heated to operating
temperature before the reactants (propylene and ammonia) are introduced.
Thus» the reactor product stream is initially oxygen-rich. As the startup
progresses and the reactants are introduced, the acrylonitrile and VOC content
of the reactor effluent increases until the acrylonitrile-rich composition
indicative of normal operation is reached. During part of this startup
process, the composition of the reactor product stream is within its explosive
limits and must, therefore, be vented to the atmosphere to prevent explosions
in the lines to the absorber. Emissions of acrylonitrile from a single
reactor during startup may be as high as 4500 kg/hr (10,000 lbs/hr).8
However, emissions associated with startup occur rather infrequently, with
each reactor having about four startups of 1-hour duration per year. Even so,
acrylonitrile emissions during startup totalled over an entire year are higher
than emissions from the absorber vent during normal operation. Incineration
may be an acceptable method of control for startup emissions but is not
generally used due to the potentially high NO emissions which could result
2S
from the combustion of a stream containing a large percentage of
acrylonitrile, hydrogen cyanide, and acetonitrile.
The acrylonitrile content of the combined column purge vent gases
(Vents C, E, F, and G) is high, about 50 weight percent of the total VOC
8
emitted from the columns. The vent gases from the recovery, acetonitrile,
light-ends, and product columns are typically controlled by a single flare.
No acrylonitrile emissions are expected from the incineration of byproduct
acetonitrile (Vent I).
20
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Other Emissions—
Acrylonitrile is emitted from crude acrylonitrile storage tanks (Vent J),
acrylonitrile run tanks (Vent J), product storage tanks (Vent J), and during
loading into railroad tank cars and barges (Vent K). These emissions are
generally uncontrolled but in some cases safety considerations dictate the use
of recovery systems. Water scrubbers used for this purpose in acrylonitrile
production facilities have demonstrated removal efficiencies up to
Q *
99 percent. Floating roof tanks may also be used in place of fixed roof
tanks to reduce acrylonitrile emissions up to 95 percent.8
Emissions of acrylonitrile may also occur from fugitive sources (Vent L)
and from deep well ponds. Fugitive sources, such as leaks from pumps,
compressors, and valves, are normally uncontrolled but can be minimized if
fugitive leaks are detected and corrected. Fugitive emissions and various
control measures used to minimize them are described in Reference 9.
Emissions of acrylonitrile from deep well ponds are usually very small because
the wastewater discharged to the deep well pond contains less than
0.02 percent acrylonitrile and the surface is covered with high molecular
weight oil to prevent the escape of most VOC vapors.2'8'10
Emission Factors— ' •
Table 6 gives acrylonitrile emission factors before and after the
application of possible controls for a hypothetical plant using the Sohio
process. The hypothetical plant is assumed to use thermal incineration for
the control of absorber vent gases, flares for the control of column purge
vents, and water scrubbers for the control of storage tank and loading
emissions. The values presented for controlled fugitive emissions are based
on the assumption that leaks from valves and pumps, resulting in concen-
trations greater than 10,000 ppm acrylonitrile on a volume basis, are detected
and that appropriate measures are taken to correct the leaks. Only the
startup emissions are uncontrolled. Uncontrolled emission factors are based
on the assumptions given in footnotes to Table 6. An annual average emission
21
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TABLE 6.
UNCONTROLLED AND CONTROLLED 'ACRYLONITRILE EMISSION FACTORS
FOR A HYPOTHETICAL ACRYLONITRILE PRODUCTION PLANT*»b
Tent0 Source
(normal)
(startup)*
C,E,r,G Column vents
X
J Storage vents
Crude acrylonitrile
Acrylonitrile run tanks
Acrylonitrile storage
j ^
K Handling1'3
Tank car loading*
*
Barge loading
1 Fugitive™
TOTAL
Uncontrolled
Emission
Factor
S/kg3
0.10
0.187
5.00
0.048s
0.128s
0.531s
0.167
0.150
0.806
7.07
Control Device
or Technique
Thermal incinerator
Ho Control
Flare (Vent H)
Water Scrubber11
Water Scrubber*1
Water Scrubber*1
Hater Scrubber
Water Scrubber
Detection and
correction of
major leaks
Controlled
Assumed
Emission
Reduction
(*>
98°
98°
99«
99"
99»
99a
99a
71
Emission
Factor
8/kg3
0.002
0.187
0.10
0.00048
0.00128
0.00531
0.0017
0.0011
0.238
0.537
* a98t00° tOM) Per *"r o£ *=ryl°»ltrile monomer. It also produce,
cSee Figure 2.
g of acrylonltrile emitted per kg acrylonitrile produced. '
year each lasting
Tank
Crude Acrylonitrile
Acrylonitrile run
tanka (two tanks)
Acrylonitrile storage
(two tanks)
^Reference 11. Section 4.3.
to the atmosphere to prevent possible explosion
v "I?" ye*r* b«sed on 8 startups (two reactors, eacn wa.cn tour startups)
hour. Thus, during startup each reactor emits 4250 kg (1930 Ib) acrylonltrile
be f J -
of 27
Yolu
»-
(m3)
2500
380
5680
Supplement 12.
Turnover, per year per tank
6
294
20
r? conero1 •tor'ge
R«f«r«nc« 11. Section 4.4. Supplement 9.
^Aasuaas 55 percent of acrylonitrile loaded into tank cars and 45 percent onto barges.
ASSUMS submerged losding and dedicated normal service..
Assumes submerged loading..
process pumps and valves are potential sources of fugitive emissions of acrylonitrile
The as.u»d equip^nt list (Reference 8) and emission factor, (Reference £) are", follow,
Equipment
25 pumps in light-liquid service
100 pipeline valves in gas/vapor service
500 pipeline valves In light-liquid service
40 safety/relief valves in gas/vapor service
S.SS
Baission Factor (kg/hr). each gimp/valve
Uncontrolled Controlled
0.12
0.021
0.010
0.16
0.03
0,002
0,003
0..061
HUferences 14 and 15.
°Kaference 16.
22
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rate of acrylonitrile from the hypothetical controlled facility shown in
Table 6 is slightly greater than 0.5 g/kg of acrylonitrile produced, including
startup emissions. However, some facilities in the acrylonitrile production
industry may have controlled emission factors two to three times higher than
the hypothetical plant described here due to differences in operating
p i -a
conditions or control methods.
23
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-------
REFERENCES FOR SECTION 4
1. Anguin, M. T. and S. Anderson (Acurex Corporation). Acrylonitrile Plant
Air Pollution Control. EPA-600/2-79-048. U.S. Environmental Protection
Agency. Research Triangle Park, North Carolina. February 1979.
2. Tierney, D. R., T. R. Blackwood, and G. E. Wilkins. Status Assessment of
Toxic Chemicals: Acrylonitrile. EPA-600/2-79-210a. U.S. Environmental
Protection Agency. Cincinnati, Ohio. December 1977.
3. Industrial Process Profiles for Environmental Use: Chapter 6: The
Industrial Organic Chemicals Industry. EPA-600/2-77-023f. U.S.
Environmental Protection Agency. Cincinnati, Ohio. February 1977.
4. Stanford Research Institute International. 1983 Directory of Chemical
Producers. Mehlo Park, California. 1983. pp. 410-411.
