USES, SOURCES, AND
ATMOSPHERIC EMISSIONS
OFALKYLBENZENE
DERIVATIVES
Final Report
September 1979
By: Susan J. Mara
Edward C. So
Benjamin E. Suta
Prepared for:
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
SRI International
333 Ravenswood Avenue
Menlo Park, California 94025
(415)326-6200
Cable: SRI INTL MPK
WSS)
yinternational/
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USES, SOURCES, AND
ATMOSPHERIC EMISSIONS
OF ALKYLBENZENE
DERIVATIVES
Final Report
September 1979
By: Susan J. Mara
Edward C. So
Benjamin E. Suta
Prepared for:
U.S. Environmental Protection Agency
Office of Air Quality Planning and Standards
Research Triangle Park, North Carolina 27711
Task Officer: Richard J. Johnson
Project Officer: Joseph D. Cirvello
Contract No. 68-02-2835
SRI International Project No. CRU-6780
Center for Resource and Environmental
Systems Studies Report No. 101
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NOTICE
This report has been provided to the U.S. Environmental Protection
Agency (EPA) by SRI International, Menlo Park, California, in
fulfillment of Contract 68-02-2835. The opinions, findings, and
conclusions expressed herein are those of the authors and are not
necessarily those of EPA. Mention of company or product names is not to
be considered an endorsement by EPA.
n
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CONTENTS
LIST OF TABLES
ACKNOWLEDGMENTS
I SUMMARY
II ALLYLBENZENE
Ill CYCLOHEXYLBENZENE
IV DIISOPROPYLBENZENE
V DIVINYLBENZENE
VI DODECYLBENZENE
VII ETHYLBENZENE
VIII ETHYNYLBENZENE
IX HEXAMETHYLBENZENE
X ISOPROPYLBENZENE (CUMENE) . . .
XI PENTYLBENZENE
XII PROPENYLBENZENE
XIII PROPYLBENZENE
XIV STYRENE
XV TETRAMETHYLBENZENE .
XVI TOLUENE
XVII TRIETHYLBENZENE
XVIII TRIMETHYLBENZENE
XIX
XYLENE
BIBLIOGRAPHY
IV
v
1
4
5
6
7
9
15
21
22
23
27
28
29
30
37
38
50
51
53
65
111
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TABLES
1-1 Summary of Emissions of Alkylbenzene Derivatives 2
V-l Location of U.S. Producers of Divinylbenzene 8
VI-1 U.S. Producers and Estimated Production of Dodecylbenzene ... 13
VI-2 LAB Emission Rates and Sources for the Model Plant 14
VI-3 Estimated LAB Emissions by Location ..... 14
VII-1 U.S. Producers and Estimated Production of Ethylbenzene .... 17
VII-2 Emission Rates and Sources of Ethylbenzene for Styrene
Production Model Plant 19
VII-3 Estimated Emissions of Ethylbenzene by Location 20
X-l Location of U.S. Producers and Estimated
Production of Cumeme 25
XIV-1 Location of U.S. Producers and Estimated
Production of Styrene 33
XIV-2 Emission Rates and Sources of Styrene
for Styrene Production Model Plant 35
XIV-3 Estimated Emissions of Styrene by Location 36
XVT-1 Location of U.S. Producers and Estimated
Production of Toluene 43
XVI-2 Estimated Emissions of Toluene 47
XVIII-1 Location of U.S. Producers and Estimated Production of
Trimethylbenzene 52
XIX-1 Location of U.S. Producers and Estimated
Production of Xylene 58
XIX-2 Estimated Emissions of Xylenes 62
IV
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ACKNOWLEDGMENTS
It is a pleasure to acknowledge the cooperation and guidance given
by several individuals of the U.S. Environmental Protection Agency,
Office of Air Quality Planning and Standards. Richard Johnson,
Strategies and Air Standards Division, was task officer and provided
direction throughout the study. David Patrick, David Mascone, and K. C.
Hustvedt of the Emission Standards and Engineering Division supplied
valuable information on control technology and emission factors. Joseph
D. Cirvello was the project officer.
Ms. Emily Bulian, SRI International, Chemical Industries Center,
conducted the literature search for most of the chemicals reviewed. Mr.
