EPA-600/2-77-023p
February 1977
Environmental Protection Technology Series
                 INDUSTRIAL  PROCESS  PROFILES  FOR
                    ENVIRONMENTAL USE:  Chapter  16.
                             The Fluorocarbon-Hydrogen
                                          Floride  Industry
                                  Industrial Environmental Research Laboratory
                                       Office of Research and Development
                                      U.S. Environmental Protection Agency
                                               Cincinnati, Ohio  45268

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                RESEARCH REPORTING SERIES

Research reports of the Office of Research and Development, U.S. Environmental
Protection Agency,  have been grouped  into five series. These five broad
categories were established to facilitate further development and application of
environmental technology. Elimination of traditional grouping was consciously
planned to foster technology transfer and a maximum interface in related fields.
The five series are:

     1.    Environmental Health Effects Research
     2.    Environmental Protection Technology
     3.    Ecological Research
     4.    Environmental Monitoring
     5.    Socioeconomic Environmental Studies

This report has been  assigned  to the ENVIRONMENTAL PROTECTION
TECHNOLOGY series. This series describes research performed to develop and
demonstrate instrumentation, equipment, and methodology to repair or prevent
environmental degradation from point and non-point sources of pollution. This
work provides the new  or improved technology required for the control and
treatment of pollution sources to meet environmental quality standards.
This document is available to the public through the National Technical Informa-
tion Service, Springfield, Virginia 22161.

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                                            EPA-60U/2-77-023p
                                            February 1977
         INDUSTRIAL PROCESS PROFILES

             FOR ENVIRONMENTAL USE

                  CHAPTER 16

 THE FLUOROCARBON-HYDROGEN FLUORIDE INDUSTRY
                       by

             Dow Chemical  U.S.A.
              Michigan Division
              Midland, Michigan
           Contract No.  68-02-1329
               Project Officer
               Irvin A. Oefcoat
 Industrial Environmental Research Laboratory
Research Triangle Park,  North Carolina  27711
 INDUSTRIAL ENVIRONMENTAL RESEARCH LABORATORY
      OFFICE OF RESEARCH AND DEVELOPMENT
     U.S. ENVIRONMENTAL PROTECTION AGENCY
            CINCINNATI, OHIO  45268

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                                 DISCLAIMER

     This report has been reviewed by the Industrial Environmental Research
Laboratory - Cincinnati, U.S. Environmental Protection Agency, and approved
for publication.  Approval does not signify that the contents necessarily
reflect the views and policies of the U.S. Environmental Protection Agency,
nor does mention of trade names or commercial products constitute endorsement
or recommendation for use.
                                       ii

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                       TABLE OF CONTENTS
                          CHAPTER 16

                                                          Page

INDUSTRY DESCRIPTION	    1
    Raw Materials	    2
    Products	    3
    Companies 	    3
    Environmental Impact	    4
    Bibliography	    5

INDUSTRY ANALYSIS 	    6
    Fluorocarbon Production Processes 	    7
       Process No. 1. Liquid Phase Fluorination 	   11
       Process No. 2. Distillation from Liquid Phase
         Fluorination 	   15
       Process No. 3. Separation, Neutralization,  Drying
         of Products from Liquid Phase Fluorination ...   17
       Process No. 4. Vapor Phase Fluorination	21
       Process No. 5. Distillation from Vapor Phase
         Fluorination 	   25
       Process No. 6. Separation, Neutralization,
         Drying  of Products from Vapor Phase
         Fluorination 	   27
       Process No. 7. Electrochemical Fluorination. ...   30
       Process No, 8. Separation, Neutralization,  Drying
         of Products from Electrochemical Fluorination. .   34
       Process No. 9. Bromination of Fluorohydrocarbons .  37
       Process No. 10. Purification of Bromo-
         f luorocarbons	39
       Process No. 11. Pyrolysis of Chlorodifluoromethane  42
       Process No. 12. Pyrolysate Scrubber, Separator,
         Drier	44
                              111

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                TABLE OF CONTENTS (Continued^
                          CHAPTER 16
                                                           P^ge
       Process No. 13. Reductive Dechlorination of
         1,1,2-Trichlorotrifluoroethane 	   47
       Process No. 14. Separation and Purification of
         Products from Dechlorination of 1,1,2-Tri-
         chlorotrifluoroethane	49
       Process No. 15. Addition of Halogens to
         Perfluoroalkenes 	   52
       Process No. 16. Dimerization of Fluoroolefins. ...   54
       Process No. 17. Oxidation of Ch ;-r^fluoroolefins .  .   57
       Process No. 18. Production of Fluoroaxcrhols by
         Catalytic Hydrogenation	60
       Process No. 19. Preparation of Perfluoroalkyl
         Iodides	63
       Process No. 20. HF Addition to Acetylene	66
       Process No. 21. Separation and Purification of
         Fluorohydrocarbons from HF Addition	68
       Process No. 22. Chlorination of 1,1-Difluoroethane .   70
       Process No. 23. Dehydrochlorination of 1-Chloro-l,
         1-Difluoroethane 	   72
       Process No. 24. Production of Fluoroaromatic
         Compounds	75

    HF Production Processes 	   77
       Process No. 25. Mining of Fluorspar	80
       Process No. 26. Fluorspar Beneficiation	82
       Process No. 27. Agglomeration of Fluorspar	85
       Process No. 28. Hydrogen Fluoride Generation  ....   88
       Process No. 29. Hydrogen Fluoride Purification  ...   90

Appendix A - Raw Materials	93
Appendix B - Products and By-Products  	   95
Appendix C - Producers and Products	99

                               iv

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                        LIST OF FIGURES
                          CHAPTER 16

Figure                                                     Page

  1      Chemical Trees of Fluorocarbons .........    8

  2      Flowsheet for Production of Fluorocarbons by
           Liquid Phase Fluorination ...........    10
  3      Flowsheet for Production of Fluorocarbons By
           Vapor Phase Fluorination  ....  .......    20

  4      Flowsheet for the Production of Fluorocarbons
           By Electrochemical Fluorination ........    29

  5      Flowsheet for the Production of Bromofluoro-
           carbons ....................    36

  6      Flowsheet for the Pyrolysis of Chlorodi-
           fluoromethane  (FC-22) .............    41

  7      Flowsheet for the Reductive Dechlorination
           of 1,1,2-Trichlorotrifluoroethane .......    46

  8      Flowsheet for the Reactions of Fluoroolefins  .  .    51

  9      Flowsheet for the Oxidation of Chlorofluoro-
           olef ins ....................    56

  10      Flowsheet for the Production  of  Fluoroalcohols
           By Catalytic Hydrogenation  ..........    59

  11      Flowsheet for the Production  of  Perfluoro-
           Alkyl  Iodides .................    62
                                v

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                     LIST OF FIGURES (Continued)
                             CHAPTER 16

Figure

  12      Flowsheet for the Production of Fluorocarbons
            from Acetylene	   65

  13      Flowsheet for the Production of Fluoroaromatic
            Compounds	   74

  14      Flowsheet for the Production of Fluorspar  ....   79

  15      Flowsheet for the Production of Hydroge,
            Fluoride	   87
                                 VI

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                        LIST OF TABLES
                          CHAPTER 16

Table                                                     Page

  1      Process Descriptions  for Fluorocarbon
           Production..	     9

  2      Fluorocarbons Produced from Chlorocarbons  ...    22

  3      Input  Materials  and Products  from Electro-
           chemical  Fluorination	    31

  4      Typical Fluoroaromatic Compounds  and Input
           Materials	    75

  5      Processes  for HF Production	    78

 A-l      List of Raw Materials	    94

 B-l      List of Products and  By-Products	    96

 C-l      Company/Product List	   TOO

 C-2      Producers  of Fluorocarbons	   107

 C-3      Speciality Fluorochemicals List 	   103

 C-4      Producers  of Hydrogen Fluoride	   109
                                vii

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                        ACKNOWLEDGEMENTS
This chapter was prepared for EPA by Dow Chemical U.S.A.,
Michigan Division, Contract Projects Laboratory.  The con-
tribution of H. E. Doorenbus is gratefully acknowledged.

Helpful review comments from Marcus E. Hobbs and Edward A.
Tyczkowski were received and incorporated into this chapter,
                                 vm

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          FLUOROCARBONS - HYDROGEN FLUORIDE INDUSTRY

INDUSTRY DESCRIPTION
The materials of the fluorocarbon-hydrogen fluoride industry
consist primarily of chemically and thermally stable organo-
fluoro compounds which generally have nontoxic and nonflammable
qualities.  Most of the fluorocarbons are aliphatic compounds,
although recently there has been an increased interest in the
use of aromatic fluorocompounds.

The industry is composed of two major segments.  One segment is
the production of hydrogen fluoride for use as a raw material.
Another segment involves reacting the hydrogen fluoride with
raw materials to form the fluorocarbon products.

As shown on the process flowsheets, the raw materials of this
industry are primarily chlorocarbons, such as carbon tetrachloride
and chloroform, and anhydrous hydrogen fluoride.   The bulk of
the products from this industry is formed by allowing the chloro-
carbons and hydrogen fluoride to react in the liquid or vapor
phase or in an electrochemical cell; the fluorocarbons and hydrogen
chloride are the usual products.

Fifteen different companies manufacture fluorocarbons at 23
locations.  The manufacturing facilities vary in size from 50 kg
to 50 million kg per year.  An estimated 450 million kg of fluoro-
carbon compounds are produced annually in this industry.

The manufacturing locations of this industry are primarily
throughout the eastern, midwestern, and southern parts of the
U.S.  Many of these facilities are located near large  cities  and
most are  associated with  other industries at  that  same  location.

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The growth rate of the industry from 1963 to 1973 averaged nearly
9% per year.  A growth rate of 6.5% per year through 1977 was
projected in January 1973.  However, with increasing regulatory
pressure being exerted due to the possible health and safety
hazards of aerosol sprays, the current projected growth rate
is nearer 4-570 per year for the next five years.

The hydrogen fluoride (HF) used in the fluorocarbon industry is
generated to a large extent by the fluorocarbon producers pri-
marily for use in this industry, and approximately 45% of the
HF made in the U.S. is so used.  The HF industry is therefore
considered part of the fluorocarbon industry.  Another 3870 of
the HF is used in the aluminum industry for the production of
sodium aluminum fluoride, synthetic cryolite.  L sser amounts
are used for petroleum refining (5-6%), stainless rteel pickling
(3-4%) , uranium hexafluoride for nuclear fuels  (2-370) and other
minor applications.

Hydrogen fluoride (HF) is generated from the reaction between
sulfuric acid and acid grade (>97%) fluorspar (CaF2) and is  the
sole major product of this segment of the fluorocarbon industry.
The bulk of the hydrogen  fluoride is manufactured in the anhydrous
state.  If hydrofluoric acid is desired, the anhydrous material
is dissolved in water.  Ten different companies manufacture  hydro-
gen fluoride at 14 locations.  The manufacturing facilities  vary
in size from 4000 to 98,000 metric tons/year.   A total of 350,000
metric tons of hydrogen fluoride is produced annually from
1,220,000 metric tons of  fluorspar.

Raw Materials
The raw materials used for the production of hydrogen fluoride
are sulfuric acid and fluorspar (977o CaF2) .  Most of the  fluorspar
is mined in Mexico, Canada, and Europe; a small amount is mined
in Illinois and a few other states.  Fluorspar  usually occurs  as

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veins associated with limestone and sandstone, but is sometimes
associated with galena, sphalerite, calcite, or barite.

The major chlorocarbon raw materials used in this industry are
carbon tetrachloride, chloroform, and tetrachloroethylene -
products of the Industrial Organic Chemicals Industry.  Since
the reactions to produce the fluorocarbons are carried out in
closed systems, there is minimum danger from the chlorocarbons,
although some of these raw materials are toxic at high concen-
trations.  The basic raw materials are given in Appendix A.

Products
The industry began with the discovery that certain fluorocarbons
make excellent refrigerants.  The production of refrigerants and
aerosols currently constitutes approximately 75% of  total pro-
duction.  Other applications include solvents, blowing agents
for plastic foam (10%) , feedstocks for fluoropolymers  (570) and
fire extinguishants.  The two most important products of this
industry are trichlorofluoromethane and dichlorodifluoromethane
(fluorocarbon 11 and 12, respectively) with a combined production
of approximately 8070 of the total.  Excluded  from  examination  in
this study  are  fluorocarbon compounds marketed primarily as  phar-
maceutical  products, insecticides, surfactants,  explosives,  dyes
and  intermediates.  A  list  of products of  this  industry as  defined
is given in Appendix B.

Companies
The major  companies  in this industry  are  some  of the largest
chemical manufacturing companies  in  the  U.S.   These  include:

            Allied  Chemical  Corporation
            E.I.  du Pont de  Nemours &  Co.,  Inc.
            Kaiser  Aluminum  and  Chemical
            Penwalt Corporation

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            Racon,  Inc.
            Union Carbide Corporation

Appendix C gives a comprehensive company listing.

Environmental Impact
Most of the solid wastes from this industry are buried in the
ground.  The liquid products are usually scrubbed with water
or aqueous castic and dried with a desiccant.  The liquid wastes
can be neutralized and sent to a waste pond or stream.

A large quantity of hydrogen chloride by-product is normally
produced in the anhydrous gaseous state.  This i^ usually trans-
ferred to other plant uses.  Aqueous hydrochloric acid can also
be transferred and is rarely discarded.

Gaseous fluorocarbon emissions during manufacture and processing
are kept to a minimum by the industry.  However, the users of
many of these products do allow them to escape into the atmosphere
Measurements of the effect of these gases on our environment are
incomplete at present.

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Bibliography


(1)   Sittig, Marshall,  "Fluorinated  Hydrocarbons  and Polymers",
      Chemical Process Monograph,  No.  22,  Noyes  Development
      Corporation,  118 Mill  Road,  Park Ridge,  N.J.  07656,  1966.

(2)   Stull, D. R., Westrum,  E.  F., Jr.,  and Sinke,  G.  C., "The
      Chemical Thermodynamics of Organic  Compounds", John  Wiley
      and Sons, Inc., N.Y.,  1969.

(3)   CEH Manual  of Current  Indicators, Aug.  1974.

(4)   Chemical Marketing Reporter, Aug. 21,  1972.

(5)   Oil,  Paint,  and Drug Reporter,  March 16,  1970.

(6)   Chemical Horizons  Intelligence  File.

(7)   Chemical Week, Aug.  23, 1972, p. 14.

(8)   Literature  from Producing Companies of Fluorocarbons.

 (9)   MacMillan,  R. T.,  Fluorine,  In:  Mineral Facts and Problems,
      Bureau of Mines Bulletin  No.  650, United States Department
      of the Interior, Washington,  D.C.,  1970.

(10)   Wood, H. B., Fluorspar and Cryolite,  In:   Minerals Year
      Book, U.S.  Bureau  of Mines,  1971.

(11)   Kirk-Othmer, Encyclopedia of Chemical  Technology,  2nd
      Edition, Interscience  Publishers, New York,  1966,  Volume
      9,  pp. 506-847.