5. Lowenbach, W. and J. Schleslinger. Acrylonitrile Manufacture: Pollutant
Prediction and Abatement. (Prepared for U. S. Environmental Protection
Agency, EPA Contract No. 68-01-3188). The MITRE Corporation. McLean,
Virginia. February 1978.
6. Blackford, J. L, e_t al. Chemical Conversion Factors and Yields,
Commercial and Theoretical. Second Edition. Stanford Research
Institute. Menlo Park, California. 1977. p.-6.
7. Control Techniques for Volatile Organic Emissions from Stationary
Sources. EPA-450/2-78-022. U.S. Environmental Protection Agency.
Research Triangle Park, North Carolina. May 1978.
8. Key, J. A. and F. T. Hobbs (IT Enviroscience). Acrylonitrile. Organic
Chemical Manufacturing Volume 10: Selected Processes.
EPA-450-3/80-028e. U.S. Environmental Protection Agency. Research
Triangle Park, North Carolina. December 1980.
9. VOC Fugitive Emissions in Synthetic Organic Chemicals Manufacturing
Industry—Background Information for Proposed Standards.
EPA-450/3-80-033a. U.S. Environmental Protection Agency. Research
Triangle Park, North Carolina. November 1980.
10. Hughes, T. W. and D. A. Hour (Monsanto Research Corp.). Source
Assessment: Acrylonitrile Manufacture (Air Emissions). EPA Contract
No. 68-02-1874. September 1977. pp. 21-22,
11. Compilation of Air Pollutant Emission Factors. 3rd Edition. AP-42.
U.S. Environmental Protection Agency. Research Triangle Park, North
Carolina. August 1977.
24
-------
12.
13.
14.
15.
16,
Dubose, D. A. e± al (Radian Corporation). Emission Factors and Frequency
of Leak Occurrence for Fittings in Refinery Process Units.
EPA-600/2-79-044. U.S. Environmental Protection Agency. Research
Triangle Park, North Carolina. February 1979.
Suta, Benjamin (SRI International). Assessment of Human Exposures to
Atmospheric Acrylonitrile. Human Exposure to Atmospheric Concentrations
of Selected Chemicals. ' EPA Contract No. 68-02-2835. U.S. Environmental
Protection Agency. Research Triangle Park, North Carolina, August 1979.
Memo from Mascone, D. C., U. S. EPA to Farmer, J. R., U. S. EPA.
June 11, 1980. Thermal Incinerator Performance for NSPS.
Memo from Mascone, D. C., U. S. EPA to Farmer, J. R., U. S. EPA.
July 22, 1980. Thermal Incinerator Performance for NSPS, Addendum.
McDaniel, M. D. A Report on a Flare Efficiency Study, Volume 1 (Draft).
Engineering-Science. Austin, Texas. 1983.
25
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SECTION 5
EMISSIONS FROM INDUSTRIES USING ACRYLONITRILE AS A FEEDSTOCK
This section describes various production processes using acrylonitrile
monomer as a feedstock and discusses the emissions resulting from these
processes. The processes included are acrylic and modacrylic fiber
production, production of ABS/SAN resins, production of nitrile rubbers, and
the production of acrylamide and adiponitrile. The process descriptions
included in this section are for hypothetical plants generally achieving a
high degree of monomer recovery and emission control through the use of
flashing, stripping, and scrubbing. The reader should note, however, that
all facilities may not be as adequately equipped for monomer recovery and
emissions control as these hypothetical plants.
Acrylonitrile is also used as a feedstock in the production of nitrile
barrier resins, in the production of fatty amines, in the cyanoethylation of
alcohols and amines, in fumigant formulations, and as an absorbent. However,
the percentage of acrylonitrile consumed in these miscellaneous processes is
small and very limited information is available concerning process descrip-
tions and emissions. Consequently, no discussion of these miscellaneous
processes is included in this report.
ACRYLIC AND MODACRYLIC FIBER PRODUCTION1'9
The major use of the acrylonitrile monomer is as a feedstock for acrylic
and modacrylic fiber production. Acrylic fibers are classified as having
greater than 85 weight percent acrylonitrile while modacrylic fibers have less
than 85 percent but greater than 35 percent acrylonitrile. Comonomers used in
the production of acrylic fibers include methyl aerylate, methyl methacrylate,
and vinyl acetate. Vinylidene chloride and vinyl chloride are the most often
26
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used comonomers in the production of modacrylic fibers. In the remainder of
this section, acrylic and modacrylic fibers will both be referred to as
acrylic.
Process Descriptions
In the production of acrylic fibers, the acrylonitrile and comonomers are
first polymerized using either a suspension or a solution polymerization
process. The resulting polymer is then spun into fibers using either wet
spinning or dry spinning techniques. Finally, the spun fibers must be treated
to remove excess solvent and to improve fiber characteristics. The fiber
treating process has a negligible contribution to acrylonitrile emissions and
is not discussed in this section. Each of the polymerization and spinning
processes is discussed below.
Polymerization—
In 1977-78 the suspension polymerization process accounted for 87 percent
of the total acrylic fiber production, while the solution process accounted
for 13 percent. -Each-of these processes may be carried out in either a batch
or a continuous mode. A general block flow diagram is shown in Figure 3
indicating the process operations involved in the suspension and solution
polymerization processes. In the suspension process, insoluble beads of
polymer are formed in a suspension reactor. Unreacted monomer is removed from
the polymer by flashing/stripping and the polymer is filtered, dried, and then
dissolved in solvent in preparation for spinning. In the solution process,
polymer formed in the reactor is soluble in the spinning solvent present.
Reactor effluent, after monomer recovery, is therefore ready for spinning.
Several steps, including filtration and drying, are thus avoided using the
solution process.
Suspension Polymerization—
A more detailed schematic flow diagram of a hypothetical suspension
polymerization process is shown in Figure 4. Slight variations in this
27
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process may occur from plant to'plant, however. In this process acrylonitrile
and comonomers are mixed and then passed to the polymerization reactors along
with water, suspending agents, stabilizers, and catalysts. The reactor is
equipped for heat removal and is agitated to maintain the monomers in
suspension in the water. The reaction of acrylonitrile monomers in the
suspension reactor is typically carried out to about 65 to 85 percent
completion, and results in the formation of insoluble beads of polymer.
Essentially all of the comonomers are consumed in this process.
Unreacted acrylonitrile monomer is removed from the polymer product by
flashing and stripping. Approximately 80 percent of the unreacted monomer is
released overhead from the vacuum flash tank and nearly all of the remaining
acrylonitrile is released overhead by countercurrent contact with steam in the
slurry stripper. The acrylonitrile-containing streams from the vacuum flash
tank and slurry stripper are passed to the acrylonitrile recovery unit. Some
acrylonitrile is also recovered from the reactor and slurry stripper overhead
condensers and decanters (not shown in Figure 4).
The stripper bottoms, containing stripped polymer and water, are pumped
via a filter feed tank to the filtration unit, typically consisting of two
rotary vacuum filters. These filters serve to concentrate the polymer in a
cake to reduce the load in the dryers and to remove most of the residual
acrylonitrile from the polymer. Filter cake from the first filter is
reslurried with water and transferred to the second filter. Filter cake from
the second filter is pelletized and filtrate is transferred to the
acrylonitrile recovery system. The pelletized polymer is then dried with
steam heated air and stored in bins or silos. In preparation for spinning
into fiber, the dry polymer is mixed with solvent and dissolved to form
spinning dope which is then filtered, deaerated, and pumped to the spinneret
which is a metal plate perforated with 200-30,000 holes of approximately
0.008 cm (0.003 in) diameter.