Jeff Key of Hydroscience provided guidance on estimating ethylbenzene
and vinylbenzene emissions. The report was edited by Barbara Stevens.
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I SUMMARY
This report is one in a series that SRI International is providing
for the U.S. Environmental Protection Agency (EPA) on a quick-response
basis to estimate emissions of selected pollutants. The primary
objective of this study was to estimate the uses, sources, and
atmospheric emissions of 18 alkylbenzene derivatives. In some cases,
the major isomers of these derivatives were also evaluated. Only
emissions resulting from production of the chemicals were evaluated.
Most of these chemicals are also contained in petroleum and petroleum
products. Therefore, emissions from the petroleum and the
transportation industries, including automobiles, are expected to be
significant. However, these sources of emissions were not considered in
this report.
A number of sources were reviewed to obtain information on
production and uses of alkylbenzene derivatives. These include:
Directory of Chemical Producers (SRI, 1978); The Merck Index (Windholz,
1976); Kirk-Othmer Encyclopedia of Chemical Technology (Interscience
Publishers, several years); Chemical Economics Handbook (SRI), Chemical
Technology; An Encyclopedic Treatment (Barnes & Noble Books, 1972);
Chemical Origins and Markets (SRI, 1977); Hancock (1975); U.S.
International Trade Commission (1978, 1979); and "Chemical Profiles" in
Chemical Marketing Reporter (Schnell Publishing Company, 1978).
Although little data were available for many alkylbenzene
derivatives, most of these chemicals are known to be produced in very
low volume. Consequently, the estimated volume of emissions from their
production is also expected to be low. As shown in Table 1-1, SRI had
sufficient information to estimate emissions for 5 of the 18
alkylbenzene derivatives, accounting for approximately 91% of the total
production of these chemicals. All estimates were based on 1977 or 1978
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Table 1-1
SUMMARY OF EMISSIONS OF ALKYLBENZENE DERIVATIVES
Alkylbenzene
Derivative
Allylbenzene
Cyclohexylbenzene
Diisopropylbenzene
Divinylbenzene
Dodecylbenzene
Branched
Linear
Ethylbenzene
Ethynylbenzene
Hexamethylbenzene
Isopropylbenzene
(cumene)
Pentylbenzene
Propenylbenzene
Propylbenzene
Styrene
Tetramethylbenzene
Toluene
Triethylbenzene
Trimethylbenzene
Xylene
Mixed
Ortho
Meta
Para
Total
Estimated
Production
(IP-3 mt)
P
U
0.002+
0.005+
98
238
3,700
0.0005+
U
1,450
0.0005+
U
0.001+
3,100
0.0005+
4,200
U
0.002+
2,882
460
40
1,590
Number of
Sources
U
U
1
4
2
4
13
1
U
16
1
U
3
14
1
41
U
3
31
2
1
9
Estimated Annual
Emissions (mt)
N
N
S
S
S
20
500
N
N
SA
N
N
N
320
N
150
N
N
90
10
1
50
18,301+
147+c
1,141+
Individual estimates rounded to two significant figures; a
letter indicates that available information did not allow
calculation of emissions, but that a qualitative assessment was
possible as follows: N, expected to be negligible; S, may be
significant; SA, expected to be less than 200 mt annually.
^U = Unknown
cSome companies make several alkylbenzene derivatives.
Therefore, this total is too high if combined sources are taken
into consideration.
Source: SRI; most production data obtained from U.S. International
Trade Commission (1978 and 1979).
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data on production. SRI estimated total production of alkylbenzene
derivatives to be greater than 18 x 10 metric tons (mt) annually.
The results of our analysis indicate that ethylbenzene has the
highest emissions per unit of production, followed by styrene
(vinylbenzene). Emission estimates were developed based on rough
estimates of fugitive, storage, and handling emissions. Differing
levels of emission control were assumed based on consultation with EPA
to arrive at an overall emission factor for each chemical.