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INDUSTRY ANALYSIS

The data presented herein are taken primarily from the patent
literature.  Ancillary data are taken from recent trade publi-
cations, related books, and company brochures.  Much of the
thermal data on the heating or cooling requirements for processes
had to be calculated and/or estimated since this information was
not available in the literature.  Due to the present economic
climate and the potential fluorocarbon-ozone problem, actual
production data presented may vary from the reported values.

Other variations in production data may be caused by improvements
in processing techniques since the data were printed.  This, of
course, would be considered as a trade secret by the manufacturing
companies, and there is no open access to this information.
Research findings also play a role in the quantities of certain
fluorocarbons being manufactured.  For example, production of
aromatic fluorocarbons was recently begun due to new applications
or uses.  While production is very small now, it may continue to
grow and expand in the future.

The industry has been divided into two segments for analysis:
Fluorocarbon Production and HF Production.  Process flowsheets
and process descriptions are given for the processes involved
in these segments of the industry with operating parameters,
input materials, utilities, and waste streams defined for  each
process.

In general, manufacturing companies treat production techniques
as proprietary information and are reluctant  to divulge specific
information relating to methods used.  The process descriptions
contained in this section reflect data for selected reactions
considered typical for fluorocarbon production.  The reader must

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be aware that,  in some cases, the reaction specified may not be
the method of choice for commercial production of the indicated
fluorocarbon, or may be one of several alternate routes to the
product.

Producer/product data compiled from the 1976 Directory of Chemical
Producers differs somewhat from data received from producers and
from industry experts.  Limited attempts to resolve this inconsis-
tency were unsuccessful.  The data are presented as compiled, with
footnoes to indicate inconsistencies .

FLUQROCARBON PRODUCTION PROCESSES

The primary raw materials for the preparation of the principal
fluorocarbons are the chlorocarbons.  Certain fluorocarbons are
also prepared from acetylene.  Many of the incompletely fluorinated
products are subjected to additional chemical reactions (processes)
to give other useful produces.

Chemical trees shown in Figure 1 illustrate the sequences of
reactions in which fluorocarbons are prepared from hydrocarbon
raw materials.  Table 1 lists the process descriptions given for
this segment.

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              CC14 	> CFC13 + CF2C12 + CF3C1
  CBr2F2
        CF3CFC1-CF2C1   CF3»CFBr-CF2Br
                                               CF2Br-CF2Br
CC12=CC12 —> CF2C1-CFC12+CFC12-CFC12+CF2C1-CF2^1+CF3CF2C1+CF3CF3
                             CF2=CFC1
              CF3CC13 —-> CF3COC1 —> CF3COOH
                              CH3CHF2+CH2=CHF
                                CH3CC1F2   — > CH2=CF2
     Cl               Cl
CC12=C-C=CC12	> F3C-C=C-CF3 -> F3C-COOH 	> F3CI
                        Cl
             Cl
                                              F3C-CH?OH
                  F3C-C=C-CF-,   F.C-CF.-CF.-CF,
                        V
           FIGURE  1.    CHEMICAL TREES OF FLUOROCARBONS
                               8

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             Table  1.    PROCESS DESCRIPTIONS FOR
                    FLUOROCARBON PRODUCTION
 1.   Liquid Phase Fluorination
 2.   Distillation from Liquid Phase Fluorination
 3.   Separation,  Neutralization,  Drying of Products from
     Liquid Phase Fluorination
 4.   Vapor Phase  Fluorination
 5.   Distillation from Vapor Phase Fluorination
 6.   Separation,  Neutralization,  Drying of Products from Vapor
     Phase Fluorination
 7.   Electrochemical Fluorination
 8.   Separation,  Neutralization,  Drying of Products from
     Electrochemical Fluorination
 9.   Bromination of Fluorohydrocarbons
1O.   Purification of Bromofluorocarbons
11.   Pyrolysis of Chlorodifluoromethane
12.   Pyrolysate Scrubber, Separator, Drier
13.   Reductive Dechlorination of 1,1,2-Trichlorotrifluoroethane
14.   Separation and Purification of Products from Dechlorination
     of 1,1,2-Trichlorotrifluoroethane
15.   Addition of Halogens to Perfluoroalkenes
16.   Dimerization of Fluoroolefins
17.   Oxidation of Chlorofluoroolefins
18.   Production of Fluoroalcohols by Catalytic Hydrogenation
19.   Preparation of Perfluoroalkyl  Iodides
2O.   HF Addition to Acetylene
21.   Separation and Purification of Fluorohydrocarbons from
     HF Addition
22.   Chlorination of 1,1-Difluorbethane
23.   Dehydrochlorination of l-Chloro-l,l-difluoroethane
24.   Production of Fluoroaromatic Compounds

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               Heat
Refrig.
n
                    liquid Thase
                    Fluorlnation
            sbCl3
h-1
O
                                                          Heat
                                                                             [To other plant uses]
Heat
       Distillation from
         Liquid Phase
         Fluorination 2
                            Recycle
                           £hloro and
                           [chlorofluor
                             carbons
r
Cooling
Water
\ Sep.,Neut.,
— ^- of Prods, f
/ Liq.-Ph.Flu
/
^
^
f
1
Dry'g.
orln. 3
t
                         FIGURE 2.    FLOWSHEET FOR PRODUCTION OF FLUOROCARBONS  BY

                                             LIQUID  PHASE FLUORINATION

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FLUOROCARBON PRODUCTION                PROCESS NUMBER 1

                Liquid Phase Fluorination

1.  Function
    To convert chlorocarbons to fluorocarbons by means of flu-
    orination with anhydrous hydrogen fluoride together with a
    catalyst.  The reactor may be made of steel, various stain-
    less alloys, Monel or nickel clad steel.
    a.  Carbon tetrachloride is converted into dichlorodi-
        fluoromethane  (FC-12) and trichlorofluoromethane
        (FC-11).

    b.  Chloroform is converted into chlorodifluoromethane
        (FC-22) and  dichlorofluoromethane (FC-21).

    c.  Tetrachloroethylene and chlorine are converted
        into trichlorotrifluoroethane (FC-113), tetrach-
        lorodifluoroethane  (FC-112), and dichlorotetra-
        fluoroethane  (FC-114).

    d.  Hexachlorobutadiene is converted into 2,3-dichloro-
        hexafluorobutene-2.  Perfluorobutene-2, and perfluoro-
        butane are made  from 2,3-dichlorohexafluorobutene-2
        by  subsequent  and different reactions.

2.  Input Materials
    Assuming a production capabity of 68 million  kg of product
    per year, and a  production rate of one  kg of  product  per  kg
    of catalyst per  hour, the quantities of raw materials re-
    quired  for  (a) above are:
             CCi	   9798 kg/hr
             HF 4	   2077 kg/hr
                            11

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for (b)  above:
        CHC13  ---------   13066  kg/hr
        HF    ---------    2077  kg/hr
and for (c)  above:
        CC12=CC12  -----    7610  kg/hr
        HF    ---------    4500  kg/hr
        clz    ---------    3250  kg/hr
Since the process  can be operated to  prepare more of one prod-
uct than another,  the feed ratio of HF to chlorocarbon may
vary depending upon what product is desired.

The catalyst consists of 2885 kg SbCl5,  290 kg SbCl3 and 7938
kg CC13F.  The efficiency of HF utilization is estimated to be
9770 and that of CCU is  estimated to  be "j-98%.
Operating Parameters
Satisfactory operating conditions cover wide ranges.  The
pressures may vary from 0 to 35 kg/cm2 ,  the temperatures from
45-200°C, catalyst concentrations from 10 to 90 weight per
cent, and product take-off temperatures from -30° to +100°C.
A typical example uses CC1,, and HF, a pressure of 7 kg/cm ,  a
reactor temperature of 80°C, a catalyst concentration of 60
weight percent in CC13F (400 parts SbCls, 40 parts SbCl3>
660 parts CC13F), and a reflux condenser temperature set at
-5°C.  Under these conditions, the products will consist
primarily of CHI and CC12F2 (all CC14 and CC13F being returned
to the reactor) .   Increasing the reflux condenser temperature
to +5°C allows some of the CC13F to escape to form  a 9:1 ratio
of CC12F2 to CC13F.  An increase in pressure will allow an
increase in condenser temperatures without altering the pro-
duct composition.  Thus, a range of variables is possible with-
out a change in product composition.  In general, an increase
in temperature and pressure will result in an increase  in rate.
                       12

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    Based on a plant having a production capacity of 68 million
    kg of product per year, and a production rate of one kg of
    product per kg catalyst per hour,  the catalyst bed size is
    estimated to be 1 meter2 x 6 meters.
4.  Utilities
    The reactor is normally heated by steam to a temperature of
    80°C.  Assuming again a production capacity of 68 million kg
    of product per year and a production rate of one kg of product
    per kg of catalyst per hour, for conversions (a), (b),  and
    (c) above:
    (a)  Approximately 400,000 kcal of heat per hour are required.
    (b)       "        740,000  "
    (c)       "        280,000  "
5.  Waste Streams
    The reaction is carried out in a closed system--the only dis-
    charges to air or water would be due to leaks and spills.
    Estimated catalyst losses:  2 x 10 "* kg/kg product.  The waste
    catalyst can be disposed of by burial.

6.  EPA Source Classification Code

7,  References
    1)  Oilman, H., Ed,, "Organic Chemistry", Volume 1, John
        Wiley and Sores, New York, 1943, p. 949.

    2)  Groggins, P.H., "Unit Processes in Organic Syntheses",
        McGraw-Hill, New York,  1958, p. 294.

    3)  Stacey, M., Tatlow, J.  C., and Sharpe, A. G., Editors,
        "Advances in Fluorine Chemistry," Volume 2,  Butterworths,
        Washington, DC, 1961, pp 48-51.
                            13

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 4)   Stacey,  M.,  Tatlow,  J.  C.,  and Sharpe, A. G. ,  Editors,
     "Advances  in Fluorine Chemistry",  Vol. 3, Butterworths,
     Washington,  DC,  1963, pp 117-180.

 5)   Daudt,  H.W., and Youker, M.A.,  U.S. Patent 2,005,705  (1935).

 6)   Daudt,  H.W., and Youker, M.A.,  U.S. Patent 2,005,708  (1935).

 7)   Daudt,  H.W., and Youker, M.A.,  U.S. Patent 2,005,710  (1935).

 8)   Daudt,  H.W., and Youker, M.A.,  U.S. Patent 2,062,743  (1936).

 9)   Holt,  L.C.,  and Mattison, E.L., U.S. Patent 2,005,713 (1935)

10)   Benning, A.F.,  U.S.  Patent 2,450,414  U,<48) .

11)   Benning, A.F.,  U.S.  Patent 2,450,415  (1948).

12)   Benning, A.F.,  U.S.  Patent 2,478,362  (1949).
                         14

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FLUOROCARBON PRODUCTION             PROCESS NUMBER 2

     Distillation from Liquid Phase Fluorination

1.  Function
    To separate more volatile by-products from the feed and
    product materials and to return the catalyst to the fluor-
    ination step.  Since the by-product is anhydrous hydrogen
    chloride, steel or stainless steel alloys may be used.

2.  Input Materials
    Depending upon the product desired, anhydrous hydrogen
    chloride, chlorocarbons, chlorofluorocarbons, and hydrogen
    fluoride are present as the feed.  Also small traces of the
    antimony salts may be present in the feed.

    If one assumes that  an  average  of two chlorines per molecule
    are replaced by  fluorines,  then for a plant having a produc-
    tion capacity of 68  million kg  per year,  between 3600 and
    8000 kg/hr  of anhydrous HC1 would be formed, depending upon
    what product is  desired.

3.  Operating Parameters
    As indicated in  the  fluorination process, the higher the
    pressure, the higher the distillation temperature may be.
    The actual  temperature  and pressure used also depend upon
    what product(s)  is desired.  The temperature can thus be
    varied from -30°  to +100°C and  the pressures can be varied
    from 3 to 14 kg/cm2.

4.  Utilities
    The  temperature  at which the distillation is performed
    determines  the  type of cooling required.  When the  distil-
    lation  is  performed at temperatures below 20°C, conventional
                        15

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    refrigeration cooling is required.   Above 40°C,  water cooling
    will be adequate.  On the above  size plant,  approximately
    500 kcal/hr of heat must be withdrawn.

5.  Waste Streams
    No emissions should occur in this process.  All anhydrous HC1'
    is recovered and used in other plant processes.  Because this
    is a pressurized system, leaks may develop.

6.  EPA Source Classification Code
    3-01-011-01 BY-Product w/o SCRUB

7.,  References
    1)  Stacey, M.,  Tatlow,  J.  C., and Sharpe, A. G., Editors,
        "Advances in Fluorine Chemistry," Vol. 3, Btitterworths,
        Washington,  DC, 1963, pp 117-180.

    2)  Benning, A.  F., U.S. Patent 2,450,415 (1948).
                                16

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FLUOROCARBON PRODUCTION                     PROCESS NUMBER 3

            Separation, Neutralization, Drying of
           Products from Liquid Phase Fluor inat ion

1.  Function
    a.  To separate the crude products into the desired final
        products and recycle materials.
    b.  To neutralize any acidic materials that may be present
        in the final products,
    c.  To dry the final products prior to end use.
    The separation step is usually divided into two steps,
    distillation and decantation.  Steel or stainless steel
    materials of construction may be used.

2.  Input Materials
    Chlorocarbons , chlorof luorocarbons and anhydrous HF feed into
    this process.  The quantities of these materials used depend
    upon what product  is desired.  For example,  if one wishes to
    produce equal amounts of  CC12F2  and CC13F as products,  then
    CClif is fluorinated under  conditions  such that these two
    materials are produced  in  nearly equal amounts.   Along with
    this, a small amount  (~5%)  of unreacted CCI^ and HF also are
    fed.  This mixture of feed materials  is subjected to an azeo-
    tropic distillation, during which time the CC12F2 and HF are
    removed from  the  CC13F  and
    The azeotrope, CC1 F  and HF, is then separated further by
    decantation and the CC1 F  containing a trace of HF is washed,
    e.g., by aqueous caustic, then dried, e.g., by molecular
    sieves, silica gel, etc., and bottled.  Depending upon the end
                               17

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   use, an additional distillation may be performed.   The de-
   canted HF is recycled to the fluorination process step (proc-
   ess  1).

    If CC12F2 is the only product desired, the CClgF and CC14 are
   recycled back to the fluorination process.  If CC13F is also
   desired as  a product, it may be separated from CC14 by dis-
    tillation.  Neutralization and drying of CC13F is performed,
    as  in  the case of CC12F2.

    Assuming a  production capacity of 68 million kg of product per
    year and assuming  that  equal  productions of CC12F2 and CC13F
    are  desired,  about 4200 kg of each of these materials, along
   with 260 kg of  CC14 and 25 kg of HF,  per hour are fed into this
    process.