30
-------
Acrylonitrile recovery is accomplished by the use of an absorber/stripper
system. Acrylonitrile-containing gases from the reactor, vacuum flash tank,
slurry stripper, filter feed tank, filters, pelletizer, and recovered
acrylonitrile tank are scrubbed with water in the acrylonitrile absorber.
Absorber overhead is vented to the atmosphere and absorber bottoms are sent to
the acrylonitrile stripper, along with filtrate from the rotary filters.
Acrylonitrile monomer is released overhead along with a considerable amount of
steam. An overhead condenser followed by a decanter serves to separate the
acrylonitrile from the water. The water-rich phase is treated and recycled to
the stripper and the acrylonitrile-rich phase is recycled to the recovered
acrylonitrile tank.
Solution Polymerization—
The basic process flow diagram for solution polymerization is similar to
that for suspension polymerization (shown in Figure 4) except that the
filtration, pelletizing, and drying steps are eliminated. In the solution
polymerization process, acrylonitrile and comonomers are fed to a monomer mix
tank where they are dissolved in a solvent. Typical solvents include organic
solvents such as dimethylformamide (DMF), dimethylacetamide (BMAC) or acetone,
and concentrated aqueous solutions of zinc chloride, sodium thiocyanate, or
nitric acid. The monomer/solvent solution is transferred to the
polymerization reactors where addition of an initiator causes the reaction to
proceed. Polymer formed by solution polymerization is soluble in the solvent.
The polymer solution is flashed to release about 80 percent of the unreacted
acrylonitrile monomer, and then pumped to the top of the stripper where
virtually all of the remaining acrylonitrile monomer is stripped overhead by
countercurrent contact with steam. The stripper overhead stream is vented to
the atmosphere. Finally, the stripped polymer solution is heated, filtered,
deaerated and pumped to the spinnerets to be spun into fibers.
An absorber/stripper system is used to recover imreacted acrylonitrile
from gases generated by storage tanks, the reactor, and the vacuum flash tank.
This absorber/stripper system is similar to the one used in the suspension
31
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polymerization process. The acrylonitrile-containing gases are scrubbed with
water in the acrylonitrile absorber and overhead from the absorber is vented
to the atmosphere. Bottoms from the absorber are pumped to the acrylonitrile
stripper where acrylonitrile monomer is stripped overhead with steam. Phase
separation is accomplished by means of a condenser and decanter, and the
water-rich phase is returned to the stripper while the acrylonitrile-rich
phase is recycled to the polymerization reactor.
Spinning—
Acrylic and modacrylic fibers may be spun in either a wet spinning or a
dry spinning process. Wet spinning may be carried out in a batch or a
batch-continuous process whereas dry spinning is always a batch process. Both
the wet spinning and dry spinning processes require that the polymer be
dissolved in solvent, forming a viscous solution that is then forced through a
spinneret. Common spinning solvents are acetone and dimethylformamide.
The main difference between the wet and dry spinning processes is the
method used to remove solvent from the fiber upon extrusion from the
spinneret. In the dry spinning process, the solvent is evaporated by hot
gases, while in the wet spinning process the solvent is removed by leaching or
2
washing. The wet fibers produced by wet spinning must then be dried in an
air dryer. The resulting fibers from both processes are then stretched,
crimped, and thermally stabilized.
Vaporized solvent from the dry spinning process is condensed and recycled
to the dissolving step of the polymerization process. Wash water from the wet
spinning process, containing solvent and some residual acrylonitrile monomer,
is directed to a solvent recovery unit and an acrylonitrile recovery unit. In
some cases, the exhaust from the fiber dryer is also sent to the solvent
recovery unit.
32
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Emissions
Acrylonitrile emissions from the combination of suspension polymerization
followed by wet spinning occur at the pelletizer and polymer dryer. Potential
emissions of acrylonitrile from the polymerization reactor, flash tank, slurry
stripper, filter feed tank and filters, and pelletizer are reduced by passing
the vent gases through an absorber/stripping system for acrylonitrile
recovery. Acrylonitrile emissions from this absorber/stripping system'are
very low. Emissions from the combination of solution polymerization followed
by wet spinning may occur at the stripper and in the spinning and washing
steps. Potential acrylonitrile emissions from the polymerization reactor and
flash tank are reduced by passing the vent gases through the acrylonitrile
recovery unit. Some of the emissions associated with spinning and washing may
also be reduced in this manner. Monomer storage tank vents for both processes
are generally controlled by flares. Fugitive emissions from pumps, valves,
and seals may also occur during the production of acrylic fibers. Information
concerning acrylonitrile emissions from the dry spinning process is not
available. Also, no information concerning reactor startup emissions is
available.
Many of the controls typically employed at acrylic fiber production
facilities are integral parts of the process design. Most of the controls are
actually recovery systems which reduce downstream emissions in addition to
recovering monomer for reuse in the process. Strippers, scrubbers,
condensers, and flash systems are used for recovery purposes. In the
suspension process, unreacted monomer is also removed from the polymer in the
washing and filtration step's. Most of these controls remove unreacted monomer
from the polymer thereby reducing the amount of monomer that would otherwise
be released in the drying ovens. The drying ovens are generally uncontrolled
due to the high cost of treating large air flows with dilute VOC
concentrations.
33
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Sufficient information is not available to develop emission factors for
the various process operations given above. The reader is encouraged to
contact State and local air pollution control agencies where these types of
plants are located and the specific plants of interest to determine the extent
of potential acrylonitrile emissions from fiber production.
Source Locations
Five companies at six locations produce acrylic fibers. A list of these
companies and their locations is given in Table 7.10 Acrylonitrile monomer is
not produced at any of these facilities.
The manufacturers of acrylonitrile products such as acrylic and
modacrylic fibers may change over time due to changes in market conditions.
Publications such as the SRI Directory of Chemical Producers and the Chemical
Marketing Reporter are good sources of up-to-date information on chemical
procucers. Chemical trade associations such as the Chemical Manufacturers
Association, the Acrylonitrile Group, and the Synthetic Organic Chemical
Manufacturers Association would also be good contacts to determine the status
of the acrylonitrile products industry.
PRODUCTION OF SAN AND ABS RESINS1"9'11
Acrylonitrile monomer is used extensively in the production of
styrene-acrylonitrile (SAN) resins and acrylonitrile-butadiene-styrene (ABS)
resins. SAN resins may contain up to about 35 weight percent acrylonitrile.
ABS resins are two-phase systems formed by grafting SAN onto a rubber phase
and then blending the grafted rubber with SAN. The amount of rubber in ABS
varies from 5 to 30 percent. Most SAN produced is used captively in the
production of ABS although some is marketed separately. Only one producer
manufactures SAN exclusively for sale on the merchant market.