These estimates are subject to considerable uncertainty regarding
volume of production, locations of sources, emissions from each
facility, and control technologies employed. Our review of available
information indicated that production of alkylbenzene derivatives varies
widely from year to year and that number and location of companies
producing these chemicals changes annually. Therefore, these estimates
are only useful to obtain an approximation of the relative volumes,
number of sources, and estimated emissions of each chemical. Much more
detailed analysis of emission characteristics of each chemical is
required to improve these estimates.
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II ALLYLBENZENE
A. Uses
No reference was found to indicate specific uses.
B. Production
SRI was unable to obtain any information concerning allylbenzene
(2-propenylbenzene; 3-phenyl-l-propene; l-phenyl-2-propene) in any one
of a number of sources reviewed. Thus, we assume this chemical to be
commercially insignificant.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. However, the lack of information on the production of
this chemical indicates that the volume of production is probably low.
Consequently, atmospheric emissions from any facility producing
allylbenzene are most likely negligible on an annual basis.
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Ill CYCLOHEXYLBENZENE
A. Uses
Cyclohexylbenzene appears to be produced in low volume for use as a
high-boiling solvent, penetrating agent, intermediate, or laboratory
reagent.
B. Production
SRI was unable to obtain any information concerning the absolute
volume of production or the location of manufacturers for
cyclohexylbenzene (phenylcyclohexane). Therefore, we assume this
chemical to be commercially insignificant.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. However, the lack of information on the production of
this chemical indicates that the volume of production is probably low.
Consequently, atmospheric emissions from any facility producing
cyclohexylbenzene are most likely negligible on an annual basis.
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IV DIISOPROPYLBENZENE
A. Uses
Diisopropylbenzene is produced in low volume for use as an
intermediate or occasionally as a solvent. One of its isomers,
p-diisopropylbenzene, is used as an intermediate to terephthalic acid,
which is used for the manufacture of Terylene (Dacron) fibers
(Interscience Publishers, 1965; Barnes & Noble Books, Inc., 1972).
B. Production
Diisopropylbenzene is manufactured by the alkylation of cumene with
propylene. Production of diisopropylbenzene (isomer unspecified) in
1977 was probably greater than 2.3 mt. Dow Chemical U.S.A (location
unknown) was the only listed producer. This production most likely took
place in their Midland, Michigan plant. Because of the low volume of
production, diisopropylbenzene and its isomers are assumed to be
commercially insignificant.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. Because the estimated level of production is somewhat
high, atmospheric emissions may be significant in the vicinity of the
manufacturer.
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V DIVINYLBENZENE
A. Uses
The primary use for divinylbenzene is in styrene-divinylbenzene
resins formed by cross-linking polystyrene beads with divinylbenzene to
produce the most common matrix base for ion-exchange resins. Typically,
a styrene-divinylbenzene ion-exchange resin contains about 92% styrene
and 8% divinylbenzene, although resins with 1-16% divinylbenzene are
commercially available. Other ion-exchange resin matrices commonly used
are methyl acrylate-divinylbenzene copolymer and terpolymer resins. The
major uses of ion-exchange resins are water treatment (softening and
deionization) and chemical processing (e.g., sugar purification,
pharmaceutical manufacture, uranium processing). Other materials
competing with ion-exchange resins include powdered and granular
activated carbon and membrane materials.
B. Production
Divinylbenzene is a specialty monomer used to produce cross-linked
polystyrene resins. The monomer is manufactured by dehydrogenation of
mixed isomeric diethylbenzenes. Commercial divinylbenzene monomer
generally consists of diluted mixtures of m- and p-divinylbenzene
(Coulter et al., 1967).
Divinylbenzene is produced at four locations (see Table V-l).
Production in 1977 was greater than 4.5 mt (U.S. International Trade
Commission, 1978). Because commercial divinylbenzene is essentially a
mixture of m- and p-divinylbenzene, the manufacturers listed in Table
V-l are assumed to be producers of these two isomers. No commercial
production of o-divinylbenzene was indicated in any of a number of
sources reviewed, and therefore, SRI assumed it to be commercially
insignificant.