3.  Operating Parameters
   Again  assuming  that equal productions of CC12F2  and CC13F
    are  desired as  products,  the  separation by azeotropic distil-
    lation may  be performed under a variety of pressures and
    temperatures.   Since the pressure and temperature are directly
    related  to  each other,  more pressure will allow an increase
    in  temperature  to  be used and hence less condenser cooling
    required.   However, at  higher temperatures CC12F2 dissolves
    to  a greater extent in  HF and HF is also more soluble in
    CC12F2.  The conditions for separating this azeotrope by
    decantation will probably be chosen by the manufacturer based
    on  cooling  capacity, materials of construction,  etc.

4.  Utilities
    Steam requirements for  separation by  distillation  will vary
    depending upon  what product(s)  is desired.   Assuming a produc-
    tion of 4200 kg per hour of CCl^,  an estimated  170,000 kcal/hr
                              18

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    of  heat are required for the distillation.   Only a small
    quantity of heat is required for regeneration of the (molecular
    sieve)  drying agent.

5.   Waste Streams
    For neutralization of the <1% of the HF present in the CC12F2
    following decantation, aqueous caustic may be used.  Up to 20
    kg/hr of NaOH may be required for neutralization.   The spent
    caustic (NaF + NaOH) may be discharged to a pond and complete-
    ly neutralized.

6.   EPA Source Classification Code
    None established.

7.   References
    1)   Stacey, M., Tatlow, J. C., and Sharpe, A. G.,  Editors,
        "Advances  in Fluorine Chemistry," Vol. 3, Butterworths,
        Washington, DC, 1963, pp 117-180.
    2)   Benning, A. F., U.S. Patent 2,450,415 (1948).
                              19

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(* Metal"!
LFluorideJ
            Heat
  Vapor Phase
  Fluorination 4
                     Recyc1e
                     Chloro-
                     carbons
                                                   [To other plant uses]
Cooling
Hater
Heat

Uifl —
Distillation fron
Vapor Phase
Fluorination 5




ifei

Sep.,Neut.,Dry'g.
f\f DvrtHi i/" t c £ v*riri
j T r rOQ UC 1 5 7 rOm
Vapor PH. Fluor. 6



           FIGURE  3.   FLOWSHEET FOR  PRODUCTION OF FLUOROCARBONS BY

                               VAPOR PHASE FLUORINATION

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FLUOROCARBON PRODUCTION                       PROCESS NUMBER 4
                   Vapor Phase Fluorination
1.  Function
    To convert chlorocarbons  to  fluorocarbons by means of vapor
    phase fluorination with anhydrous hydrogen fluoride
    and  a catalyst.

    Any  of  a  number  of chlorocarbons is converted  into a number
    of fluorocarbons.  In  this process  (as opposed to the liquid
    phase fluorination process)  less control on the degree of
    fluorination is  possible; therefore,  a larger mixture of
    products  is  obtained.   In general, this process is more
    suitable  for producing the more highly fluorinated compounds.

    The  reactor  consists of a heated tube or series of tubes
    filled  with  a granular catalyst and fed by a vaporized mix-
    ture of the  chlorocarbon  and anhydrous hydrogen fluoride.
    A variety of metallic  fluorides may be used as catalysts.
    These may be in  a solid granular or supported  form.  The re-
    actor can be made of steel,  stainless steel, or clad or
    alloy steel.

 2.  Input Materials
    The  quantities and types  of  materials  fed  into this process
    vary considerably and  are dependent upon  the product(s)  de-
    sired.  The  normal mole ratio of HF to chlorocarbon  is  1.1
    to  1.5  and the efficiency of HF utilization  is usually  from
    90  to 10O%.
                               21

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   A representative  list  of  chlorocarbons  which can be converted
   into  fluorocarbons  is  given  below.

      Table 2.  FLUOROCARBONS PRODUCED FR011 CHLOROCARBONS

         Feed                  Products	
      CC14              CC13F, CC12F2, CC1F3, CF4
      CHC13             CHClgF, CHC1F2, CHF3
      CC12=CC12 + C12   CC12F-CC1F2, CC1F2-CC1F2, CC1F2-CF3
                          CF3-CF3
           0                  000
      CC13-C-CC13       CC1F2-C-CC1F2, CC1F2-C-CF3, CF3-C-CF3
      CBr4              CBrF3, CHF3, CBr2F2, CBr3F
      CH3C12            CH2F2, CH2C1F

    Assuming & production capacity of  10 million kg of product
    per  year,  and  assuming  that approximately equal amounts of
    CC12F2 and CC13F  are desired  from  CC14,  the quantities of
    raw  materials  required  are:
                  CC14	   1400 kg/hr
                  HF	    3OO kg/hr
    With this  ratio of feed,  the  following quantities of  products
    would probably be obtained:
                  CC12F2	    64O kg/hr
                  CC13F	    480 kg/hr
                  CC1F3	      13 kg/hr
                  HCi	.	    525 kg/hr

3.  Operating  Parameters
    The  temperature employed  will vary from  100°  to 5OO°C.
    The  fluorination  is usually carried out  at  about  atmospheric
    pressure (1 kg/cm2).  Typical catalysts which  may be  used are
                              22

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   chromium oxyfluoride,  chromium oxyfluoride  -  aluminum fluoride,
   A1F3,  ZrFij,  CrF3,  etc.  Depending upon what production  quantity is
   desired, the  size  of  the  reactor  will  vary.   A typical example
   is seen in  the  following:

   A total  of  2O8 g of CC14  and 36 g of HF was vaporized and
   passed through a 5 x 30 cm bed of 0.5 x 0.5 cm pellets of
   chromium oxyfluoride in a nickel reactor for 30 min.  at  550°C
   and a contact time of 6.6 sec.  The products consisted of 9.6%
   CC1F3, 40.9% CC12F2,  13.6% CC13F, and 5.9% CC14.   In general,
   at any one  temperature, a decrease in contact time produces
   smaller quantities of  the highly fluorinated materials  and an
    increase in temperature produces greater quantities of the
   highly fluorinated materials.

4. Utilities
   The reactor is heated by flue gas or by high pressure steam
    to a temperature of about 150°C.   Assuming a production  capac-
    ity of 10 million kg of product per year, a total of about 2
   million kcal of heat per hour is required.   In addition to
    this, about 450kWh of electrical energy are required.

5. Waste Streams
   Waste streams should be limited  to leaks and spills from this
   closed system  process.

6. EPA Source  Classification Code
   None established.

7. References
    1)  Stacey, M., Tatlow, J. C., and Sharpe, A. G., Editors,
        "Advances in Fluorine Chemistry," Vol. 3, Butterworths,
        Washington, DC, 1963, pp  117-180.
   2)  Ruh,  R. P. and Davis* R.  A.,  U.S. Patent  2,745,886  (1956).
                             23

-------
3)  Foulletier, L.,  and Dassaud, R., U.S. Patent  2,897,064  (1959).
4)  Davis, R. A., and Brcadworth, M. R. , U.S. Patent  3,002,934  (1961)
5)  Farbwerke Hoechst A.-G.,  Fr. Patent  1,343,392 (1963).
6)  Swamer, F. W., Fr. Patent 1,372,549  (1964).
                         24

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FLUOROCARBON PRODUCTION                       PROCESS NUMBER 5

                       Distillation from
                   Vapor Phase Fluorination

1.  Function
    To separate the products obtained from the vapor phase fluori-
    nation process.  The still may be made of steel, stainless
    steel, or nickel clad steel.

2.  Input Materials
    The feed to this process consists of anhydrous hydrogen chlo-
    ride, chlorofluorocarbons, fluorohydrocarbons, chlorocarbons,
    and small quantities of anhydrous hydrogen fluoride.  The
    products may be separated by low temperature fractional dis-
    tillation after separating out the anhydrous HC1.  However,
    certain fluorinated products may have a boiling point very
    close to that  of HC1.  In this case, the HC1 and fluorocarbon
    may be scrubbed with water, dissolving the HC1.  One of the
    by-products from this process  is frequently a 3O% HC1 solution.

    If conditions  are  adjusted during the fluorination step such
    that no fluorocarbons are formed which have the same boiling
    point as HC1,  the  HC1 may be first separated and the remain-
    ing fluorocarbons  separated as in the liquid phase fluorina-
    tion process (see  process 3).

3.  Operating Parameters
    If the process is  operated such that the anhydrous HC1  is  the
    only highly volatile product,  the operating conditions  may be
    the same as the distillation performed in  process  2.  However,
    if a volatile  fluorocarbon also is formed, then  the HC1 may
    be scrubbed with water and the volatile  (insoluble) fluoro-
    carbon recovered from the aqueous HC1.   In this  case, the
    distillation may be accomplished under less pressure,  i.e.,
    up to atmospheric  pressure.

                              25

-------
    Thus,  the pressure,  temperature,  and refrigeration
    required  for the distillation depend entirely  upon the
    product feed, the temperature, and the contact  time for
    fluorination.

4.  Utilities
    The quantity of refrigeration needed here is similar to that
    in process 2, assuming similar input materials.   Under the
    proper conditions, water cooling would be adequate.

5.  Waste Streams
    No waste streams are involved in the above distillation.  The
    scrubbed HC1 may be removed to other plant uses  as a 30% solu-
    tion.

6.  EPA Source Classification Code
    3-01-011-02 BY-PRODUCT w/SCRUB

7.  References
    1)  Stacey,   M. ,    Tatlow, J. C. , and Sharpe,  A. G. , Editors,
        "Advances in Fluorine Chemistry," Vol. 3, Butterworths,
        Washington, DC, 1963, pp 146-154.
    2)  Slesser, C., Editor, "Preparation, Properties, and Technology
        of Fluorine and Organic Fluoro Compounds," McGraw-Hill Book
        Company, Inc., New York, 1951, pp 427-454.
    3)  Ruh,  R.  P., and Davis, R. A.,  U.S. Patent 2,745,886 (1956).
                              26.

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FLUOROCARBON PRODUCTION                    PROCESS NUMBER 6

       Separation, Neutralization,  Drying of Products
                from Vapor Phase Fluorination
1.  Function
    To separate, neutralize, and dry all desired products  pre-
    pared in the vapor phase process.   Prior to this  process,  the
    HC1 and low boiling products were removed via distillation
    (see process J>).   The remaining fluorocarbons,  chlorofluoro-
    carbons, and fluorohydrocarbons along with small  quantities
    of HP are separated by distillation, neutralized  by scrubbing
    with aqueous caustic to eliminate the HF, and dried with
    molecular sieves, silica gel, etc.  The still can be made
    from steel, stainless steel, or similar materials.

2.  Input Materials
    The feed materials to this process vary considerably depending
    on what products are being made.  However, a typical example
    may be seen below:

    Assuming a production capacity of 10 million kg of product
    per year, and assuming that nearly equal amounts  of CC12F2
    and CC13F are desired, the quantities of input materials are:
                        CC12F2   650 kg/hr
                        CC13F    490 kg/hr
                        HF         3 kg/hr
3.  Operating Parameters
    High efficiency distillation columns may be used to separate
    the products from this process.  They can be operated under
    pressure, but  usually are operated at atmospheric conditions.
    However, for feeds  such as CC12F2 and CClsF, the same operating
                               27

-------
    conditions may be used as given in process J3..   For  other
    feeds, the distillation will be carried out  at  different
    temperatures.   The temperatures employed will be  dependent
    upon the boiling points of products being separated.

4.  Utilities
    Steam requirements for this  process will vary considerably
    depending upon what products are  being separated.   Assuming
    the production of 65O kg/hr  of  CC12F2  and 49O kg/hr of
    CC13F, an estimated 48,OOO kcal/hr of  heat  are required
    for the distillation.

5.  Waste Streams
    A small amount of aqueous NaF - NaOH will be  obtained from
    the caustic scrubbing of the fluorocarbons.   This  may amount
    to about 7 kg/hr for the production quantities given above.
    This can be completely neutralized and disposed  of by burial.

6-  EPA Source Classification Code
    None established.

7.  References
    1)   Stacey, M.,  Tatlow,  J. C.,  and Sharpe,  A. G.,  Editors,
        "Advances  in Fluorine Chemistry,"  Vol.  3, Butterworths,
        Washington,  DC, 1963,  pages 146-154.
    2)   Slesser, C.,  Editor,  "Preparation, Properties, and Technology
        of Fluorine and Organic  Fluoro Compounds," McGraw-Hill Book
        Company,  Inc., New York, 1951, pages 427-454.
    3)   Ruh,  R. P.,  and Davis, R. A.,  U.S. Patent 2,745,886  (1956).
                              28

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                                     fMetalllcl
                                     LFIuorldeJ
I
                                                   Refrig


Electrochemical
Fluorination 7
%

S3
VO
                                                                       Sep.,Neut..Dry'g.
                                                                       of Products from
                                                                       Elec.Chem.FTuor. 8
                        FIGURE 4.    FLOWSHEET FOR THE  PRODUCTION OF  FLUOROCARBONS BY

                                           ELECTROCHEMICAL FLUORINATION

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FLUOROCARBON PRODUCTION                           PROCESS NUMBER 7

                  Electrochemical  Fluorination

1.  Function
    To convert hydrocarbons and chlorocarbons into fluorocarbons.
    Many organic compounds containing ether,  carboxyl,  amine,  or
    other groups can be fluorinated by this process without
    destroying these groups.   Other fluorination processes do
    not permit this.

    The electrochemical cell usually consists of a single compart-
    ment cylindrical or rectangular metal vessel, commonly made
    of iron, steel, or nickel.  A condenser made of iron or copper
    is attached to the cover, and is operated in a manner to
    return the effluent hydrogen fluoride to the electrochemical
    cell while allowing the products to exit the cell.

    Products which boil at high temperatures are frequently drawn
    off the bottom of the cell through a valve.  (Most completely
    fluorinated species are insoluble in liquid HF.)

2.  Input Materials
    Feed to the cell consists of a large variety of hydrocarbons,
    chlorohydrocarbons, and organic materials containing  func-
    tional groups.  Typical feeds and products are listed in
    Table 3.
                              30

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         Table 3.   INPUT MATERIALS AND PRODUCTS FROM
                 ELECTROCHEMICAL FLUORINATION
       Feed
    Hexanes
    CH3-0-CH3
    CH3COF
    CH3S02F
    CH 2 C1 2
    CHC1=CC12
    (C,H9)3N
    (CH3CO)20
          Product
Perfluorohexanes
CHF2-0-CF3, CF3-OCF3, CHF2-0-CHF2
CF3COF
CF3S02F
CC12F2, CHC12F
CHC1F-CC12F
(C,F9)3N
CF3COF
    In addition to the organic materials, anhydrous liquid hydro-
    gen fluoride and usually  a metallic fluoride, e.g., sodium
    fluoride or lithium fluoride, are  added.

3-  Operating Parameters
    During electrolysis, anhydrous HF is added periodically to
    keep the cell full.  The optimum cell potential is below
    10 v and is usually around 5 v.  Normally, direct current
    is used, although alternating current is effective.  The
    current controls  the amount of fluorination that takes
    place in a given  time.  For any given cell the potential
    applied and the substrate concentration are the variables
    which determine current density.  Current densities usually
    range from 0.0008 to 0.02 amps/cm2.  Current efficiencies
    range from 60 to  90%.