34
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TABLE 7. DOMESTIC ACRYLIC FIBER PRODUCERS IN 198310
Location
American Cyanamid Co. Milton, Florida
Badische Corporation Williamsburg, Virginia
E. I. duPont de Nemours and Co., Inc.
Camden, South Carolina
Waynesboro, Virginia
Tennessee Eastman Co. Kingsport, Tennessee
Monsanto Co. Decatur, Alabama
NOTE: This listing is subject to change as market conditions change,
facility ownership changes, plants are closed down, etc. The
reader should verify the existence of particular facilities by
consulting current listings- and/or the plants themselves. The
level of acrylonitrile emissions from any given facility is a
function of variables such as capacity, throughput, and control
measures, and should be determined through direct contacts with
plant personnel.
35
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Process Descriptions and Emissions
ABS and SAN resins are produced by emulsion, suspension, and mass
polymerization processes. Currently most ABS and most SAN for captive use are
produced using the emulsion polymerization process. Mass polymerization is
the method most often used to produce SAN for sale in the marketplace.
Process and operating conditions used to produce SAN and ABS may vary
considerably from plant to plant depending on the composition of the finished
product. Likewise, emissions and methods of emission control and monomer
recovery may vary from plant to plant. For this reason, it is difficult to
give precise process descriptions for each of the various polymerization
processes. The process descriptions and flow diagrams presented in this
section are, therefore, very general in nature. Brief discussions of each of
the processes used to produce SAN are included in the section followed by a
discussion of methods used to produce ABS.
SAN Production Processes—
The three polymerization processes used to produce SAN are emulsion,
mass, and suspension polymerization. Simplified block diagrams of these three
processes are shown in Figure 5.
SAN produced via the emulsion polymerization process may be formed by
either a batch or a continuous process. In either process, styrene and
acrylonitrile monomers are fed to the reactor along with an emulsifier,
deionized water, and catalysts. The polymerization reaction takes place at
about 70-100°C (160-212°F) and proceeds to 90-98 percent conversion.
Unreacted monomers are recovered from the resulting SAN latex by steam
stripping. The SAN latex is then subjected to coagulation, filtration, and
drying before the solid SAN product is produced. Potential acrylonitrile
emission points include storage tanks, polymerization reactors, the latex
stripper, the coagulation tank, filters, and the dryer. However,
36
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acrylonitrile emissions from these points are generally reduced by
incinerating/flaring the vent gas streams and/or passing them through a water
scrubber.
The mass polymerization process used to produce SAN is generally a
continuous process with inherently low acrylonitrile emissions. The styrene
and acrylonitrile monomer mixture is heated together with an appropriate
modifier-solvent and pumped to the polymerizaton reactor. Polymerization
takes place in the presence of a catalyst in an agitated reactor maintained at
about 275 kPa (40 psia) and 100-200°C (212-390°F). The reaction proceeds only
to about 20 percent conversion. The conversion is limited in order to control
viscosity. The reaction products are discharged to a series of devolatilizers
that separate the SAN polymer from unreacted monomers and the
modifier-solvent. Devolatilization is carried out under vacuum at
temperatures of 120 to 260°G (250 to 500°F). Inerts, unreacted monomers, and
the modifier-solvent are removed overhead from the devolatilizers. Overheads
are condensed and passed through a refrigerated styrene scrubber to recover
monomers and modifier-solvent which are then recycled to the feed tank. The
refrigerated scrubber vent gas contains a negligible amount of acrylonitrile.
The bottoms from the final devolatilizer are almost pure polymer melt.
This polymer is extruded and chopped into pellets. The pellets are then
blended, milled and compounded. Acrylonitrile and other volatile organic
compounds that are released from the milling operation are passed through a
scrubber prior to being vented to the atmosphere. Acrylonitrile emissions
from the feed tank, reactor, and devolatilizers are vented to an
incinerator/flare.
SAN produced via the suspension polymerization process may be produced in
either a batch or a continuous mode, although batch processes are predominant.
In this process, styrene and acrylonitrile monomers are dispersed mechanically
in water containing catalysts and suspending agents. The monomer droplets are
polymerized while suspended by agitation, and insoluble beads of polymer are
38
-------
formed. The temperature of the polymerization reactor ranges from 60-150°C
(140-300°F) and a monomer conversion of 95 percent is normally achieved.
Unreacted monomer is recovered by flashing and steam or vacuum stripping. The
solid and liquid phases of the polymer slurry are separated by centrifugation
and/or filtration. The solid phase is then dried in a rotary dryer and the
dried polymer is finished by mechanically blending in dyes, antioxidants and
other additives using extruders and rolling mills. The polymer sheets from
these operations are then pelletized and packaged. Although emissions of
acrylonitrile from the various process operations described above would be
expected, information detailing these emissions and methods of control is
unavailable.
ABS Production Processes—
As mentioned previously, ABS is a two-phase system consisting of an
SAN-grafted rubber blended with SAN. Polybutadiene is normally used as the
backbone or substrate rubber but nitrile rubbers and styrene-butadiene rubbers
may also be used. The backbone rubber may be produced at the ABS facility for
captive use or it may be purchased from other sources. Like SAN, ABS may be
produced by the emulsion, mass, and suspension polymerization processes.
ABS by Emulsion Polymerization—There are three different routes by which ABS
may be produced using the emulsion polymerization process. Block diagrams for
each of these routes are depicted in Figure 6. In the first route pictured in
Figure 6a, styrene and acrylonitrile monomers are grafted onto the backbone
rubber, usually polybutadiene rubber. The SAN-grafted rubber latex is then
blended with SAN resin latex (produced by emulsion polymerization) followed by
coagulation, washing, filtration, and drying.
In the second route shown in Figure 6b, the SAN-grafted rubber is
coagulated, washed, filtered and dried. Then the dry grafted-rubber is
mechanically blended with dry SAN solid. Solid SAN copolymer produced by the
emulsion, suspension or mass polymerization processes may be utilized in the
mechanical blending step. In the third route shown in Figure 6c, the
39
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SAN-graft and styrene-acrylonitrile copolymerization occur in the same
reaction vessel. The resulting ABS latex is then coagulated, washed, filtered
and dried.
Each of these routes uses a water scrubber to recover unreacted
acrylonitrile monomer from the emulsion polymerization reactor vent gas.
Acrylonitrile emissions from the water scrubber, coagulation tank, wash tanks,
and filters are incinerated/flared before being released to the atmosphere.
Generally, emissions from the polymer dryer are uncontrolled.
ABS by Mass Polymerization—A block flow diagram for ABS produced via the mass
polymerization process is shown in Figure 7. The rubber used in this process
must be soluble in the styrene and acrylonitrile monomers. The rubber is
dissolved in the monomers along with initiators and modifiers and then passed
to the prepolymerizer, an agitated vessel where a 20 to 30 percent conversion
of the monomers occurs. The resulting monomer-polymer mixture is pumped
directly to the mass polymerization reactor where an overall conversion of
50 to 80 percent is achieved. Unreacted monomers are removed from the polymer
in a series of devolatilizers, and are then condensed and recycled to a
prepolymerizer. To produce the product resin, ABS polymer is extruded and
chopped into pellets. Acrylonitrile emission points include the
polymerization reactor, devolatilizers, and monomer vapor condenser. Vent
incineration is typically used to reduce acrylonitrile emissions from this
process.