7
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Table V-l
LOCATION OF U.S. PRODUCERS OF DIVINYLBENZENEa
1977
Company Location Estimated Production (mt)
American Hoechst Corp.
Baton Rouge, LA U^
Atlantic Richfield Company
Beaver Valley, PA U
Dow Chemical USA
Midland, MI U
Foster Grant Company, Inc.
Baton Rouge, LA U
Total 4.5+
aCommercial divinylbenzene is composed of m- and p-divinylbenzene.
°U = unknown
Source: U.S. International Trade Commission, 1978; SRI.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. The estimated level of production is high enough to
indicate that atmospheric emissions may be significant at some
locations, depending on the distribution of production among the four
manufacturers. Baton Rouge, with two divinylbenzene manufacturers, is
probably the location with the highest total emissions.
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VI DODECYLBENZENE
A. Uses
Dodecylbenzene is the commercial name given to any alkylbenzene
containing a straight chain alkyl group with 11 to 14 carbons and
averaging 12 carbons. Dodecylbenzene, or detergent alkylate, is formed
from the alkylation of benzene with dodecene. The product is either
branched or linear alkylbenzene (dodecylbenzene), depending on the
olefin reactant in the process. Prior to 1966, branched alkylbenzene
was used as a raw material for the large domestic household detergent
market. The surfactant, alkylbenzene sulfonates (ABS), produced from
branched alkylbenzene, was only slowly biodegradable because of
branching on the alkyl group, and this condition caused foam to be
formed in rivers and streams. Consequently, a "soft" surfactant, linear
alkylbenzene sulfonates (LAS), produced from linear alkylbenzene (LAB)
that did degrade at an acceptable rate, was developed.
Since 1966, domestic production of branched alkylbenzene has been
responsive mainly to export market demands. U.S. exports of branched
alkylbenzene in 1977 accounted for about 84% of the total production (82
3
x 10 mt). The remaining 16% was used in the United States primarily
as emulsifiers in pesticides and agricultural chemical formulations, and
as industrial surfactants (e.g., for oils and lubricants).
Although commercial production of linear alkylbenzene was initiated
in 1964, U.S. producers did not convert their production of domestic
household synthetic detergents to the exclusive use of LAB-derived LAS
until 1966. Approximately 90% of the annual production of linear
alkylbenzene is consumed domestically, with the remaining 10% exported.
SRI estimated the 1977 consumption pattern for linear alkylbenzene
based on the requirements of the LAS markets in the United States:
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for home heavy-duty laundry detergents in powder form, 52%; in liquid
form, 12%; for home light-duty liquid dishwashing detergents, 16%; for
industrial, institutional, and commercial applications, 17%; and for
household cleansers and miscellaneous uses, 4%.
The future of linear alkylbenzene is completely dependent on future
production of the principal household detergent surfactant, LAS. A
modest increase of 1-2% per year is projected because newer detergents
are coming on the market.
B. Production
Branched-chain alkylbenzene is produced by alkylating benzene in
much the same manner as is done in the internal olefin process. The raw
material, however, is propylene tetramer (branched dodecene), which is
obtained during the manufacture of polymer gasoline from refinery
polymerization units; either hydrogen fluoride or aluminum chloride is
the catalyst.
As shown in Table VI-1, branched alkylbenzenes are produced at two
locations in California. The 1978 capacities of these two facilities
3 3
totalled 111 x 10 mt. Production in 1977 was 98 x 10 mt, or 88%
of the 1978 capacity (U.S. International Trade Commission, 1979).
In the United States, essentially all LAB is produced from benzene
and normal paraffin mixtures that are in the C,0 to C,, chain length
range and have an average chain length of about 12. Normal paraffins,
however, cannot be used directly to produce LAB. They are first
converted to the corresponding monochloroparaffin or linear internal
olefin and then reacted with benzene to produce the LAB. The two
processes currently used in the United States are discussed below.