    The temperature at which electrochemical  fluorinations are
    carried out usually ranges  from  -10  to +40°C, but most fre-
    quently it is aroung 0°C.  Normally  the fluorinations are
                              31

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    performed at atmospheric pressures, but higher pressures  are
    required when the temperature is above 40°C.

    Concentrations of the substrate may vary  from 1  to  1570.
    Normally the substrate is added continuously  at  the rate
    it  is  fluorinated.

    The optimum conditions for fluorination will  usually be
    chosen so that the best yields are obtained of the  desired
    products.  Yields vary considerably and are low  for many
    compounds.

    Cell sizes have been designed from 10 to  10,000  amps.  With
    all the ancillary equipment a cell 23 cm  by 8.5  cm, and hold-
    ing about 1 £. of solution, was rated at  20 amps.   It measured
    1.3 x  1.3 x 0.6 meters.  The size of the  cell will  obviously
    depend upon what quantities of product are desired.

4.  Utilities
    The major kind of energy required in  this  process is electri-
    cal and the amount will depend  upon the  degree of fluorina-
    tion,   as well as the quantity of  materials produced.  From
    0.4 to 0.6 g of fluorine are available  per amp hr.   Refriger-
    ation  is required for the condenser.   The  amount of cooling
    required will depend to a large degree  on  the  temperature at
    which  the cell is operated which,  in turn, depends upon what
    substrate is being fluorinated.   Because of the high energy
    demands, oh site power generation is  usually from oil or gas
    fired  turbogenerators.

5.  Waste Streams
    There  are almost no discharges  to the air, water, or ground
    in this process.   Any HF which escapes from the condenser  is
                               32

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    absorbed by NaF.  The NaF-HF may be heated to  drive off the
    HF and regenerate the NaF, or  it may  be  disposed of by burial

6.   EPA Source Classification  Code
    None established.

7.   References
    1)  Stacey, M., Tatlow, J. C., and Sharpe, A. G., Editors,
        "Advances in Fluorine Chemistry," Vol. 1, Butterworths,
        Washington, DC, I960, pages 129-165.
    2)  Simons, J. H., Editor, "Fluorine Chemistry," Vol. 1,
        pages 414-420, Vol. 2., pages 340-341, Academic Press,
        Inc. , New York QS50) .
    3)  Wolfe, J. K., U.S. Patent  2,806,817  (1957).
                                 33

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FLUOROCARBON PRODUCTION               PROCESS NUMBER 8
    Separationf Neutralization. Drying of Products
          from Electrochemical Fluorination
 1.  Function
    To separate, neutralize, and dry all desired products .pre-
    pared in the electrochemical fluorination process.  Because
    the products will contain compounds which vary considerably
    in their degree of fluorination, their separation may at
    times require high efficiency distillation columns.

 2.  Input Materials
    All products and by-products from the electrochemical fluor-
    ination (see process J7) are fed into this process.  When
    acid fluorides or  anhydrides  are the products, they are
    scrubbed with sodium fluoride to eliminate any HF.  Fluor-
    inated hydrocarbons, ethers, amines, etc.  are scrubbed
    with water or aqueous caustic and the wet products are dried
    with a desiccant.

 3.  Operating Parameters
    The products are usually cooled, compressed, and distilled
    under pressure; however, the degree of cooling and com-
    pressing required will depend largely on the product ob-
    tained since many of these are liquid under normal condi-
    tions.  Operating pressures may be as high as 20 kg/cm2  and
    temperatures as low as -25°C.

4.  Utilities
    It is estimated that between 1 and 2O kcal/mole of heat
    are required for the distillation of the products.   If
    refrigeration is used, 5-50 kcal/mole  of heat need to be
    withdrawn from the system.
                           34

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5.   Waste Streams
    A small amount (<10 g/kg product) of sodium fluoride-HF
    or aqueous NaF/NaCl will be discharged to a waste pond.
    Small amounts of fluorocarbons may be discharged to the
    air in the pressurized distillation step.

6.   EPA Source Classification Code
    None established.

7.   References
 1) Stacey, M. , Tatlow, J.  C. , and Sharpe, A. G. , Editors,
    "Advances  in Fluorine  Chemistry," Vol. 1, Butterworths,
    Washington, DC,  pages  129-165 (1960).

 2)' Simons, J. H., Editor,  "Fluorine  Chemistry," Vol.  1,
    Academic Press,  Inc.,  New York,  195O, pages 414-420,
    Vol. 2, pages 34O-341.

 3) Wolfe, J. K., U.S. Patent 2,806,817  (1957).
                           35

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Heat
      Vaporizer,
      Bromination
        Reactor	9
Refrig.


Purif. , Scrubber,
Drier for Bromo-
fluoro Carbons 10


   FIGURE  5.    FLOWSHEET FOR THE PRODUCTION  OF

                 BROMOFLUOROCARBONS

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FLUOROCARBON PRODUCTION          .             PROCESS NUMBER 9

               Bromination of Fluorohydrocarbons

 1.   Function
     To convert fluorohydrocarbons  to bromofluorocarbons.   In this
                                                ^ - \ •"•• • i
     process CHC1F2 (FC-22) is converted into CBrClF0;  CHF3 (FC-23)
     is converted into CBrF3 ; and CH2F2 (FC-32) is converted into
     CBr2F2.  The process is accomplished in a pyrex glass reactor
     through mixing and vaporizing  the feed and reacting the
     fluorohydrocarbons with the bromine vapor.   Monel or nickel
     tube reactors can be used in place of glass.

 2.   Input Materials
     The fluorohydrocarbon is mixed with bromine vapors at a ratio
     of from 25 to 45 percent by weight of the former to 75 to 55
     percent by weight of the latter.  Depending upon the conditions,
     it is possible to prepare several different products.  If the
     main product desired is CBrClF2, a conversion of about 55% is
     achievable.  Thus, from 150 kg. of CHC1F2,  82 kg. of CBrClF2 is
     prepared.

 3.   Operating Parameters
     The temperatures at which the reaction is performed may vary
     from 30O to 9OO°C.  Normal operation is performed from 650° to
     75O°C.  Atmospheric pressure is used.

 4.   Utilities
     Approximately 100 kcal. of heat are required per kg. of product.

 5.   Waste Streams
     There should be no waste streams in this process other than
     those occurring abnormally due  to leaks or spills.
                               37

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6.  EPA Source Classification Code
    None established.

7.  References
    Barnhart, W. S.,  U.S. Patent 2,731,505 (1956)

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FLUOROCARBON PRODUCTION                       PROCESS NUMBER 10

              Purification of Bromofluorocarbons

1.  Function
    The crude products from  the bromination of  the fluorohydro-
    carbons (see process No. 9) are purified by scrubbing
    out the by-product hydrogen bromide  (HBr) and any unreacted
    bromine.  The scrubbed products,  along with any unreacted
    starting material, are subsequently  dried with a desiccant.

2.  Input Materials
    Into this process are fed the  following materials together
    with their  estimated quantities (per kg. of feed).
                     HBr        0.27  kgr
                     Br2        0.006
                     CBrClF2   0.55
                     CBr2F2     0.06
                     CHC1F2     0.12
                     HC1        O.OO4
    The feed  is scrubbed with water (or  aqueous caustic)  to re-
    move the HBr and trace quantities of Br2 and HC1.   The  bromo-
    fluorocarbons and starting material  are passed  through  a des-
    iccant  (silica  gel, molecular  sieves, etc.) and  the dried
    products recovered.  These may be used as a mixture or  sep-
    arated  by distillation,  if necessary.

3.  Operating Parameters
    The gases are scrubbed with ambient  temperature  water and
    dried at  atmospheric pressure.  The  dried gases  are cooled
    to about -  5°C,  liquefied, and stored.
                               39

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4.  Utilities
    For a production plant having a capacity of 200 kg.  per day,
    it is estimated that 0.5 kg.  of scrubbing water is required
    and approximately 60 kcal.  of heat need to be withdrawn from
                    i
    the system per kg.  of product.

5.  Waste Streams
    Since the aqueous HBr is too valuable to be discarded,  it is
    usually  recycled to  recover  the bromine values or diverted to
    other plant uses.  Traces of HBr,  HCl,  and bromofluorocarbons
    may escape due  to pump  leaks,  etc.,  but in general no  major
    quantity of the products is  lost  to  air,  water, or ground.
6.  EPA Source Classification Code
    None established.

7.  References
    Barnhart, W. S.,  U.S. Patent 2,731,505  (1956).
                              40

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             Heat
                 1
                  Pyrolysis
                   Reactor
          Refrig.-
  Crude
PyroTysis
 Products
   Pyrolysate
   Scrubber,
Separator.Drier 12
FIGURE 6.   FLOWSHEET  FOR THE PYROLYSIS  OF CHLORODIFLUOROMETHANE  (FC-22)

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FLUOROCARBON PRODUCTION                         PROCESS NUMBER  11

              Pyrolysis of Chlorodifluoromethane

1.  Function
    To prepare tetrafluoroethylene (CF2 = CF2) and hexafluoropropylene
    (CF3-CF=CF2) from Chlorodifluoromethane  (CHC1F2)(FC-22).  Other
    fluorochemicals obtained in small amounts from  this process in-
    clude difluoromethane (CH2F2), trifluoromethane (CHF3),  chloro-
    trifluoromethane , hexafluoroethane, octafluorocyclobutane, and
    trifluoroethylene.  These latter fluorochemicals,  as  well as HC1,
    are by-products of the pyrolysis and are not made  commercially
    by this route.

    Several equipment designs have been employed  for the  above  process,
    In general, the combustion chamber can be made  of  ceramic or high
    temperature steel, and the reaction tube may be made  of sintered
    aluminum oxide or platinum.

2.  Input Materials
    Normally, Chlorodifluoromethane is the feed material  to this proc-
    ess.   However, other feed materials such as tetrafluoromethane,
    trifluoromethane, and octafluoropropane,  may also be  used in this
    process to produce the same major products.   In some  reactor de-
    signs, finely divided carbon is used as a quenching medium  to
    prevent further reaction of the tetrafluoroethylene.

3.  Operating Parameters
    The pyrolysis may be performed at 850-1300°C.   The pyrolysis prod-
    ucts are  rapidly cooled to about 500°C  to prevent further  re-
    action.  Pressures of 0.1 to 0.5 kg/cm2 are frequently used with
    preferred contact times of 0.1 to 0.001 seconds.  Usually the
    process is performed non-catalytically.
                              42

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4.  Utilities
    Heat for this pyrolytic process  may be provided by electricity or
    combustion gases.  Electric arcs or oxyhydrogen  torches have
    also been used.  The heat  or power  requirements  are entirely
    dependent upon  the quantity and  type of starting material  fed
    to  the process.  However,  it is  estimated  that about  20 kcaL
    of  heat per mole of chlorodifluoromethane are required.

 5.  Waste Streams
    Other than leaks or spills, there should be  no waste  streams
    from the above  process.

 6.  EPA Source Classification  Code
    None established.

 7.  References
    1)  Okamura, K., et al, U.S. Patent 3,221,070  (1965).
    2)  Benning, A. F., et al, U.S.  Patent 2,406,794 (1946).
    3)  Dennison,  J. T. et al, U.S.  Patent 2,852,574 (1958).
    4)  Scherer, 0., et al, U.S. Patent 2,994,723  (1961).
    5)  Farlow,  M.  W., U.S. Patent  2,709,182  (1955).
    6)  Downing, F. B., et al, U.S.  Patent 2,551,573 (1951).
                              43

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FLUOROCARBON PRODUCTION                      PROCESS NUMBER 12

            Pyrolysate Scrubber,  Separator,  Drier

1.  Function
    To separate into pure components  the  pyrolysate from chloro-
    difluoromethane (FC-22).   The two major  products,  tetrafluoro-
    ethylene (CF2=CF2) and hexafluoropropylene  (CF3-CF=CF2)  must
    be highly pure before these monomers  can be satisfactorily
    homo- or copolymerized.   Separation and  purification is usu-
    ally accomplished by a series of  scrubbing, distillation,  ad-
    sorption and desorption steps under super-atmospheric pressures.
    Stainless steel equipment is  adequate for this  process.

2.  Input Materials
    The feed into this process consists of all  the  products of the
    pyrolysis from process 11.  These usually consist of tetra-
    fluoroethylene,  hexafluoropropylene,  hydrogen chloride,  and the
    unreacted starting material,  chlorodifluoromethane.   The follow-
    ing may also be present in minor  amounts:  trifluoromethane,
    chlorotrifluoromethane,  hexafluoroethane, difluoromethane,
    dichlorodifluoromethane,  and  octafluorocyclobutane.   The con-
    version of chlorodifluoromethane  into tetrafluoroethylene is
    dependent upon the pressure under which  pyrolysis occurs.
    Normally,  the pressure is kept at about  0.40 kg/cm2, whereupon
    the conversion is about 30% and the yield of tetrafluoroethylene
    is about 90%.   Therefore  the  materials fed to this process based
    on the  kg of product obtained,  are approximately
                    chlorodifluoromethane   3.5  kg.
                    tetrafluoroethylene     1.0  kg.
                    hexafluoropropylene     0.03 kg.
                    hydrogen  chloride       0.7  kg.
                    minor products           0.02 kg.

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3-  Operating  Parameters
   Pressure:   0.3-16  kg/cm2
   Temperature:   -20°  to 0°C
   The mixture of products  obtained is  extremely difficult to sep-
   arate by distillation.   Cold methanol  dissolves  all  the products
   except  the tetrafluoroethylene and hexafluoropropylene.  The
   dissolved  materials are  later stripped from the  methanol and
   recycled or packaged.

4.  Utilities
   It  is estimated that  electrical power  for compressors  and refrig-
   eration amounts to  5  kWh/kg of product.   Heat input  (steam)  for
   distillation  processes is  estimated  to be about  5OO  kcal/kg.
   Water consumption is  estimated to be about 50O 4./kg of product.

5.  Waste Streams
   Small quantities of tar  may be formed  in the process which are
   discarded  (ground burial).   Due to the process pressures in-
   volved, fluorocarbon vapor leaks may occur occasionally.  The
   aqueous hydrochloric  acid  resulting from the scrubbing of the
   product may be transferred to other plant uses.  Drying agents
   (desiccants)  may be regenerated or discarded.

6.  EPA Source Classification  Code
   None established.

7.  References
   Okamura, K.,  et al, U.S. Patent 3,221,070
                              45

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Heat
Scrubber, Drier
Sep.Purif.of De-
ed! or in. Prods. 14
    Reductive
    hlorinator
     FIGURE 7.   FLOWSHEET FOR  THE REDUCTIVE DECHLORINATION

                   OF 1,1,2-TRICHLOROTRIFLUOROETHANE

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FLUOROCARBON PRODUCTION                          PROCESS NUMBER 13

 Reductive Dechlorination of 1. 1.2-Trichlorotrifluoroethane

1.  Function
    To prepare chlorotrifluoroethylene by reductive dechlorination
    of 1,1,2-trichlorotrifluoroethane (FC-113) , according to the
    following reaction:         u
                                H2
                     CF2C1-GFC12 •+ CF2=CFC1 +  2HC1.
    The vapor phase reaction is usually carried out at elevated temp-
    eratures in the presence of hydrogen and a catalyst.  In addition
    to the desired product, two by-products predominate.  The products
    are later separated in a separate process  (see process No. 14) .
    The reaction may also be conducted using zinc in ethanol, accord-
    ing to  :
            CCL2F-CC1F2     >  CC1F=CF2 + ZnCl2
2.  Input Materials
    Based on 1 mole  of product,  the  following  feed rates  are used:
    1,1,2-trichlorotrifluoroethane -  1.3 moles /min.
    Hydrogen gas  - 2.3 moles/min.