ABS by Suspension Polymerization—The suspension polymerization process used
to produce ABS is shown by a block flow diagram in Figure 8. This process is
sometimes called a mass-suspension process because the dissolving and
prepolymerizations steps are identical to those of the mass polymerization
process. The monomer/polymer mixture from the prepolymerizer is passed to the
suspension reactor to which is added water and suspending agents. When the
desired conversion is reached, the reaction products are cooled, dewatered by
filtration or centrifugation, and dried. Possible acrylonitrile emission
41
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43
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sources from this process include the prepolymerizer, polymerization reactor,
dewatering system, and the dryer. Emissions from these sources are often
reduced by incineration.
Emissions Summary
Acrylonitrile emission sources vary depending upon the type of
polymerization process used: emulsion, mass, or suspension. Possible
emission sources and typical methods of control were previously discussed for
each of the various polymerization processes used to produce SAN and ABS. In
addition to acrylonitrile emissions from the various process operations,
fugitive emissions of acrylonitrile from pumps, valves, and flanges may also
occur. Sufficient information was unavailable to develop emission factors for
specific facilities, process operations, or fugitive emission sources. Also,
no information concerning reactor startup emissions is available in the
literature for ABS/SAN production processes. The reader is encouraged to
contact State and local air pollution control agencies where these types of
plants are located and the specific plants of interest to determine the extent
of potential acrylonitrile emissions from ABS/SAN production.
Source Locations
ABS/SAN resins are produced by three companies at 10 locations. A list
of these producers and their locations is given in Table 8.12 Although all
ABS manufacturers have SAN production capabilities, essentially all of this
SAN is used captively in the production of ABS.
The manufacturers of acrylonitrile products such as ABS and SAN resins
may change over time due to changes in market conditions. Publications such
as the SRI Directory of Chemical Producers and the Chemical Marketing Reporter
are good sources of up-to-date information on chemical producers. Chemical
trade associations such as the Chemical Manufacturers Association, the
44
-------
TABLE 8. DOMESTIC ABS/SAN RESIN PRODUCERS IN 198312
Company Location . Products
SAN ABS
Borg-Warner Corp. Ottawa, Illinois - yes
Washington, West Virginia - yes
Port Bienville, Mississippi - yes
Dow Chemical Gales Ferry, Connecticut13 - yes
Ironton, Ohio - yes
Midland, Michigan3 yes yes
Pevely, Missouri yes
Torrance, California - yes
Monsanto Co.c Addyston, Ohio3 yes yes
Muscatine, Iowa - yes
Produce some SAN for the merchant market. Most SAN is used captively
in ABS production.
This plant is also referred to as the Allyns Point plant.
Reference 12 indicates that Monsanto has an ABS resin plant in Springfield,
Massachusetts; however, information obtained from References 13 and 14 has
more recently indicated that this facility no longer produces ABS resins.
NOTE: This listing is subject to change as market conditions change,
facility ownership changes, plants are closed down, etc. The
reader should verify the existence of particular facilities by
consulting current listings and/or the plants themselves. The
level of acrylonitrile emissions from any given facility is a
function of variables such as capacity, throughput, and control
measures, and should be determined through direct contacts with
plant personnel.
45
-------
Acrylonitrile Group, and the Synthetic Organic Chemical Manufacturers
Association would also be good contacts to determine the status of the
acrylonitrile products industry.
NITRILE RUBBER AND LATEX PRODUCTION1""9
Another use for acrylonitrile monomer is in the production of nitrile
elastomers, in both crumb rubber and latex form. The rubbers and latexes are
manufactured using the emulsion copolymerization of acrylonitrile and
butadiene. Acrylonitrile content in these nitrile products may range from
20 to 50 weight percent but is typically in the 30 to 40 percent range. The
acrylonitrile content of a particular product is dictated by the end use of
the product. The oil resistance of the product increases with increasing
acrylonitrile content, but the low temperature flexibility decreases.
Process Description
Nitrile rubbers and latexes are produced by emulsion polymerization in
batch or continuous reactors. This process involves polymerization of
acrylonitrile and butadiene monomers, recovery of unreacted monomers, and
coagulation, washing and drying.- A schematic flow diagram of the process is
shown in Figure 9.
Polymerization—
Acrylonitrile and butadiene monomers are fed to the agitated
polymerization reactors along with a soap solution and additives. Additives
include catalysts and activators, which initiate and promote the
polymerization reaction, and modifiers which control polymer properties such
as viscosity and molecular weight (chain length). Early in the reaction the
soap provides the microscopic bubbles called micelles in which the reaction
takes place. Later, the soap covers the rubber particles formed and keeps the
mixture in liquid form. The soap solution is used to produce an emulsion of
monomers in an aqueous medium.
46
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The polymerization process is carried out under either cold conditions
[4-7°C and 101 to 205 kPa (40 - 45'F and 0 to 15 psig)] using ammonia
refrigeration, to remove heat of reaction, or under hot conditions [35 - 49°c
and 377 to 515 kPa (95 - 120°F and 40 to 60 psig)] using cooling water.
Reaction times may vary considerably (from an hour to several days) depending
on the ingredients used. When the desired level of conversion has been
attained, the reaction is stopped by destroying the catalyst and adding a
shortstop solution. Two common shortstop ingredients are sodium dimethyl
dithiocarbamate and hydroquinone. Monomer conversion for rubber products is
typically 60 to 90 percent while 95 percent conversion is typical for latex
products. The resulting reaction mixture, a milky white emulsion called
latex, is sent to blowdown tanks where antioxidants are normally added to
maintain product quality.
Unreacted Monomer Recovery--
Unreacted monomers must be removed from the latex, requiring a series of
flashing and stripping operations. First, the latex is subjected to several
vacuum flash steps where most of the unreacted butadiene and some
acrylonitrile are released. Then the latex is usually stripped with steam
under vacuum to remove residual butadiene and most of the unreacted
acrylonitrile. A thorough flash/stripping operation will remove better than
99 percent of the unreacted monomers from the latex. Stripped latex at about
43 to 55°C (110 to 130°F) is pumped to blend tanks.
Butadiene and acrylonitrile monomers released from the latex
flashing/stripping operation are passed through a water absorber along with
reactor process vent gases, effecting separation of the two monomers.
Butadiene is passed to a separate recovery unit and the monomer is then
recycled to the process. Acrylonitrile monomer recovery is normally
accomplished by combining the acrylonitrile-containing streams from the
absorber and latex.stripper and passing the combined stream through a steam
stripper. Acrylonitrile released overhead from the stripper is condensed and
recycled to the process.
48
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Coagulation, Washing and Drying—
The coagulation, washing, and drying steps are omitted if the desired end
product is latex. These steps are necessary, however, for the production of
rubber. In the production of rubber, latex is first coagulated into a slurry
of fine crumbs by the addition of various salts or acids which destroy the
protective soap cover. Coagulated crumb rubber is quenched and then separated
from the coagulation liquor in a shaker screen and the liquor is recycled to
the coagulation tank along with fresh acid or brine. The screened crumb is
washed with water in a reslurry tank to remove residual coagulation liquor
from the rubber. The crumb rubber slurry is again dewatered on a second
screen. Although not depicted in Figure 9, a vacuum filter or press may be
used further to dewater the crumb which typically has a moisture content of
10 to 50 percent. The crumb rubber is then dried in a gas-fired or
steam-heated dryer where it is contacted with hot air. Finally, the nitrile
rubber product is weighed and pressed into bales in preparation for shipment.