1. Monochloroparaffin Process
Three of the four U.S. producers of LAB use the monochloroparaffin
process. The basic steps are as follows:
10
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CH3(CH2)XCH3 + CI2
CH3(CH2)yCH2CH(CH2)zCH3 + HCI
normal chlorine
paraffins
(averaging C12)
Cl
monochloroparaffms hy
(averaging Ci2) chloride
CH3(CH2)yCH2CH(CH2)zCH3 +
Cl
monoch I propa raf f i ns
(averaging C12)
Aid-
*- CH3(CH2)yCH2CH(CH2)zCH3 + HCI
benzene
LAB
(averaging Ci2alkv|)
hydrogen
chloride
2. Linear Internal Olefin Process
Monsanto Company is the only company in the United States producing
LAB by dehydrogenating normal paraffins. The reaction steps are as
follows:
CH3(CH2)XCH3 •
normal paraffins
(averaging
Pt-alumina
catalyst
CH3(CH2)yCH CH(CH2)ZCH3 + H2
internal olefins
(averaging C12)
CH3(CH2)yCH = CH(CH2)ZCH3
internaj olefins
(averaging C-|2)
HF
benzene
CH3(CH2)yCH2CH(CH2)2CH3
linear alkylbenzene
(averaging C^2 a Iky I)
11
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Linear alkylbenzene is produced at four locations in four states
(Maryland, Texas, West Virginia, and California). Virtually all LAB
produced in the United States is used as a raw material for the
production of LAS. Table VI-1 lists the producers, locations,
capacities, production, and uses for linear alkylbenzene.
C. Emissions
Linear alkylbenzene is a viscous liquid with low vapor pressure
(0.4 Pascal) at ambient conditions. The predominant emission from its
production is benzene, which is emitted as a gas.
Detailed emission data for branched alkylbenzene and LAB are not
available. Available information did not allow calculation of emissions
or emission rates of branched alkylbenzene. However, based on a recent
study by Hydroscience (1978), emission rates were estimated for LAB
o
based on two 90 x 10 mt/yr model plants - the LAB olefin process
model plant and the LAB chlorination process model plant. Model plants
were assumed to operate 8,000 hours annually, and have physical
characteristics typical of existing operating plants. Table VI-2
summarizes the emission rates and sources of LAB for the model plants.
Thus, the emission rates of LAB for the LAB olefin process are
0.899 kg/hr (80 kg/103 mt of LAB produced) and 0.079 kg/hr (7 kg/103
mt of LAB produced) for the uncontrolled and controlled conditions.
Similarly, the emission rates of LAB for the LAB chlorination process
are 2.717 kg/hr (240 kg/103 mt of LAB produced) and 0.175 kg/hr (20
2
kg/10 mt of LAB produced) for the uncontrolled and controlled
conditions. Assuming 50% of the processes are controlled, the average
o
emission rates are 0.489/kg/hr (40 kg/10 mt of LAB produced) for the
LAB olefin process and 1.446 kg/hr (130 kg/103 mt of LAB produced) for
the LAB chlorination process. Based on these emission rates, the annual
atmospheric emission of LAB is calculated to be about 20 mt. The
atmospheric emissions of LAB by U.S. producers are listed in Table VI-3.
12
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Table VI-1
U.S. PRODUCERS AND ESTIMATED PRODUCTION OF DODECYLBENZENE
Company Location
Branched Alkylbenzenei
Standard Oil Co.
of California
Richmond, CA
1978
Capacity
(103 mt)
100
1978
Estimated
Production
(103 mt)
Unknown
Use
Mostly export
Witco Chemical Corp.
Carson, CA
11
Unknown
Mostly export
Total
111
Unknown*
Linear Alkylbenzene;
Continental Oil Co.
Baltimore, MD 109
Monsanto Company
Chocolate Bayou, TX 102
Union Carbide Corp.
Institute, WV 64
Witco Chemical Corp.
Carson, CA 20
88
82
52
16
LAS markets
LAS markets
LAS markets
LAS markets
Total
295
238
*The 1977 production of branched alkylbenzene is estimated to be 98 x
metric tons.
Source: SRI; production data derived based on data from U.S. International
Trade Commission (1979).