3.  Operating Parameters
    Temperature:   490 - 580°C
    Pressure:      1.O5 kg/cm2
    Flow rate:     1,1,2-Trichlorotrifluoroethane - 15 moles/min.
                   Hydrogen - 3 moles/min.
    Reactor size:  50 liters
    Catalyst:      Copper gauze, copper-cobalt on MgO, or MgF

4.  Utilities
    It  is estimated  that 15 kcal/mole of heat are required to carry
    out this reaction.  The energy may be supplied as gas or elec-
    tricity.
                             47

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5.   Waste Streams
    The products from the above reactor are separated in the next
    process.   Other than leaks or spills,  no waste streams should
    be emitted from this closed system process.   In the case of
    reaction with zinc in ethanol,  the ZnCl2 formed may present a
    disposal problem.

6.   EPA Source Classification Code
    None established.

7.   References
    Mantell,  R.  M.,  U.S. Patent 2,697,124  (1954).
                             48

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FLUOROCARBON PRODUCTION                      PROCESS NUMBER 14

Separation and Purification of Products from Dechlorination of
                1,1.2-Trichlorotrifluoroethane

1.  Function
    To separate chlorotrifluoroethylene, trifluoroethylene, vinyl-
    idene fluoride and hydrogen chloride and purify the monomers.
    A mixture of these materials along with the unreacted start-
    ing material from the reductive dechlorination step (see proc-
    ess 13).  are fed into this process.  The main product, chloro-
    trifluoroethylene, is later used in homo- and copolymerizations.
    The two by-products,trifluoroethylene and vinylidene fluoride,
    are not made commercially by this  process.   (See processes 2jO
    and 23).  These  materials are separated by fractional distil-
    lation and  the HC1  is  usually scrubbed out with water.  Stain-
    less  stell  materials may be used.

2.  Input Materials
    The feed to this process  is  the same as the product from the
    dechlorination process  (see  process 13), and consists of
    chlorotrifluoroethylene,  trifluoroethylene, vinylidene fluor-
    ide and HC1, along with the  unreacted 1,1,2-trichlorotri-
    fluoroethane and hydrogen.

3.  Operating Parameters
    Temperature:     0 to -20°C
    Pressure:        140 kg/cm2
    Flow rate:       approximately 15 moles/min.

4.  Utilities
    It is estimated  that 15 kcal/mole of heat need  to be  withdrawn
    from  the system by refrigeration.   Additionally,  it  is estimated
    that  5 kWh of  electricity are required for  compression of  the
    gases.  About  0.25 i. of  water per  mole of  product  is needed
    for scrubbing.
                              49

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5.  Waste  Streams
    For  every  mole  of  product,  about 2 moles of HC1 are formed.  When
    dissolved  in water,  this  aqueous acid can be transferred to other
    plant  uses.

6.  EPA  Source Classification Code
    3-O1-O11-02  BYPRODUCT W/SCRUB

7.  References
    Mantell, R.  M.,  U.S.  Patent 2,697,124 (1954).
                             50

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 Fluoro-
 olefin
                          or
                          '

                                _^. Cool ing
                                JX^ water
                                IT    A
                           Addition
                                    Hater
                     coz
— ,
            Heat
>

Dimerization
Reactor ] g


FIGURE  8.  FLOWSHEET  FOR THE  REACTIONS  OF FLUOROOLEFINS

-------
FLUOROCARBON PRODUCTION                       PROCESS NUMBER 15

           Addition of Halogens  to Perfluoroalkenes

1.  Function
    to prepare brdittlnated and chlorinated fluorocarbons by the chem-
    ical addition of bromine or  chlorine to a perfluoroolefin.  These
    exothermic reactions may be  performed in the vapor phase or, alter-
    natively, may be performed by bubbling the olefin into the liquid
    halogen.  The equation for the reaction is shown below.
                       R-CF=CF,  + X_  	> R-CF-CF,
                              22         xx2
                                     where X=Br,Cl.
    The reaction proceeds quite  cleanly  - with the formation of only
    the product and with little  or no by-products.  A glass or monel
    reactor is satisfactory.

2.  Input Materials
    A halogen and a perf luoroolef in are  the only feed materials.

3.  Operating Parameters
    If the perfluoroolefin is bubbled through the liquid halogen,
    the halogen must be cooled with water.  The reaction normally
    occurs at atmospheric pressure.   No catalyst is required.   If
    reacted  in the  vapor phase,  the  product is passed through  a
    cooling  condenser.

4.  Utilities
    Only cooling water  is required.   The amount of cooling  is
    dependent upon  the  rate of  input.  It is estimated to be from
    160 to 240 kcal/kg.  of  product,  depending upon which  product
    is made.
                             52

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5.   Waste Streams
    Traces of halogen gases may leave the reactor as an effluent.
    These may be scrubbed with water, which is sent to a waste
    disposal pond.

6.   EPA Source Classification Code
    None established.

7.   References
    1)  Ruff, 0., and Bretschneider, 0., Chem. Abstr. 27, 2131 (1933)
    2)  Lacher, J. R., et al., J. Amer. Chem. Soc., 71, 1330 (1949).
    3)  Patrick, C. R., "Advances in Fluorine Chemistry," Vol. 2,
        Stacey, M., Tatlow, J. C., and Sharpe, A. G., Editors,
        Butterworths, Washington, DC, 1961
                                53

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FLUOROCARBON PRODUCTION                       PROCESS NUMBER 16

                Dimerization of Fluoroolefins

1.  Function
    To prepare cyclic perfluoroalkanes by homodimerization of a per-
    fluoroalkene.  Tetrafluoroethylene is converted into perfluoro-
    cyclobutane.  This is an alternative process for the preparation
    of perfluorocyclobutane (see process 11).  This reaction is
    amenable to homo- and codimerizations of  other olefins as well.

2*  Input Materials
    For the preparation of octafluorocyclobutane, the material intro-
    duced in this process is tetrafluoroethylene along with an inhib-
    itor such as C02 (3).

3.  Operating Parameters
    The temperature is maintained at 150-200°C  and  the  pressure is
    usually 14-18 kg/cm2.  Under normal operating conditions,  the
    cyclic dimer is formed, with the unreacted  monomer  tetrafluoro-
    ethylene being recycled.

4.  Utilities
    It is estimated that approximately 2 kWh of electrical energy  are
    required for compressors.  Approximately 10 kcal/kg of heat energy
    are required.

5.  Waste Streams
    Other than leaks or spills, a small quantity of CO2 and  fluoro-
    carbons may be lost in this pressurized closed cycle  process.
                               54

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6.  EPA Source Classification Code
    None established.

7.  References
    1)  Banks, R. E., "Fluorocarbons and Their Derivatives," University
        Chemistry Series, MacDonald Technical and  Scientific,  London,
        1970, pp 7-69.
    2)  Wust, H. A., U.S. Patent  3,101,304  (1963).
    3)  Knunyants,  I. L. , et al..  USSR  Patent 173,733  (1965).
                               55

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Ul
                                                  I     te«- V.UUI I
                                              It   fiT""r
Chloro-
fluoro-
olefin
  Tri-
 fluoro
Acetic Aci
                               FIGURE 9.  FLOWSHEET FOR THE OXIDATION OF

                                            CHLOROFLUOROOLEFINS

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FLUOROCARBON PRODUCTION                          PROCESS NUMBER 17

               Oxidation of Chlorofluorooleflns

1.  Function
    To prepare trifluoroacetic acid via oxidation of a double bond
    in olefins.  This chemical reaction is a laboratory scale alter-
    native to the commercial electrochemical process for making tri-
    fluoroacetic acid.  The product of oxidation may be extracted
    and distilled, or the aqueous alkaline solution may be evaporated
    to dryness, then acidified, to recover the desired product.  Tri-
    fluoroacetic acid may also be prepared from 1,1,2-trichlorotri-
    fluoroethane (FC-113) by forming the isomer CF3CC12 which is then
    hydrolyzed to CF3COC1 by fuming sulfuric acid and then further
    hydrolyzed to the acid by water.

2.  Input Materials
    An alkaline oxidizing agent is usually used for the chemical ox-
    idation.  Frequently potassium permanganate along with a small
    amount of sodium or potassium hydroxide are used.  Potassium
    dichromate has also been used.  The fluoroolefin compound most
    frequently used is:
                              Cl
                          CF3-C=C-CF3
                                Cl

    although the octafluorobutene-2 has also been used.  The yields
    of trifluoroacetic acid are about 80-857o based on the moles of
    trifluoromethyl compound fed.  About two moles of KMnOi, are re-
    quired per mole of product.

3.  Operating Parameters
    Normally the organic olefin is added portionwise to the oxidizing
    agent in this batch process, but the reverse is also effective.
                              57

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    The solution is  maintained  at  80-100°C  during the oxidation which
    occurs at atmospheric pressure.   The  feed rate is dependent upon
    the rate of oxidation;  normally  from  1-10 moles/day are added.

A.   Utilities
    It is estimated  that 30 kcal of  heat  are needed per mole of
    product formed.   About 500  £ of  cooling water are required
    per mole of product.

5.   Waste Streams
    The by-product,  manganese dioxide (Mn02), can be recovered or
    sent to ground burial.   Aqueous  potassium chloride may be sent
    to a disposal pond.   Waste  from  the acid hydrolysis of CF3CC13
    would be mainly  spent sulfuric acid,  which could be neutralized
    and sent to pond or  sewer.

6.   EPA Source Classification Code
    None established.

7.   References
    1)  Babcock, J.  H.,  and Kischitz, A.  D., U.S. Patent 2,414,706
        (1947).

    2)  McBee, E. T., Wiseman,  P.  A., and Bachman, G. B., Ind. Eng.
        Chem., 39, 415 (1947).
                              58

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                                              Heat
"1
                                                   Catalytic
                                                  Hydrogenator
Ol
     rRefrig
	9
                   Fl uoro-
                   alcohol
                             FIGURE 10.  FLOWSHEET FOR THE PRODUCTION OF

                               FLUOROALCOHOLS  BY CATALYTIC HYDROGENATION

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FLUOROCARBON PRODUCTION                       PROCESS NUMBER 18

    Production of Fluoroalcohols by Catalytic Hydrogenation

1.  Function
    To prepare fluorinated alcohols by the catalytic reduction of
    ketones or fluorinated esters, according to following general
    reaction:
            S               cat.
        R-0-C-(CF2)nF + 2H2  -»•   ROM + HOCH2-(CF2)nF
    The pure fluorinated alcohol may be recovered by distillation.
    The reduction is frequently carried out in a steel bomb.  This
    process finds use in the preparation of hexafluoro-2-propanol,
    but, because of the relatively low yield, it is not normally
    used for preparation of 2,2,2-trifluoroethanol.

2.  Input Materials
    In addition to the ketone or ester and hydrogen gas,  a catalyst
    is required.  The composition of  the catalyst may involve pal-
    ladium, or platinum impregnated on alumina (1),  or it may in-
    volve a copper-chromium compound  (2).   Conversions  and yields
    vary with the pressure, temperature,  catalyst,  and compound used.

3.  Operating Parameters
    If the process is carried out in a pressure vessel (bomb), high
    pressure (35O-70O kg/cm2) is required.  If carried out under low
    pressure (<5 kg/cm2), conversions usually are lower.  Tempera-
    tures may vary from 5O-3OO°C.  The amount of catalyst may vary
    from 0.5-300% based on the weight of the ketone or ester.  In
    one example, 10O cm3 of Ru-Al203  catalyst (0.5% Ru) was charged
    into a 1.5 cm internal diameter fused alumina reactor 91 cm long
    which was heated over 76 cm of length in an electric furnace.
    The internal temperature was maintained at 265°C and a mixture
    of 183 g of 2,2,2-trifluoroethyl trifluoroacetate and 46 i. of
    hydrogen was passed through the reactor in a 5 hour period.  The
    residence time was approximately 15 seconds.  The exit  gases
                              60

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    were cooled in a dry ice-trap and the condensate was later
    fractionated into 45 g. of starting material and 40 g. of
    2,2,2-trifluoroethanol representing a 21% conversion.  The
    yield for the conversion of hexafluoroacetone to hexafluoro-
    2-propanol is >9O%.

4.  Utilities
    It is estimated that about 2O kcal of heat are required per
    mole (100 g.) of product formed.  Electrical heating is
    usually used.  Water (100 kg/kg) or refrigeration is required
    for condensation of the product.

5.  Waste Streams
    Excess hydrogen can be vented to the atmosphere.  The catalyst
    will need replacement after a period of time due to handling
    losses.  It is estimated that this will involve not more than
    1 g./kg of product.

6.  EPA Source Classification Code
    None assigned.

7.  References
    1)  Anello, L. G., and Cunningham, W. J., U.S. Patent 3,356,746
        (1967).
    2)  Case, L. C., and Yan, T-Y,    U.S. Patent 3,314,987  (1967).
                              61

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to
                                        SilverN
                                      Perfluoro-'
                                     Carboxylate
                                  FIGURE 11.  FLOWSHEET FOR  THE PRODUCTION OF

                                             PERFLUOROALKYL IODIDES

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FLUOROCARBON PRODUCTION                      PROCESS NUMBER 19

            Preparation of Perfluoroalkyl Iodides

1.  Function
    To convert perfluoroearbbxylic acids to perfluoroalkyl iodides.
    The batch reaction involves careful heating of the dry silver
    salt of a perfluorocarboxylic acid with iodine vapors according
    to the following general equation:
              Rf-COOAg + I2 	> RfI + C02 + Agl
    Any mono- or difunctional perfluorocarboxylic acid can be con-
    verted in this manner, including trifluoroacetic and perfluoro-
    heptanoic acids.  This Hunsdieker reaction is usually carried
    out in glass equipment on a small scale; steel should also be
    satisfactory.

2.  Input Materials
    Assuming a typical average yield of 90% of the perfluoroalkyl
    iodide from  the perfluorocarboxylic acid, input materials (per
    mole of product) consist of:
                 1.11 moles silver perfluorocarboxylate
                 1.44 moles of iodine (30% excess)
                 0.10-0.20 moles phosphorus pentoxide  (desiccant)

3.  Operating Parameters
    The reaction is carried out at atmospheric pressure  and at
    1OO-160°C.   A 3-Z. flask with adequate air and water-cooled
    condensers is adequate to prepare one mole of the  perfluoroalkyl
    iodide.

4.  Utilities
    It is estimated that about 2 kcal/mole of heat is  required,
    usually electrical energy, to carry out this  process.  About
                               63

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    10O 1. of cooling water per mole of product is needed.  An
    additional 5 kcal/mole of heat needs to be withdrawn from
    the product prior to packaging.