Emissions
Essentially all of the process operations shown in Figure 9 are potential
sources of acrylonitrile emissions. However, emissions from these sources are
generally reduced through a combination of monomer recovery by absorption and
stripping, and vent incineration or flaring. Unreacted acrylonitrile and
butadiene, released from the polymerization reactor as well as from the latex
during flashing/stripping, are recovered and recycled to the process.
Acrylonitrile emissions from the acrylonitrile absorber and stripper are
negligible. Acrylonitrile emissions from polymerization reactors, the
blowdown tank, the quench tank, the coagulation tank,, wet screens, the
reslurry tank, and the dryer are typically vented to an incinerator or flare.
Fugitive emission sources include storage tanks, pumps, valves, flanges and
drains. Sufficient information is not available to develop emission factors
for various facilities, process operations, or fugitive emission sources.
Also, no information is available in the literature to accurately quantify
reactor startup emissions. The reader is encouraged to contact State and
49
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local air pollution control agencies where these types of plants are located
and the specific plants of interest to determine the extent of potential
acrylonitrile emissions from nitrile rubber and latex production.
Source Locations
Nitrile rubber is produced by five companies at seven locations. These
companies and their locations are listed in Table 9.15'16 The manufacturers
of acrylonitrile products such as nitrile rubber and latex may change over
time due to changes in market conditions. Publications such as the SRI
Directory of Chemical Producers and the Chemical Marketing Reporter are good
sources of up-to-date information on chemical producers. Chemical trade
associations such as the Chemical Manufacturers Association, the Acrylonitrile
Group, and the Synthetic Organic Chemical Manufacturers Association would also
be good contacts to determine the status of the acrylonitrile products
industry.
PRODUCTION OF ADIPONITRILE17
Adiponitrile may be produced by as many as four processes; however, only
one of these processes involves the use of acrylonitrile. Adiponitrile from
acrylonitrile involves the hydrodimerization of acrylonitrile in an
electrochemical process. This process is used only by Monsanto Company, who
is also the original process developer.
The Monsanto electro-hydrodimerization (EHD) process is represented by
the following equation:
2H2C=CHCN + 2e~ + 2H+ -»• NCCCH^CN.
This reaction takes place in an electrolytic cell, using electrical energy to
provide the impetus for the chemical reaction. Either graphite and magnetite
50
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TABLE 9. DOMESTIC NITRILE ELASTOMER PRODUCERS IN 198315>16
Company
Location
Copolymer Rubber and Chemical Corp.
BF Goodrich Co.
Goodyear Tire and Rubber Co.
Reichhold Chemical
Uniroyal, Inc.
Baton Rouge, Louisiana
Akron, Ohio
Louisville, Kentucky
Akron, Ohio
Houston, Texas
Cheswold, Delaware
Painesville, Ohio
NOTE: This listing is subject to change as market conditions change,
facility ownership changes, plants are closed down, etc. The
reader should verify the existence of particular facilities by
consulting current listings and/or the plants themselves. The
level of acrylonitrile emissions from any given facility is a
function of variables such as capacity, throughput, and control
measures, and should be determined through direct contacts with
plant personnel.
51
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or cadmium and iron may be employed as cathodes and anodes, respectively. A
tetraalkylammonium salt is used to increase conductivity and to reduce the
formation of byproduct propionitrile by hydrogenation of acrylonitrile.
The reaction itself is carried out by rapidly pumping a two-phase
emulsion through the cathode-anode system. This two-phase emulsion consists
of an aqueous phase containing the conducting salt and small amounts of
acrylonitrile, and an organic phase containing acrylonitrile and adiponitrile.
After passing through the electrolytic cell, the organic and aqueous phases
are separated by distillation. The aqueous phase containing the conducting
salt is recycled, and adiponitrile is recovered from byproducts,
propionitrile, and biscyanoethyl ether. The adiponitrile selectivity in this
reaction is approximately 90 percent.
No process information is available to formulate acrylonitrile emission
factors for the Monsanto EHD adiponitrile process. The reader is encouraged
to contact State and local air pollution control agencies where these types of
plants are located and the specific plants of interest to determine the extent
of potential acrylonitrile emissions from adiponitrile production.
The Monsanto plant where adiponitrile is produced by the EHD process is
located in Decatur, Alabama.
PRODUCTION OF ACRYLAMIDE19
Acrylamide is produced on the industrial scale by the hydration of
acrylonitrile. As shown in Table 10, three companies at four locations are
20
currently producing acrylamide. Two hydration methods are currently used in
the United States: acid hydrolysis (partial hydrolysis) and catalytic
hydrolysis (direct hydrolysis).
In the acid hydrolysis process, acrylonitrile is reacted with
stoichiometric amounts of sulfuric acid (H2S04) to form acrylamide sulfate.
52
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TABLE 10. DOMESTIC ACRYLAMIDE PRODUCERS IN 198320
Company Location
American Cyanamid Linden, New Jersey
Avondale, Louisiana3
Dow Chemical Midland, Michigan
Nalco Chemical Garyville, Louisiana
plant is also referred to in the literature as being located in
Westwego, Louisiana.
NOTE: This listing is subject to change as market conditions change,
facility ownership changes, plants are closed down, etc. The
reader should verify the existence of particular facilities by
consulting current listings and/or the plants themselves. The
level of acrylonitrile emissions from any given facility is a
function of variables such as capacity, throughput, and control
measures, and should be determined through direct contacts with
plant personnel.
53
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The acrylamide sulfate. intermediate is then reacted with ammonia (NH ),
forming acrylamide and ammonium sulfate. The equation governing the^cid
hydrolysis reaction is:
CH2=CHCN + H2S04« H20 * CH,,=CHCONH2 • ^SQ
CH2=CHCONH2
Ammonium sulfate and acrylamide are then separated by several involved
crystallization steps.
In the catalytic hydrolysis process, acrylamide is produced by the direct
hydrolysis of acrylonitrile over copper catalysts in an aqueous solution. The
advantage of this method is that, after filtering off the catalyst and
distilling to remove unreacted acrylonitrile, an essentially pure aqueous
acrylamide solution is obtained. This solution can then be used directly or
further concentrated depending upon its end use.
Information concerning emissions of acrylonitrile from the production of
acrylamide is unavailable. The reader is encouraged to contact State and
local air pollution control agencies where these types of plants are located
and the specific plants of interest to determine the extent of potential
acrylonitrile emissions from acrylamide production.
54
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-------
REFERENCES FOR SECTION 5
1. Click, C.N. and D.O. Moore. Emission, Process and Control Technology
Study of the ABS/SAN, Acrylic Fiber, and NBR Industries (prepared for
U.S. Environmental Protection Agency. Contract No. 68-02-2619, Task 6).
Pullman Kellogg. Houston, Texas. April 1979.
2. Considine, D. Chemical and Process Technology Encyclopedia.
McGraw-Hill, New York, New York. 1974. pp. 27-28.
3. Encyclopedia of Polymer Science and Technology. Volume 1: Acrylic
Fibers, p. 352.
4. 1980 Kline Guide to the Chemical Industry, pp. 343-344.