13
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Table VI-2
LAB EMISSION RATES AND SOURCES FOR THE MODEL PLANT
LAB Emission Rates (kg/hr)
Source LAB Olefin Process LAB Chlorination Process
Process Negligible Negligible
Storage and Handling
Uncontrolled 0.098 0.233
Controlled 0.0 0.0
Fugitive*
Uncontrolled 0.801 2.484
Controlled 0.079 0.175
*Assuming 50% of volatile organic compounds (excluding benzene) are
Source: Hydroscience (1978)
Table VI-3
ESTIMATED LAB EMISSIONS BY LOCATION
LAB 1978
Manufacturing Estimated
Company Location Process Emissions (mt)
Continental Oil Co. Chlorination
Baltimore, MD process 11
Monsanto Company
Chocolate Bayou, TX Olefin process 4
Union Carbide Corp. Chlorination
Institute, WV process 7
Witco Chemical Corp. Chlorination
Carson, CA process 2
Total 24
Source: SRI.
14
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VII ETHYLBENZENE
A. Uses
The annual U.S. ethylbenzene capacity as of January 1, 1979 is
4,300 x 103 mt with the 1978 production at 87% of this capacity (3,700
o
x 10 mt; U.S. International Trade Commission, 1979). Most
ethylbenzene (96%) is consumed captively for styrene monomer
production. In addition, 2% is used as a solvent and 2% is exported
(Schnell Publishing Co., 1978). On occasion, ethylbenzene is also used
in the production of diethylbenzene, acetophenone, and ethyl
anthraquinone.
Because almost all ethylbenzene produced is consumed in the
manufacture of styrene, domestic ethylbenzene demand will grow at about
the same rate as styrene production, roughly 3% annually from 1978 to
1983, amounting to 4,100 x 103 mt in 1983.
B. Production
Ethylbenzene is produced primarily by the alkylation of benzene
with ethylene. This process is carried out either in the liquid phase
using aluminum chloride as the catalyst, or in the vapor phase with a
phosphoric acid or alumina-silica catalyst. In either case, yields
above 95% are obtained. The reaction is as follows:
CgHg T C(i2 ~~ Cri2 *
benzene ethylene ethyl benzene
15
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Approximately 0.28 metric ton of ethylene and 0.76 metric ton of benzene
are consumed per metric ton of ethylbenzene produced by alkylation.
Ethylbenzene is produced at 19 locations in 3 states (Texas,
Louisiana, and Michigan) and Puerto Rico. Table VII-1 lists the U.S.
manufacturers, estimated production, and types of uses for
ethylbenzene. Production is estimated as 87% of capacity.
C. Emissions
Ethylbenzene is liquid at ambient conditions. The predominant
emission from ethylbenzene producton is ethane; other emissions are
benzene, ethylbenzene, and ethylene.
Detailed emission data for ethylbenzene are not available.
However, in a recent EPA study (Mascone, personal communication, July
1979), the emission rates of ethylbenzene were computed based on a model
styrene production plant. The model plant has a capacity of
3 x 10 mt and operates 8,000 hours <
typical of many operating facilities,
3 x 10 mt and operates 8,000 hours annually. This model plant is
Emission rates and sources of ethylbenzene for the styrene
production model plant are summarized in Table VII-2.
Thus, the emission rates of ethylbenzene for the styrene production
o
model plant are 9.7 kg/hr (260 kg/10 mt of styrene produced) and 0.69
o
kg/hr (18 kg/10 mt of styrene produced) for uncontrolled and
controlled conditions, respectively.
Assuming 70% of the emissions are controlled in the process stream,
50% of the emissions are controlled in the storage facilities, and 25%
of the fugitive emissions are controlled (Mascone, 1979), the average
emission rate of ethylbenzene is calculated to be 5.851 kg/hr (160
o
kg/10 mt of styrene produced).
16
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Table VII-1
U.S. PRODUCERS AND ESTIMATED PRODUCTION OF ETHYLBENZENE
Company Location
American Hoechst
Corporation
Baton Rouge,
LA
Bayport, TX
American Petrofina,
Incorporated
Big Spring, TX
Atlantic Richfield
Company
Houston, TX
Port Arthur, TX
The Charter Co.