5.  Waste Streams
    A small amount of phosphoric acid (or anhydride) will be dis-
    charged from this process; the quantity depends upon the dryness
    of the feed.  This can be sent to a waste pond.  One mole of
    silver iodide is formed per mole of product.  This is recovered
    and recycled after appropriate treatment.  Carbon dioxide
    (1 mole/mole) is also evolved in the process.

6.  EPA Source Classification Code
    None established.

7.  References
    1)  Hudlicky, M., "Chemistry of Organic Fluorine Compounds,"
        The Macmillan Co., New York, 1962.
    2)  Crawford, G. H. ,  and Simons, J. H. , J. Amer. Chem.  Soc.,
        7£, 5737 (1953).
    3)  Banks, R. E., "Fluorocarbons and their Derivatives," Second
        Edition, MacDonald Technical and Scientific, London, 1970.
                              64

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Ul
                   ("Metallic!
                   [Fluoride]

                                                                              Dehydro-
                                                                             Chlorinator
                            FIGURE  12.   FLOWSHEET FOR THE PRODUCTION OF FLUOROCARBONS

                                                   FROM ACETYLENE

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FLUOROCARBON PRODUCTION                          PROCESS NUMBER 20

                   HF Addition to Acetylene

1.   Function
    To convert unsaturated hydrocarbons into  fluorohydrocarbons by
    the chemical addition of HF.  In this process, with  the  addition
    of HF, acetylene is converted to vinyl fluoride which  is then
    further reacted to 1,1-difluoroethane according to the following
    reaction:
                   CH=CH + HF * CH2=CHF + HF  ->  CH3CHF2
    The hydrofluorination reaction is usually carried out in  a vertical
    tubular reactor with HF and HC=CH feed inlets at the  base and
    product outlet at the top.  The tube is filled with a powdered
    catalyst.  The reactor may be made of stainless steel, Monel,
    or high nickel alloys.

2.  Input Materials
    A mole ratio of hydrogen fluoride to acetylene of between one
    and five  is usually used, and the reaction  is carried out in
    the vapor phase.  Approximately one volume  of powdered cat-
    alyst is  required per 100 volumes per minute of gas passing
    through the reactor. About half of the product is vinyl  fluo-
    ride and the other half is mainly 1,1-difluoroethane  (based  on
    acetylene).

3.  Operating Parameters
    The vaporized feed is fed into the reactor  at from 10  to 40OO
    ml. of acetylene per gram of catalyst per hour.  Preferably
    the feed  rate is approximately 10O volumes/volume of catalyst
    per hour.  Several catalysts are capable  of speeding up  the
    reaction—these are usually metal fluorides, e.g., aluminum
    fluoride.  The catalyst  is normally impregnated powdered
    alumina.  The feed rate  is highly dependent upon the activ-
                              66

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    ity of the catalyst.  The reaction is normally carried out
    at a temperature of 250  to 400°C  and at  a pressure of one
    atmosphere or higher.  It is  estimated that a reactor
    10 x 50 cm will produce  about 200 g  of product/hr.

4.  Utilities
    Assuming a production rate of 20O g of product/hr., about 2O
    kcal. of heat energy are needed to heat the reactor.  This is
    usually accomplished either by electric heaters or molten
    salt baths.

5.  Waste Streams
    The products from the reactor consisting of vinyl fluoride,
    1,1-difluoroethane, and HF,  along with small quantities of
    acetylene, are sent to the next process (process 21) for sep-
    aration.  Depending upon the conditions under which this
    process is operated, the lifetime and activity of  the cat-
    alyst is such that replacement is eventually needed.  This
    solid waste can be disposed of by burial.  The only other
    waste which should occur is due to leaks and spills.

6.  EPA Source Classification Code
    None established.

7.  References
    1)  Christoph, F. J., et  al. , U.S. Patent 3,178,484 (1965).

    2)  Petit, R., et  al., U.S. Patent 3,187,060  (1965).
    3)  Clark, J. W., U.S. Patent 2,626,963 (1953).
    4)  Swamer, F. W., U.S. Patent 2,830,101 (195S).
                              67

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FLUOROCARBON  PRODUCTION                        PROCESS  NUMBER  21

                 Separation  and Purification of
              Fluorohydrocarbons from HF Addition

 1.   Function
     To separate  the  crude products  and starting materials  from
     the HP-addition  process.  In  this process, vinyl  fluoride,
     1,1-difluoroethane  and  small  quantities of the  starting ma-
     terials,  acetylene  and  hydrogen fluoride, are separated by
     distillation under  pressures higher than atmospheric.   Mate-
     rials of  construction will  be Monel or nickel-clad  steel.

 2.   Input Materials
     An estimated 30% of the material entering this  process is
     vinyl fluoride,  another 35%  is 1,1-difluoroethane,  the re-
     mainder being hydrogen  fluoride (30%)  and acetylene  (2%).

3.   Operating Parameters
     The operation of this process is usually closely  integrated
     with the  preceding  process, and flow rates will be dependent
     upon the  rate of production from process 20.

     The gaseous  materials entering  this process are cooled and
     compressed.   After  cooling to about 0°C under pressures of
     up to 20  kg/cm2, the products are separated by  distillation.

     The desired  products may be passed through a scrubber  and
     drier, if necessary, before being sent to storage.   The
     hydrogen  fluoride and acetylene are recycled as feed to
     the HF-addition  process (process 2O).

4.   Utilities
     At  a  production  rate of 200 g of product/hr. , about  75 kcal/kg
                              68

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    of heat need to be withdrawn from the system.   The compressor
    will require approximately 5 kWh/kg of product.

5.   Waste Streams
    Small quantities of fluorohydrocarbons may be lost due to leaks
    and spills.  If the vinyl fluoride is scrubbed with 5% caustic
    (NaOH), small quantities of aqueous NaF may be sent to waste
    water.  The quantity of NaF formed is highly dependent upon the
    efficiency of the process at a particular location.

6.   EPA Source Classification Code
    None established.

7.   References
    1)  Houben-Weyl "Methoden der Organischen Chemie", Vol. 5,
        Part 3, Georg Thieme Verlag, Stuttgart, 1962, pp 8-14.
    2)  Air Reduction Co., Inc., British Patent 790,824 (1958).
                              69

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FLUOROCARBON PRODUCTION                       PROCESS NUMBER 22

              Chlorination of lrl-Difluoroethane

1.  Function
    To convert 1,1-difluoroethane into l-chloro-l,l-difluoroethane
    according to the following reaction:
               CHF2-CH3 + C12 	> CC1P2-CH3 + HC1
    The reaction may be performed in a stainless steel, nickel,
    or Monel reactor, usually tubular.

2.  Input Materials
    The feed materials are 1,1-difluoroethane and chlorine  usually
    two moles of the former to about one of the latter.  This  is
    arranged to ensure complete reaction of the chlorine.  A free-
    radical initiator (usually O.1-O.2% by weight, based on the
    amount of difluoroethane) is added in the feed.  The HC1 gas
    evolved may be forwarded to other plant uses or may be scrubbed
    out with water or aqueous sodium hydroxide.

3.  Operating Parameters
    The mixture of difluoroethane, chlorine and catalyst is pre-
    heated to 75-lOO°C, at which time free radical initiation
    begins.  An exothermic reaction ensues and the rate of feed
    is such that the subsequent reaction temperature is maintained
    between ISO and 2OO°C.  Pressures of about 27-38 kg/cm2 are
    normally used.  The preferred residence time  is from 2 to  8
    seconds.  The catalyst normally used is azo-bis-isobutyroni-
    trile; however, any catalyst capable of forming free radicals
    above room temperature should function as an  initiator.

4.  Utilities
    Although the chlorination reactor can be cooled externally by

                               70

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    water,  it normally is not.  No other utilities are usually
    involved.

5.  Waste Streams
    If aqueous caustic is used to scrub the HC1 by-product, the
    waste stream will consist of aqueous NaCl.  If the gaseous
    by-product is desired in other plant uses, it can be trans-
    ferred as such.

6.  EPA Source Classification Code
    None established

7.  References
    Wolf, H. 0., U.S. Patent 3,047,642  (1962).
                                71

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FLUOROCARBON PRODUCTION                      PROCESS NUMBER 23

      Dehydrochlorination of 1-Chloro-l.l-Difluoroethane

1.  Function
    To prepare vinylidene fluoride (CF2=CH2) by the pyrolytic re-
    moval of hydrogen chloride from l-chloro-l,l-difluoroethane
    according to the following reaction:
                    CC1F2-CH3 	> CF2=CH2 + HC1
    This vapor phase reaction is usually carried out, in the
    absence of a catalyst, in a stainless steel or nickel heated
    tube.

2.  Input Materials
    Normally, l-chloro-l,l-difluoroethane is the only feed material
    to this process.  The process gives high conversions and essen-
    tially quantitative yields, i.e., one mole of feed produces one
    mole of product.  Water, or aqueous caustic (NaOH) may be used
    to scrub out the hydrogen chloride eliminated during the reaction.
    This requires 1 mole of NaOH per mole of product.

3.  Operating Parameters
    The optimum temperatures for dehydrohalogenation are 7OO-850°C.
    The reaction is normally performed at atmospheric pressure or
    slightly lower, with  reaction times of less than 1 second and
    at space velocities of  100 to 500 per hour.

4.  Utilities
    This endotheraiic reaction requires about 20 kcal/mole of feed.
    The reactor tube can be heated with gas or  electricity.    If
    water is used to scrub the products, 1  liter of water is re-
    quired for every 10 moles of product.   Compression  and  refrig-
    eration are needed  to package the vinylidene fluoride.  An
                               72

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    estimated 1 kWh/mole is required.

5.   Waste Streams
    If water is used for scrubbing, the aqueous (35%) hydrochloric
    acid can be transferred to other plant uses.  If 10% aqueous
    caustic is used, the aqueous salt (NaCl) solution could be
    disposed of in a waste pond.  One liter of salt solution will
    be formed for every 2.5 liters of vinylidene fluoride formed.

6.   EPA Source Classification Code
    3-O1-O11-02  BYPRODUCT W/SCRUB
         )
7.   References
    1)  Scherer, 0., et al. U.S. Patent 3,183,277 (1965).
    2)  Feasley, C. F., et al. U.S. Patent 2,627,529 (1953).
    3)  Miller, C. B., U.S. Patent 2,628,989 (1953).
                               73

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                  Heafc
                            Cooling
                            water
                                         Fluoro
                                        aromatic
                                        Compounds
 Chloro-
aromatic
Compound
  Aromatic
Fluorination
FIGURE 13.   FLOWSHEET  FOR THE PRODUCTION OF

         FLUOROAROMATIC COMPOUNDS

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FLUOROCARBON PRODUCTION
                  PROCESS NUMBER 24
            Production of Fluoroaromatic Compounds

1.  Function
    To prepare fluorine-substituted benzenes, pyridines, pyrimidines,
    etc. , by the action of a metal fluoride on  the  corresponding
    chlorine-substituted benzene, etc.  This rather recently  de-
    veloped process  is being used to make  limited amounts  of  the
    fluoroaromatic compounds.   Certain  fluoroaromatics  can be
    made in glass equipment  in  a solvent;  others are more  commonly
    made neat  (without solvent) in pressurized  stainless steel  or
    Monel vessels.   Aromatic fluorine compounds have historically
    been prepared by diazotization of amines in HF  alone or with
    complexing agents such as BF3 to form  diazonium salts  which
    decompose  to aromatic  fluorine compounds

2.  Input Materials
    The following are typical of input materials together with
    products obtained in this batch  process.

  Table 4.  TYPICAL FLUOROAROMATIC COMPOUNDS AND INPUT  MATERIALS
        Feed Material
  2-Chloropyridine
  2,6-Dichloropyridine
  2,4,6-Trichloropyrimidine
  Nitrobenzene
  1,3,5-Trichlorobenzene
      Product (% yield)
2-Fluoropyridine (74)
2,6-Difluoropyridine (8O)
2,4,6-Trifluoropyrimidine  (90)
+Chlorodifluoropyrimidine  (9)
+Dichlorofluoropyrimidine  (0.9)
3-Fluoronitrobenzene
+2-Fluoroni trobenzene
44-Fluoronitrobenzene
3,5-Dichlorofluorobenzene  (54.5)
3,5-Difluorochlorobenzene  (47.7)
1,3,5-Trifluorobenzene (56.2)
                               75

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    CsF or KF may be used as the fluorinating agent  depending
    upon the substrate being fluorinated.   Usually an 8-10% excess
    of the fluorinating agent is used.

3.  Operating Parameters
    When the process is performed in a solvent,  the reaction is
    carried out at about 100-200*0 at atmospheric pressure.  When
    performed neat, the temperatures are about 30O-40O°C and the
    pressures 20-25 kg/cm2.

4.  Utilities
    It is estimated that the heat required per mole of product is
    10 kcal.  This may be in the form of electrical or gas heat.
    About 10O 4» of cooling water will be required per mole of
    product.

5.  Waste Streams
    For each mole  of  chlorine  atoms replaced,  there will be one
    mole of KC1  formed.  This  can  be discharged to a waste pond.
    The solvent, when used,  can be recycled or  discharged to a
    waste pond.

6.  EPA Source Classification Code
    None assigned.

7.  References
    1)  Boudakian, M.  M., J. Hetero. Chem., 5, 683 (1968).
    2)  Boudakian, M.  M., U.S.  Patent 3,296,269  (1967).
    3)  Boudakian, M.  M., U.S.  Patent 3,280,124  (1966).
    4)  Boudakian, M.  M., and Kaufman, C. W., U.S. Patent  3,314,955  (1967!
    5)  Shiley, R. H., Dickerson, D. R., and Finger, G. C., J.
        Fluorine Chem., 2,  19 (1972); I, 415 (1971); 4, 111 (1974);
        3,  113 (1973).
                              76

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    6)   Pavlath,  A.E.  and Leffler, A.L.,  "Aromatic Fluorine
        Compounds",  ACS monograph No. 155, Reinhold, New York,
        1962.

HF PRODUCTION PROCESSES

Hydrogen fluoride, important as the principal fluorinating agent,
is obtained by treating acid grade fluorspar (CaF2) with sulfuric
acid.  The impure fluorspar is mined and beneficiated to obtain
material of adequate purity for use in producing fluorocarbons.
Process flowsheets and process descriptions for this segment of
the industry follow.  Table 5 lists the processes involved in the
production of HF.
                              77

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Table 5.   PROCESSES FOR HF PRODUCTION









 25.   Mining of Fluorspar



 26.   Fluorspar Beneficiation



 27.   Agglomeration of Fluorspar



 28.   Hydrogen Fluoride Generation



 29.   Hydrogen Fluoride Purification
                  78

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                                   Heat
Mining
                   Ferrosilicon
Flotation
Agents
    FIGURE 14.   FLOWSHEET FOR  THE PRODUCTION OF  FLUORSPAR

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HF PRODUCTION                          PROCESS NUMBER 25

                  Mining of Fluorspar

 1.  Function
    To obtain the mineral from the solid ore deposits found in
    beds or veins in the earth.  The mining is done by metal
    mining practices, usually by top-slicing, cut-and-fill, and
    shrinkage and open stoppage.  Bedded deposits are usually
    worked by the room-and-pillar system.  Mining is done by
    shafts, drifts, and open cuts.