5. Work, R. W. Man-Made Textile Fibers. In:Riegel's Handbook of Industrial
Chemistry. Kent, J. (ed). Van Nostrand Reinhold. New York. 1974. p.
332.
6. Development Document for Proposed Effluent Limitations Guideline and New
Source Performance Standards for the Synthetic Resins Segment of the
Plastics and Synthetic Materials Manufacturing Point Source Category. U.
S. Environmental Protection Agency. EPA-940/1-73-010. September 1973.
p. 71.
7. Reference 1, pp. 80-85.
8. Reference 4, pp. 348-351.
9. U. S. International Trade Commission. Synthetic Organic Chemicals,
U. S. Productions and Sales. 1979.
10. Stanford Research Institute International. 1983 Directory of Chemical
Producers. Menlo Park, California. 1983. p. 593.
11. Kirk-Othmer Encyclopedia of Chemical Technology. Third Edition.
Volume 1. Acrylonitrile Polymers. John Wiley and Sons, New York, New
York. 1980. pp. 427-456.
12. Reference 10, pp. 814 and 831.
13. Letter and attachments from Romano, R. R., Chemical Manufacturers
Association to Lahre To, U. S. EPA. August 11, 1983. Comments on
emission factor reports.
14. Telecon. Lahre, T. F.s U. S. EPA with Massachusetts Department of
Environmental Quality Engineering. December 6, 1983. Status of the
Monsanto-Springfield ABS resin plant.
55
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15. Reference 10, p. 569.
16. Letter and attachments from Blower, K. E., Standard Oil to Lahre, T. F.,
U. S. EPA. June 13, 1983. Comments on the draft acrylonitrile emission
factor report.
17. Weissermel, K. and H. Arpe. Industrial Organic Chemistry: Important Raw
Materials and Intermediates. Verlag Chemie, New York, New York. 1978
pp. 216-219.
18. Reference 10, p. 412.
19. Reference 17. pp. 270-272.
20. Reference 10, p. 409.
56
- 3i
Jfc
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SECTION 6
SOURCE TEST PROCEDURES
The results of a literature survey and review of References 2 through 25
indicate that gas chromatography is the analytical method generally preferred
for acrylonitrile.1 Table 11 lists several sampling and analytical techniques
evaluated, along with their advantages and disadvantages. The major
differences among the various methods are in sample collection and
preconcentration, and the choice of detector used for quantification.
The need to concentrate samples is determined by the level of the
acrylonitrile in the sample and by the detection limit of the particular
instrumentation chosen for quantification. When acrylonitrile levels are low,
provisions must be built into the method for the determination of these low
levels.
• • • : *• ' ' • -
LITERATURE REVIEW OF SAMPLING METHODS
Although several researchers have used aqueous or aqueous/organic solvent
mixtures in bubblers or impingers for sampling acrylonitrile, the most widely
reported trapping methods are those employing solid adsorbent tubes of
charcoal, Tenax, or other porous polymers such as those used for gas
chromatographic supports. Of these solid adsorbents, the one which has
received the most attention and is used most often is Tenax-GC. However, the
data presented in the various publications surveyed in this review indicate
that the retention characteristics of acrylonitrile on Tenax are such that the
safe sampling volumes would be quite small. The safe sampling volume is
approximately 3 liters of air per gram (48 ft3 per pound) of Tenax for a flow
rate of 5 to 200 ml/min at 25°C (77°F). Because of the small sample, the
concentration factor would also be very small.
57
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TABLE 11. ADVANTAGES AND DISADVANTAGES OF ACRYLONITRILE
SAMPLING AND ANALYSIS PROCEDURES *
Method
Advantages
Disadvantages
SAMPLING
aqueous/organic
solvent bubblers
Tenax or other
GC adsorbent or
porous polymer
charcoal
ANALYSIS
gas chromatography
with flame ionization
detection (GC/FID)
simple, inexpensive
thermally desorbed
high capacity
simple, inexpensive
gas chromatography with high, sensitivity,
nitrogen specific phos- eliminates some
phorus detection (GC/NPD) interference
gas chromatography with highly specific,
mass spectroscopy (GC/MS) intermediate sensitivity
not much information
available on re-
coveries
very low sampling
volumes
poor recovery for
low levels of
analyte
not very specific,
sensitive to low
quantities, many
interferences
expected
not completely
specific
expensive
58
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For Porppak N, a porous polymer often used for GC supports, the
breakthrough volume was reported and found to be 3 to 5 liters of air at
100 ml/min at 25°C. The maximum recommended sampling volume for this sorbent
was estimated to be 50 to 75 percent of the breakthrough volume, or 1.5 to
2.5 liters. With such small concentrations, the sensitivity of the
measurement technique becomes very important.
Most sampling of air and exhaust samples for acrylonitrile is done using
charcoal. The adsorptive capacity of charcoal for acrylonitrile is on the
order of 4 percent by weight according to one report;(NIOSH method), but this
can vary depending upon the characteristics of the adsorbent. The main
problem with charcoal adsorption tubes is the possibility of losses of small
amounts of acrylonitrile upon desorption with organic solvents.
A recent investigation of recoveries of acrylonitrile from charcoal
concluded that acrylonitrile could be recovered (>90 percent) with good
precision from charcoal at a level of 16 jig per 100 mg charcoal using a
mixture of acetone and carbon disulfide instead of methanol for desorption.13
This corresponds to vapor levels of 0.5 ppm for a 15-liter air sample. Below
the 16 yg/100 mg charcoal level, recoveries were generally less than
90 percent for vapor phase application of acrylonitrile.
Because of possible low recoveries of acrylonitrile on charcoal, large
sampling volumes might be required to achieve lower detection limits, but, at
the same time, backup sections of charcoal adsorbent would be required should
the levels be higher than expected.
LITERATURE REVIEW OF ANALYTICAL PROCEDURES
The three possible choices of detectors for GC separation of
acrylonitrile are flame ionization detection, nitrogen specific detection, and
low or high resolution mass spectrometry, with or without selected ion
monitoring.
59
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Flame ionization detection (FID) can only be ussed with relatively high
levels of acrylonitrile. The use of high resolution mass spectrometry with
selected ion monitoring (SEM) is the preferred detection technique, but the
increased cost associated with SEM is prohibitive in some cases. Therefore,
the most logical choice for a detection method, based upon cost and ease of
use, is nitrogen specific detection with either a alkali flame detector (AFD),
a thermionic specific detector (TSD), or nitrogen specific phosphorus
detection (NPD). The use of nitrogen specific detection should reduce
background interferences encountered with the FID and increase sensitivity.
One source estimated the detection limit of the nitrogen specific detector at
10 Pg.10
60
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REFERENCES FOR SECTION 6
1. Cooke, M. et al. (Battelle); J.C. Harris and V. Grady (Arthur D. Little).
Candidate Techniques for Sampling and Analysis for Twenty-One Suspect
Carcinogens. Draft Report. U.S. Environmental Protection Agency.
Research Triangle Park, North Carolina. September 28, 1982.
2. Kogaczewska, T. Acrylonitrile Determination in Air. Med. Pr..
27(2):115-126, 1976. (In Polish). ~
3. Nagarova, V.I. and L.K. Nakrop. Determination of Acrybutrile in Air
M. Anal. K. Kach. Prod. Khum. Prom.. 5:28-29. 1Q7«. (In Russian).
4. Knodo, M. Sampling and Measurement of Organic Cyanogen Compounds.
Kankyo Hoken Reporti Environ. Health Rept.. 30:83-88, 1974. (in
Japanese).