Houston, TX
Commonwealth Oil
Refining Co., Inc.
Penuelas, PR
COS-MAR, Inc.
Carville, LA
Dow Chemical USA
Midland, MI
El Paso Natural
Gas Co.
Odessa, TX
Gulf Oil Corp.
Donaldsonville,
LA
1978 Capacity
(103 mt)
1978 Estimated
Production (10 mt)
Use
526
460
Captive
(A 469 x 1Q3 metric ton-per-yr ethylbenzene plant
is scheduled for completion in 1980.)
(A 20 x 1Q3 metric ton-per-yr unit is on standby.)
62
114
54
100
Captive
Captive
16 14 Sold
(A 72 x 1Q3 metric ton-per-yr unit is on standby.)
690
794
125
313
604
695
109
274
Captive
Captive
Captive
Captive
17
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Table VII-1 (Concluded)
Company Location
Monsanto Company
Alvin (Chocolate
Bayou), TX
Texas City, TX
Oxirane Corporation
Channelview, TX
Standard Oil Co. of
Indiana
Texas City, TX
Sun Company, Inc.
Corpus Christi,
TX
Tenneco, Inc.
Chalmette, LA
1978 Capacity
(103 mt)
27
744
525
286
61
1978 Estimated
3
Production (10 mt)
24
650
459
250
53
Use
Captive
Captive
Captive
Captive
Captive
(A 16 x 103 metric ton-per-yr plant is on standby.)
Union Carbide Corp.
Seadrift, TX (A 154 x 103 metric ton-per-yr plant is on standby.)
Total
4,283
3,746
aDerived based on data from U.S. International Trade Commission, 1979,
Source: SRI.
18
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Table VII-2
EMISSION RATES AND SOURCES OF ETHYLBENZENE
FOR STYRENE PRODUCTION MODEL PLANT
Emission Rates (kg/hr)
Source From Ethylbenzene Unit From Styrene Unit
Process
Uncontrolled 2.5 0.5
Controlled 0.025 0.005
Storage*
Uncontrolled 1.1
Controlled 0.06
Fugitive
Uncontrolled 2.8 2.8
Controlled 0.3 0.3
*For the entire plant.
Source: Mascone (1979).
Because virtually all ethylbenzene produced is consumed captively
for styrene production and an average of 1.165 mt of ethylbenzene is
required to produce 1 mt of styrene, the emission rate of ethylbenzene
2
can also be expressed as 134 kg/10 mt of ethylbenzene produced.
Based on this emission rate, and the 1978 estimated ethylbenzene
production, the annual atmospheric emission of ethylbenzene is about 500
mt. The estimated atmospheric emissions of ethylbenzene by the U.S.
ethylbenzene producers are listed in Table VII-3.
19
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Table VII-3
ESTIMATED EMISSIONS OF ETHYLBENZENE BY LOCATION
1978 Estimated
Company Location Emissions (mt)
American Hoechst Corp.
Baton Rouge, LA 61
Atlantic Richfield Co.
Houston, TX 7
Port Arthur, TX 13
The Charter Co.
Houston, TX 1*
COS-MAR, Inc.
Carville, LA 81
Dow Chemical USA
Midland, MI 93
El Paso Natural Gas Co.
Odessa, TX 15
Gulf Oil Corp.
Donaldsonville, LA 37
Monsanto Company
Alvin (Chocolate Bayou), TX 3
Texas City, TX 87
Oxirane Corporation
Channelview, TX 62
Standard Oil Co. of Indiana
Texas City, TX 34
Sun Company, Inc.
Corpus Christi, TX 7
Total 501
*Emission rate of 80 kg/103 mt of ethylbenzene produced is used.
Source: SRI.
20
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VIII ETHYNYLBENZENE
A. Uses
No reference was found to indicate specific uses of this chemical.