 2.  Input Materials
    Essentially none are required other  than the utilities and
    services required to support  the personnel  and equipment.

 3.  Operating Parameters
    Mines range in size from small operations with mostly hand
    operated equipment to large operations using extensively
    mechanized equipment.

 4.  Utilities
    Large quantities of air are required to support personnel
    and mechanized equipment.  Small quantities of electricity
    are used for motors, lights, etc.,  but no large quantities
    are required in mining fluorspar.   Amounts of water used
    will vary considerably from mine to mine, depending upon
    the operations involved.

 5.  Waste Streams
    Airborne fugitive dust of the  same  composition as the ore
    being mined is emitted in mining.   Water from subsurface
    mining operations is usually contaminated with finely
    crushed rock as well as with oil, hydraulic fluid, gasoline,
    and other materials commonly used in underground operations.
                          80

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6.  EPA Source Classification
    None established.

7.  Bibliography
    1)  Kirk-Othmer, Encyclopedia of Chemical Technology,
    John Wiley & Sons,  Inc., New York,  1966.
    2)  Malhotra, Ramesh,  Illinois Minerals Note  58,  Illinois
    State Geological Survey, Urbana,  Illinois, Oct. 1974.
                            81

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HF PRODUCTION                          PROCESS NUMBER 26

                Fluorspar Beneficiation

1.  Function
    To remove rocks and clays from the desired ore so that the
    crude ore may be purified.   This is usually accomplished
    by one or more of the following procedures, depending upon
    the purity of the mined fluorspar.
      (a)  Washing.   The raw ore is subjected to water sprays
           as it travels up the log pulper, to remove the
           associated clays.
      (b)  Heavy Media Separation.   The ore minerals are sep-
           arated from waste in a cone containing a suspension
           of finely ground ferrosilicon.   The ratio of ferro-
           silicon to water is  adjusted to give the suspension
           a specific gravity of about 2.6 at the top of the
           cone and about 2.9 at the bottom.   Crude ore is
           introduced at the top of the cone.  Heavy minerals,
           such as fluorspar and metal sulfides, and sink are
           recovered at the bottom of the  cone.  Light minerals
           float and are carried away with the overflow.  Ferro-
           silicon is recovered magnetically and returned to the
           process.
      (c)  Crushing and Screening.   The ore is fed through a
           crushing system for  reduction to the desired fine-
           ness.   Metallurgical grades require sizes between
           0.95 and 3.8 cm.   If the raw ore is of metallurgical
           grade,  it is crushed and screened to the proper size
           with no previous refinement. To produce acid grade
           fluorspar,  the crushed ore is fed to a ball mill
           which reduces the size to between 35 and 200 mesh.
      (d)   Flotation.   Further  purification is achieved by

                          82

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            treating the ore minerals in flotation units by use
            of agitated water baths to which are added frothing
            agents and flotation reagents  to  selectively coat
            the minerals.  The sequence of reagents and flota-
            tion procedures varies according to the composition
            of the ore and preferences of the mill operator.
            Typical reagents are xanthates, acids, or sulfates.
       (e)  Filter and Drier.  The "pulp" from the flotation
            cells usually contains from 20 to 40 percent solids.
            The concentration is increased to about 6O% solids
            in a thickener and the resultant mixture filtered.
            The filter cake is further dried to less than 0.5
            percent water in a rotary drier at about 25O°C.
       (f)  Grinding.  The fluorspar is ground to a minus 325
            mesh after which it is transported to storage bins
            or enclosed hopper cars.

 2.   Input Materials
     The primary feed to this process is the raw ore as mined
     from the ground.  Water is required in washing the crude
     ore, in heavy media separation, and in the flotation
     steps.   The quantity of water required will depend upon
     how many of these steps are used in the beneficiation
     process.   It also will depend upon the purity of the
     fluorspar as mined.   Small quantities of flotation agents
     are also required.

3.   Operating Parameters
     The bulk of the operations is  carried out at ambient
     temperature and pressure.   However, steam is required
     to keep the flotation cells at about 38°C.

4.   Utilities
     Small quantities of  steam are required as indicated above.
                           83

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    Quantities  of  electricity  are  required to operate the var-
    ious motors, pumps,  etc.   It  is  estimated that from 10 to
    50 kWh of electrical energy is required per metric ton of
    product.  Oil  or gas fired driers  are required.   This is
    estimated to require 5O,OOO kcal per metric ton.   An esti-
    mated 8,000 -  10,000 liters of water are required per
    metric ton  of  fluorspar.

5.  Waste Streams
    Aqueous effluents from washing and separation contain
    suspended solids which are usually sent to settling ponds.
    Tailings from  the flotation operation contain both solids
    and the flotation agents.   The latter materials are not
    necessarily toxic but cause excessive growth of algae and
    bacteria.  Air emissions  in the  form of dust may occur;
    however, these are usually kept  to a minimum since the ore
    is usually maintained in  a wet condition.  Drying and
    grinding of the purified  ore  present  particle emission
    problems as well as aqueous and  flotation agent emissions.

6.  EPA Source  Classification Code
    None established.
7.  References
      1)  Kirk-Othmer, Encyclopedia of Chemical Technology,
      New York, John Wiley & Sons, Inc., 1966.
      2)  West, L.  and R. R. Walden, Milling Kentucky Fluorspar
      Tailings,  Mining Engineering, 542-544, May 1954.
      3)  Maier, F.  J. and E. Bellack, Fluorspar for Fluorida-
      tion,  Journal  of the American Water Works Association,
      January 1957.
                          34

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HF PRODUCTION                           PROCESS NUMBER  27

               Agglomeration of  Fluorspar

 1.  Function
    To  recover fine  grained flotation concentrates of metal-
    lurgical  quality and to convert  them into weatherproof
    dust-free pellets.   The dry  powder is mixed with a  bind-
    er  solution,  pelletized, and dried.  The pellets with-
    stand  outdoor exposure, including freezing and thawing
    and show  less dusting than natural gravel spar when ex-
    posed  to  thermal shock in the steel furnace.

 2.   Input  Materials
    Feed to this process consists of metallurgical grade
    fluorspar fines  in dry  form along with a binder solution
    of  sodium silicate and  an undisclosed additive.   The
    mass is pelletized in a 2.44-meter diameter rotating disc-
    type pelletizer, and the "green" pellets are fed into a
    long Porbeck baking oven where they are dried.

 3.  Operating Parameters
    The "green"  pellets are subjected to temperatures of 370-
    40O°C  for 20-30  minutes.

 4.  Utilities
    An  estimated 25,OOO kcal of  heat (oil or  gas  fired) per
    metric ton  of finished metallurgical grade pellets  is
    required.  Approximately 5-10 kWh of electricity are re-
    quired/metric ton.

 5.  Waste  Streams
    The main  emission source in  this operation is from  the
    baking oven  and  consists of  vapors from the binder
    solution.
                            85

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6.  EPA Source Classification
    None established

7.  References
      1) Hall, W. E.,  and Heyl, A. V., Economic Geology, 63,
         [6], 655 (1968).
      2) Maier, F. J.,  and Bellack, E., Fluorspar for Fluori-
         dation.  Journal of the American Water Works Associ-
         ation, 49,  41  (1957).
                       86

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00
                                Heat—-i
                                  HF Generator
                                     (kiln)    28
  HF
Purifier  2g
                       FIGURE  15.   FLOWSHEET FOR  THE PRODUCTION OF HYDROGEN FLUORIDE

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HF PRODUCTION                                 PROCESS NUMBER 28

                 Hydrogen Fluoride Generation

1.  Function
    To convert the mineral fluorspar (CaF2) into hydrogen fluoride
    (HF).  Finely ground acid grade fluorspar (? 97% CaF2)  is
    treated with concentrated sulfuric acid in a heated rotating
    steel kiln.  The product is formed according to the following
    reaction:
             CaF2 + H2S04 	> CaS04 + 2 HF
    The  anhydrous HF product is collected  as a gas and later dis-
    tilled to remove a small variety of foreign substances, e.g.,
    compounds of silicon and sulfur (see process 29).

 2.  Input Materials
    In  the manufacture of hydrogen fluoride, about 2.4 metric
    tons of finely ground acid grade fluorspar and 2.7 metric
    tons of commercial 96-98% sulfuric acid (5-10% excess)  are
    used per metric ton of HF produced.  Small quantities  of
    oleum are used to keep the concentration of H2S04  at  the
    96-98% level.

3.  Operating Parameters
    Since the reaction between sulfuric acid and  fluorspar is
    endothermic, heat is usually  supplied  externally  by  direct
    fire to the rotary kiln.  The reaction temperature is kept
    at  200to250°C.  Under these  conditions,  the  reaction time
    is  30 to 60 minutes.  A kiln 2 m x 4 m  should  produce about
    20O  kg. of hydrogen fluoride  per hour. The overall  yield
    of HF is about 90% based on fluorspar; and  80% based on
    H2S04.
                               88

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4.  Utilities
    Assuming a production rate of 2OO kg. of HF per hour, an
    estimated 12O,OOO kcal./hr. of heat  are required.

5.  Waste Streams
    The by-product from  the HF production is calcium sulfate
    (CaS04).  This is removed from the rotating kiln, at the
    end opposite the feed, via an air-lock screw drive and
    fed into water.  This by-product can be neutralized with
    lime and is frequently discarded (ground burial) although
    it can be sold as gypsum or used in  the manufacture of
    cements.  Assuming a production rate of 200 kg./hr. of HF,
    about 775 kg./hr. of CaS04 are produced.

6.  EPA Source Classification Code
    3-01-012-O2  ROTRYKILN W/OSCRUB

7.  References
    1)  Bradbury, J. C. , Finger, G. C.,  and Major, R. L.,
        Fluorspar in Illinois,  Illinois  State  Geological
        Survey Circular  420, 1968, Urbana,  Illinois.

    2)  Encyclopedia of  Technology, Kirk-Othmer  2nd  Edition,
        Vol. 9,  Interscience Publishers, New York,  1966
        pp 610-625.
                               89

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HF PRODUCTION                                     PROCESS NUMBER 29

                  Hydrogen Fluoride Purification

1.  Function
    In  this process crude HF is purified by a series of sorption,
    desorption and distillation steps which utilize sulfuric
    acid  (H0SO J .  The volatile impurities are separated by these
            Jt   4
    steps  and  the impure HF is recovered from the H2S04 as >99%
    pure HF.  The towers and distillation apparatus needed to
    accomplish this can be made of steel.

2.  Input  Materials
    The feed materials to this process are composed primarily  of
    hydrogen fluoride, with small quantities of S02, SiF4, CO2,
    H2S04,  and H20.  The feed entering this process from the kiln
    (process 28) is composed of about 95% HF, 4% air and 1% of the
    above  impurities.  Further downstream weak sulfuric acid is  fed
    countercurrent to the main flow and acts as an absorbent for
    the hydrogen fluoride.

3.  Operating Parameters
    The product  from the kiln is fed into this process  at  about
    15O°C  where  it is cooled with condensers to liquefy the HF.
    The cooled gases are passed into the H2SO4 scrubber and  the
    HF  and H2O are absorbed into this solvent.  The H0SO con-
            •                                         24
    taining the  HF is subjected to warming for removal  by  dis-
    tillation of the >99% pure KF; the water remains  behind
    with the H2S04.

4.  Utilities
    Since  the product gases entering this process  are  at  temper-
    atures of  about  150°C,  they need only be cooled  to condense
                                90

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    the hydrogen fluoride (b.p. 19°C).  Cooling water must remove
    about 375,000 kcal. of heat per metric ton of hydrogen fluo-
    ride  produced.

5.  Waste Streams
    Gaseous HF and SiF4 are scrubbed out of the vent gases with
    water to form H2SiF4, which is marketed as a 3O-35% solution.

    A gaseous effluent of S02 and C02  is vented to the air.   The
    amounts of these gases which are vented will vary with the
    purity of the fluorspar used in process 28, but probably
    amount to less than 1O kg per metric ton of HF produced.

6.  EPA Source Classification
    3-01-012-01  ROTRYKILN W/SCRUB

7.  References
    1)  Finger, G. C., Risser, H. E., and Bradbury, J,  C.,
        "Illinois Fluorspar,"  Illinois State Geological
        Survey Circular 296, 1960.
    2)  Kirk-Othmer, Encyclopedia of Chemical Technology,
        2nd Edition, Vol. 9, Interscience Publishers, New York,
        1966, pp 61O-625.
                               91

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 APPENDIX A




RAW MATERIALS
     93

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 Table A-l.   LIST OF RAW MATERIALS


 acetic anhydride
 acetyl fluoride
 acetylene
 antimony pentachloride
 antimony trichloride
 aromatic chlorocarbons,  unspecified
 bromine
 carbon dioxide
 carbon tetrabromide
 carbon tetrachloride
 chlorine
 chloroform
 dimethyl ether
 ferrosilicon
 fluorspar,  2= 97% CaF2
 flotation agents, unspecified
 hexanes
 hexachloroacetone
 hexachlorobutadiene
 hydrocarbons,  unspecified
 hydrogen
 hydrogen fluoride
 iodine
 methylene chloride
 methyl sulfonyl fluoride
 phosphorus pentoxide
 potassium bifluoride
 potassium fluoride
 potassium permanganate
 pyridine compounds, unspecified
 pyrimidine compounds, unspecified
 sodium fluoride
 sodium hydroxide
 sodium silicate
 sulfuric acid
 tetrachloroethylene
 trichloroethylene
 tri-n-butylamine
-                94

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       APPENDIX B




PRODUCTS AND BY-PRODUCTS
           95

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Table B-l.  LIST OF PRODUCTS AND  BY-PRODUCTS
 bromotrifluoromethane
 calcium sulfate
 carbon dioxide
 l-chloro-l,l-difluoroethane
 chlorodifluoromethane
 chloropentafluoroethane
 chlorotrifluoroethylene
 chlorotrifluoromethane
 decafluorobutane
 dibromodifluoromethane
 1,2-dibromohexafluoropropane
 1,2-dibromotetrafluoroethane
 1,2-dichloro-1,1-difluoroethane
 1,2-dichloro-1,2-difluoroe thane
 l,l-dichloro-2,2-difluoroethylene
 1,2-dichloro-1,2-difluoroethylene
 dichlorodifluoromethane
 1,2-dichlorofluoroethane
 dichlorofluoromethane
 1,2-dichlorohexafluoropropane
 1,2-dichlorotetrafluoroethane
 1,1-difluoroethane
 1,1-difluoroethylene
 difluoromethane
 difluoromethyl trifluoromethyl ether
 fluoroethylene
 fluorinated aromatic compounds,  unspecified
 fluorinated heterocyclic compounds,  unspecified
 fluosilicic acid
 hexafluoroacetone
 hexafluoroacetone, sesquihydrate
 hexafluoroacetylacetone
 hexafluorobutyne-2
 hexafluorocyclobutene
 hexafluoroe thane
                       96