5. Fasitta, V. and G. Ticciardello. Determination of Acetonitrile and
t??T ^Sfi1?/?1 tn^by ?aS Chromat°SraPhy- Ann. Inst. Super. Sanita..
13(1-2):245-248, 1977. (In Italian). !
6. Schultzl, 0., J.J. Prater, and S.R. Ruddell. Sampling and Analysis of
Emissions for Stationary Sources. I. Odor and Total Hydrocarbons. JAPCA,
£.3 \y) :y25—932, 1975.
7. Penton, Z. Measurement of Acrylonitrile in Industrial Air by Gas
Chromatography. Varian Instrument Appl.. 13(2):4-5, 1979.
8. Sawicki, E. Organic Solvent Vapors in Air. Analytical Method. Health
Lab. Sci., 12(4):394-402, 1975. ~
9. Gomez, C.R. and E.G. Linder. Quantitative Determination of Acrylonitrile
in Work Areas. Traub. Simp. Hyg. Ind.. 3:495-506, 1979. (In Spanish).
10. Marano, R.S., S.D. Levine and T.M. Harvey. Trace Determination of
Subnanogram Amounts of Acrylonitrile in Complex Matrices by Gas
Chromatography with a Nitrogen Selective Detector. Anal. Chem.. 50: (13),
1948—1950, 1978. ^—-^——_
11. Oomens, A.C. Experience With a Dual Detector Headspace Gas Chromatograph
for Acrylonitrile Analysis. Appl. Headspace Gas Chromatographv.. 1980.
pp. 111—116.
12. Taylor, D.G., coord. NIOSH Manual of Analytical Methods, Vol. 3 2nd
ed., 1977. pp. 5156-1 to 5156-8.
13.. Gagnum, Y.T., and J.C. Posner. Recovery of Acrylonitrile from Charcoal
Tubes at Low Levels. Am. Ind. Hyg. Assoc. J.. 40(10):923-925, 1979.
61
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14. Russell, J.W. Analysis of Air Pollutants Using Sampling Tubes and Gas
Cnromatography. Environ. Sci. Technol.. 9(13):1175-1178, 1975.
15. Parsons, J.S., and S. Mitzner. Gas Chromatographic Method for
Concentration and Analysis of Traces of Industrial Organic Pollutants in
Environmental Air and Stacks. Environ. Sci. Technol.. 9(12):1053-1058,
iy / •? •
16. Brown, R.H., and C.J. Purnell. Collection and Analysis of Trace Organic
Vapor Pollutants in Ambient Atmospheres. The Performance of Tenax-GC
Adsorbent Tube. J. Chromatogr.. 178(1):79-90, 1979.
17. Campbell, D.N., and R.H. Moore. The Quantitative Determination of
Acrylonitrile, Acrolein, Acetonitrile and Acetone in Workplace Air.
Am. Ind. Hyg. Assoc. J.. 40(10):904-909, 1979.
18. Schabel, K.H., and R. Casper. Headspace Gas Chromatography in Industrial
Hygiene. Appl. Headspace Gas Chromatogr.. 1980, pp. 32-40.
19. -Casper, R.H. Special Analytical Methods with Respect to Industrial
.'i- Hygiene. Annu. Meet. Proc.-Int. Inst. Symp. Rubber Prod., 18, Paper
'• " No; 6, 1977, pp. 15.
20. Jacobs, H., and R. Syrjola. The Use of Infrared Analyzers for Monitoring
Acrylonitrile. J. Am. Ind. Hyg. Assoc.. 39(2):161-165, 1978.
21. Syyrjola, R.J. Quantitative Analysis of Atmospheric Pollutants Using a
Microcomputer Controlled Single Beam Infrared Spectrometer. Envir.
Anal., 1977, pp. 111-125.
22. Satoh, S. Gas Chromatography-Mass Spectrometric Identification of
Organic Compounds and Determination of Acrylonitrile in the Air of the
Kawasaki Industrial Area. Koenshu-Iyo Masu Kenkvwkui.. 4s113-120, 1979.
23. Koosker, A.A.M. Measurement of Organic Gases in the Atmosphere.
PT-Procestech.. 34(7):409-415, 1979.
24. Harris, J.C., M.J. Hayes, P.L. Levins, and D.B. Lindsay, EPA/IERL-RTP
Procedures for Level 2 Sampling and Analysis of Organic Materials
EPA-600/7-79-033, U.S. Environmental Protection Agency, 1979. pp. 165.
25. Thrun, K.E., J.C. Harris, C.E. Rechsteiner, D.J. Sorling. Methods for
Level 2 Analysis by Organic Compound Category, EPA-600/7-81-029, U.S.
Environmental Protection Agency, Research Triangle Park, North Carolina.
March 1981. pp. 123-131.
62
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TECHNICAL REPORT DATA
(Please read Instructions on the reverse before completing)
1. REPORT NO.
EPA-450/4-84-007a
3. RECIPIENT'S ACCESSION NO.
4. TITLE AND SUBTITLE
LOCATING AND ESTIMATING AIR EMISSIONS FROM SOURCES OF
ACRYLONITRILE
5. REPORT DATE
March 1984
6. PERFORMING ORGANIZATION CODE
7. AUTHOR(S)
Radian Corporation
3024 Pickett Road, Durham, NC 27705
8. PERFORMING ORGANIZATION REPORT NO
9. PERFORMING ORGANIZATION NAME AND ADDRESS
1O. PROGRAM ELEMENT NO.
11. CONTRACT/GRANT NO.
12. SPONSORING AGENCY NAME AND ADDRESS
U. S. Environmental Protection Agency
Office Of Air Quality Planning And Standards
MD 14
Research Triangle, NC 27711
13. TYPE OF REPORT AND PERIOD COVERED
14. SPONSORING AGENCY CODE
15. SUPPLEMENTARY NOTES
EPA Project Officer: Thomas F. Lahre
16. ABSTRACT
To assist groups interested in inventorying air emissions, of-, various
potentially toxic substances, EPA is preparing a series of documents such
as this to compile available information on sources and emissions of these
substances. This document deals specifically with acrylonitrile. Its
intended audience includes Federal, State and local air pollution personnel
and others interested in locating potential emitters of acrylonitrile and
in making gross estimates of air emissions therefrom.
This document presents information on 1) the types of sources that may
emit acrylonitrile, 2) process variations and release points that may be
expected within these sources, and 3) available emissions information
indicating the potential for acrylonitrile release into the air from each
operation.
7.
KEY WORDS AND DOCUMENT ANALYSIS
DESCRIPTORS
b.lDENTIFIERS/OPEN ENDED TERMS
c. COSATI Field/Group
Acrylonitrile
Sources
Locating Sources of Emissions
Toxic Substances
8. DISTRIBUTION STATEMENT
EPA Form 2220—1 (Rev. 4—77) PREVIOUS EDITION is OBSOLETE
19. SECURITY CLASS (ThisReport)
21. NO. OF PAGES
68
20. SECURITY CLASS (This page)
22. PRICE
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