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 Table B-l (Continued).  LIST OF PRODUCTS  AND BY-PRODUCTS

         hexafluoroisopropanol
         hexafluoropropylene
         hydrogen bromide
         hydrogen chloride,  anhydrous
         hydrochloric acid
         1-iodoperfluorohexane
         manganese dioxide
         octafluorobutene-2
         octafluorocyclobutane
         octafluoropropane
         pentafluoroethane
         phosphoric acid
         silicon tetrafluoride
         silver iodide
         sodium fluoride
         sulfur dioxide
         1,1,1,2-tetrachloro-2,2-difluoroethane
         1,1,2,2-tetrachloro-l,2-difluoroethane
         1,1,1,3-te trachlorotetraf luoropropane
         1,1,2,2-tetrafluoroethane
         tetrafluoroethylene
         tetrafluorome thane
         trichlorofluoromethane
         2,2,3-trichloroheptafluorobutane
         1,1,2-trichloro-1,2,2-trifluoroethane
         1,1,1-trichloro-2,2,2-trifluoroethane
         1,1,1-trichloropentafluoropropane
         trifluoroacetic acid
         trifluoroacetic anhydride
         1,1,1-trifluoroethane
         1,2,2-trifluoroethane
         trifluoroethanol
         trifluoroethylene
         trifluoroethyl vinyl ether
         trifluoromethane
         bis(trifluoromethy1)  ether
	trifluoromethyl iodide	
                           97

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      APPENDIX C




PRODUCERS AND PRODUCTS
          99

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     Table C-l.  COMPANY/PRODUCT LIST


 Bromotrifluoromethane  (CBrF3)
    Du  Pont
 l-Chloro-l,l-difluoroethane  (CC1F2-CH3)
    Allied
    Du  Pont
    Pennwalt
 Chlorodifluoromethane  (CHC1F2)  (FC-22)
    Allied
    Du  Pont
    Pennwalt
    Union  Carbide
    Kaiser
    Racon
 Chioropentafluorbethane  (CC1F2-CF3)  (FC-115)
    Allied
    Du  Pont
 Chlorotrifluoroethylene  (CC1F=CF2)
    Allied
    Hooker
    3 M
 Chlorotrifluoromethane  (CC1F3)  (FC-13)
    Allied
    Du  Pont
    Pennwalt
 Decafluorobutane (C4F10)
    Phillips!

Dibromodifluoromethane  (CBr_F2)
     Du Pont
     PCR2

1,2-Dibromohexafluoropropane  (CBrF2-CBrF-CF3)
     Du Pont3
                    100

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Table C-l  (Continued).   COMPANY/PRODUCT LIST
 1,2-Dibromotetrafluoroethane (CBrF2-CBrF2)
      Du Pont
 1,2-Dichloro-l,1-difluoroethane (CC1F2-CH2C1)
      Phillips l

 1,2-Dichloro-l,2-difluoroethane (CHC1F-CHC1F)
      Phillips1
      PCR

 l,l-Dichloro-2,2-difluoroethylene (CC12=CF2)
      Allied
      PCR

 1,2-Dichloro-l,2-difluoroethylene (CC1F=CC1F)
      Allied
      PCR

 Dichlorodifluoromethane (CC12F2) (FC-12)
      Allied
      Du Pont
      Kaiser
      Pennwalt
      Racon
      Union Carbide

 1,2-Dichlorofluoroethane (CHC1F-CH2C1)
      Phillips1

 Dichlorofluoromethane  (CHC12F)  (FC-21)
      Allied
      Du Pont

 1,2-Dichlorohexafluoropropane  (CC1F2-CC1F-CF3)
      Du Pont3
                      1Q1

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      Table C-l (Continued).  COMPANY/PRODUCT LIST


1,2-Dichlorotetrafluoroethane (CC1F2-CC1F2) (FC-114)
     Allied
     Du Pont
     Union Carbide4
     Pennwalt1*

1,1-Difluoroethane (CHF2-CH3)
     Allied
     Du Pont

1,1-Difluoroethylene (CF2=CH2) (Vinylidene fluoride)
     Allied
     Du Pont

Difluoromethyl trifluoromethyl ether (CHF2-0-CF3)
     Phillips1

Fluoroethylene (CHF=CH2)  (Vinyl fluoride)
     Du Pont

Fluorinated Aromatic Chemicals (unspecified)
     Olin

Fluorinated Heterocyclic  Chemicals  (unspecified)
     Olin

Hexafluoroacetone  (CF3-CO-CF3)
     Allied5
     Du Pont
     Matheson5
     PCR5
     Phillips1
                            102.

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      Table  C-l  (Continued).   COMPANY/PRODUCT LIST
Hexafluoroacetone,  sesquihydrate (CF3-CO-CF3 •  1% H20)
     Du Pont
Hexafluoroacetylacetone  (CF3-CO-CH2-CO-CF3)
     PCR
Hexafluorobutyne-2 (CF3-C=C-CF3)
     PCR

Hexaf luorocyclobutene  ( [pjj)
     PCR
Hexafluoroethane  (CF3-CF3)  (FC-116)
     Du Pont
Hexafluoroisopropanol  (CF3-CHOH-CF3)
     Du Pont

Hexafluoropropylene  (CF3-CF-CF2)
     Du Pont
     PCR5

1- lodoperfluorohexane  (CF2I-CF 2-CF2-CF2-CF2-CF 3)
     Du Pont
     Thiokol

Octafluorobutene-2  (CF 3-CF=CF-CF 3)
     Halocarbon  5

Octafluoroeyclobutane  ( {?])  (FC-C318)
     Du Pont3
     Phillips1
                          103

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      Table C-l (Continued).   COMPANY/PRODUCT LIST


Octafluoropropane (CF3-CF2-CF3)
     Phillips1

Pentafluoroethane (CHF2-CF3)
     PCR
     Phillips1

1,1,1,2-Tetrachloro-2,2-difluoroethane (CC13-CC1F2)
     Allied5
     Du Pont5

l,l,2,2-Tetrachloro-l,2-difluoroethane (CC12F-CC12F)  (FC-112)
     Allied5
     Du Pont5
     Union Carbide1*

1,1,1,3-Tetrachlorotetrafluoropropane (CC13-CF2-CC1F2)
     Du Pont3

1,1,2,1-Tetrafluoroethane (CHF2-CHF2)
     Phillips1

Tetrafluoroethylene (CF2=CF2)
     Du Pont
     Pennwalt5
     Thiokol5

Tetrafluoromethane (CFO (FC-14)
     Du Pont

Trichlorofluoromethane  (CC13F) (FC-11)
     Allied
     Du Pont
     Pennwalt
     Union Carbide

                           1Q4

-------
       Table C-l (Continued).   COMPANY/PRODUCT LIST
2,2,3-Trichloroheptafluorobutane (CF3-CC12-CC1F-CF3)
     Halocarbon Products5

1,1,2-Trichloro-l,2,2-trifluoroethane (CC12F-CC1F2)  (FC-113)
     Allied
     Du Pont
     Kaiser
     Pennwalt
     Racon
     Union Carbide

1,1,l-Trichloro-2,2,2-trifluoroethane (CC13CF3)
     Allied6
     Du Pont6
     PCR"

1,1,1-Trichloropentafluoropropane (CC13-CF2-CF3)
     Du Pont3

Trifluoroacetic Acid  (CF3COOH)
     Halocarbon Products
     Phillips1

Trifluoroacetic Anhydride (CF3CO-0-CO-CF3)
     Halocarbon Products

1,1,1-Trifluoroethane  (CF3-CH3)
     Phillips1

1,2,2-Trifluoroethane  (CH2F-CHF2)
     Phillips1
                           1Q5

-------
         Table C-l (Continued).  COMPANY/PRODUCT LIST
   Trifluoroethanol (CF3CH2OH)
        Halocarbon Products

   Trifluoroethylene (CHF=CF2)
        PCR

   Trifluoroethyl vinyl ether (CF3-CH2-0-CH=CH2)
        Airco, Inc.

   Trifluoromethane (CHF3) (FC-23)
        Allied
        Du Pont

   bis(Trifluoromethyl) ether (CF3-0-CF3)
        Phillips1

   Trifluoromethyl iodide (CF3I)
        PCR

1)  Pilot plant only - now discontinued.
2)  Possible distributor only.
3)  Not currently in production - telecon.
4)  Probable producer not listed in 1976 DCP.
5)  Possibly not in current production.
6)  Not made as a pure product.
                              106

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          Table C-2.  PRODUCERS OF  FLUOROCARBONS
           Company              Annual Capacity (millions of kg)
E. I. du Pont de Nemours & Co.
Organic Chemicals Department
Freon Products Division
  Antioch, California
  Deepwater, New Jersey
  East Chicago, Indiana  >            230
  Louisville, Kentucky
  Montague, Michigan
Allied Chemical Corporation
Specialty Chemicals Division
  Baton Rouge, Louisiana
  Danville,  Illinois
  Elizabeth, New Jersey
  El Segundo, California -
Union Carbide Corporation
Chemicals and Plastics Dlv.
  Institute & South Charleston,
    West Virginia                      70
Pennwalt Corporation
Chemical Division
  Calvert City, Kentucky •!             53
  Thorofare, New Jersey  J
Kaiser Aluminum & Chemical Corp.
Kaiser Chemicals Division
  Gramercy, Louisiana                  23
Racon Incorporated
  Wichita, Kansas                       9
                              107

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            Table  C-3.   SPECIALITY FLUOROCHEMICALS LIST
    Airco,  Inc.
       Ohio  Medicap  Products  Division
       Cleveland,  Ohio

    Halocarbon Products Corporation
       82 Burlews  Court
       Hackensack, New Jersey  07601
    Hooker  Chemical Corporation
       Specialty Chemicals Division
       Niagara Falls, New York  14302
    Matheson Gas  Products
       Post  Office Box E.
       Lyndhurst,  New Jersey  07071
    3 M Company
       Commercial  Chemicals Division
       3 M Center
       Saint Paul, Minnesota,  55101
    01in Corporation
       12O Long Ridge Road
       Stamford, Connecticut  06904
   * Phillips Petroleum Company
       Chemical Dept./Commercial Development Division
       Bartlesville, Oklahoma  74004
    PCR, Inc.
       Gainesville,  Florida
    Thiokol Chemical Corporation
       P. 0. Box 1296
       Trenton, New  Jersey  08607

^Produced on a pilot plant basis  only - subsequently dis-
 continued
                               108

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            Table C-4.  PRODUCERS OF HYDROGEN FLUORIDE
       Company
Allied Chemical Corporation
Industrial Chemicals Division
    Baton Rouge, Louisiana
    Geismar, Louisiana
    Nitro, West Virginia
    North Claymont, Delaware
    Pittsburg, California
Annual Capacity (metric tons)
            98,000
E. I. du Pont de Nemours & Co., Inc.
Biochemicals Department
    LaPorte, Texas
            91,000
Aluminum Company of America
    Point Comfort, Texas
            50,000
Kaiser Aluminum & Chemical Corporation
Kaiser Chemicals Division
    Grammercy, Louisiana
            45,000
Pennwalt Corporation
Chemical Division
    Calvert City, Kentucky
            23,OOO
Stauffer Chemical Company
Industrial Chemical Division
    Greens Bayou, Texas
            16,OOO
Kewanee Oil Company
Harshaw Chemical Company, Division
Industrial Chemicals Department
    Cleveland, Ohio
            16,OOO
                               109

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Table C-4 (Continued).   PRODUCERS OF HYDROGEN FLUORIDE


 Olin Corporation
 Industrial  Products  and  Services Division
     Joliet,  Illinois                            12,OOO

 Essex Chemical  Corporation
 Chemicals Division
     Pausboro, New Jersey                        10,000

 Lehigh Valley Chemical Company
     Glendon, Pennsylvania                        4,000

          Total                                  361,000
 Source:  Chemical Marketing Reporter  7/15/73  p.  1.
                           110

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                                  TECHNICAL REPORT DATA
                           (Please read luatniciions on the reverse before completing)
  RfcPORT NO.
  EPA-600/2-77-023P
                             2.
1. TITLE AND SUBTITLE
 Industrial Process Profiles for Environmental  Use:
 Chapter l6.  The Fluorocarbon - Hydrogen  Floride
                Industry	
             3. RECIPIENT'S ACCESSION-NO.
             5. REPORT DATE
                February 1977
             6. PERFORMING ORGANIZATION CODE
•». AUTHOR(S)
 H. E. Doorenbus  (Dow Chemical)
 Terry Parsons, Editor
             8. PERFORMING ORGANIZATION REPORT NO.
9. PERFORMING ORGANIZATION NAME AND ADDRESS
 Radian Corporation
 8500 Shoal Creek Boulevard
 P.O. Bo:-:  99^8
 Austin. Texas  78766
             10. PROGRAM ELEMENT NO.

             1AB015
             11. CONTRACT/GRANT NO.
              68-02-1319, Task'
 12, SPONSORING AGENCY NAME AND ADDRESS
 Industrial Environmental Research Laboratory
 Office of Research and Development
 U.S. ENVIRONMENTAL PROTECTION AGENCY
 Cincinnati, Ohio   1*5268
             13. TYPE OF REPORT AND PERIOD COVERED
             _Ini1I al:  8/75-11/76	
             TiT'SPONSORING AGENCY CODE

               EPA/600/12
 16. SUPPLEMENTARY NOTES
 16. ABSTRACT
 The catalog of  Industrial Process Profiles for Environmental Use  was  developed as an
 aid in defining the environmental impacts  of industrial activity  in the United States,
 Entries  for each industry are in consistent format and form separate  chapters of the
 study.   The materials of the fluorocarbon-hydrogen fluoride industry  consist pri-
 marily of chemically and thermally  stable  organofluoro compounds  which generally
 have nontoxic and nonflammable qualities.   The industry is discussed  in two segments:
 (l)  Fluorocarbon Production and (2) Hydrogen Fluoride Production.  One chemical
 tree, fourteen  process flow sheets  and  twenty-nine process descriptions have been
 prepared to characterize the industry.   Within each process description available
 data have been  presented on input materials, operating parameters,  utility require-
 ments and waste streams.  Data related  to  the subject matter,  including company,
 product  and raw material dataware included as appendices.
17.
                                KEY WORDS AND DOCUMENT ANALYSIS
                  DESCRIPTORS
 Pollution
 Fluorocarbon
 Hydrogen Fluoride
 Organofluro Compounds
 Fluorocarbon  Production
 Hydrogen Fluoride Production
 Process Description
1«. DISTRIBUTION GT ATtMLN C
                     Release to Public
                                              b.lDENTIFIERS/OPEN ENDED TERMS
Air Pollution Control
Water Pollution Control
Solid Waste  Control
Stationary Sources
Fluoride  Compound Industry
19. SECURITY CLASS (IliisHepon)
	Unclassified	
aoTsfccurirf Y "CLASS (Tins pan'-')
   Unclassified
                             COSATI I-'ield.'Group
    07B
    07C
    13B
21. NO..OF PAGES
        119
                                                                         '21. PRICE
EPA Form 2220-1 (9-73)
                                            11.1

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