B. Production
Ethynylbenzene (phenylacetylene; phenylethyne) is produced in a
very small quantity, but probably exceeding 450 kg in total. Only one
firm produces this chemical—Aldrich Chemical Company, Inc., Milwaukee,
Wisconsin. Because of the low volume of production, ethynylbenzene is
assumed to be commercially insignificant.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. However, the apparent low volume of production
indicates that atmospheric emissions from any facility producing
ethynylbenzene are most likely negligible on an annual basis.
21
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IX HEXAMETHYLBENZENE
A. Uses
No reference was found to indicate specific uses of this chemical.
B. Production
SRI was unable to obtain any information concerning the volume of
production or the location of manufacturers for hexamethylbenzene
(mellitene). Therefore, we assume that this chemical is commercially
insignificant.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. However, the lack of information on the production of
this chemical indicates that the volume of production is probably low.
Consequently, atmospheric emissions from any facility manufacturing
hexamethylbenzene are most likely negligible on an annual basis.
22
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X ISOPROPYLBENZENE (CUMENE)
A. Uses
Approximately 1.5 x 10 mt of isopropylbenzene (cumene) were
produced in the United States in 1978 (U.S. International Trade
Commission, 1979). Nearly all was used in the manufacture of phenol and
acetone. The following statistics present the consumption pattern for
cumene: 65% for the production of phenol, which is then used to make
phenolic resins, bisphenol A, and caprolactam; 34% for the production of
acetone, which is then used to make methyl methacrylate, methyl isobutyl
ketone, bisphenol A, and other related compounds; and 1% for the
production of alpha-methylstyrene, acetophenone, and other miscellaneous
applications.
Since 1968, cumene production has increased at a rate of 7.8% per
year. Future growth is expected to slow somewhat to 4.5% per year
through 1982. The outlook for both phenol and cumene demand is
essentially the same, because about 96% of domestic phenol is derived
from cumene and nearly all cumene is consumed in phenol and acetone
manufacture.
B. Production
Although cumene is present in many crude oils and refinery streams,
all commercial cumene is manufactured by the alkylation of benzene with
propylene. Benzene and propylene (in a propylene/propane stream) are
reacted under elevated temperature and pressure in the presence of a
catalyst. Typically, the catalyst is solid phosphoric acid on an
alumina support, although sulfuric acid or aluminum chloride might also
be used. The reaction is represented as follows:
23
-------
4- CH2.= CH -CH3
benzene propylene
Cumene is produced at 16 locations in 7 states and Puerto Rico (see
Table X-l). In the 1950s, nearly all cumene produced was consumed
captively. Currently, however, about half of the domestic production is
sold commercially. In 1978, production was estimated at 65.7% of
capacity of the plants operating during the year.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. However, individual production levels are large with
seven facilities producing more than 100,000 mt per year. These data
indicate that atmospheric emissions may be significant in the vicinity
of these facilities throughout the year (assuming frequent production of
cumene at the facilities). Texas has nine such facilities, with three
of them located in Corpus Christi. Consequently, the Houston and Corpus
Christi petrochemical refining areas can be expected to be the locations
with the highest total emissions, and therefore the highest ambient
concentrations, of cumene. An order-of-magnitude estimate of emissions
can be made by comparing cumeme to ethylbenzene, which has the highest
emission per unit of production. SRI estimates that total cumene
emissions are most likely less than 200 mt annually.
24
-------
Table X-l
LOCATION OF U.S. PRODUCERS AND ESTIMATED PRODUCTION OF CUMENE
Company Location
1979
Capacity
(103 mt)
1978
Estimated3
Production
(103 mt)
Useb
Ashland Oil, Inc.
Catlettsburg, KY 181
Clark Oil & Refining
Corp.
Blue Island, IL 50
Coastal States Gas
Corp.
Corpus Christi, TX 64
Georgia-Pacific Corp.
Houston, TX
Getty Oil Co.
El Dorado, KS
Gulf Oil Corp.
Philadelphia, PA
Port Arthur, TX
Marathon Oil Co.
Texas City, TX 95
Monsanto Company
Chocolate Bayou, 340
TX
Shell Chemical Co.
Deer Park, TX 326
Standard Oil Co.
of California
El Segundo, CA 45
Standard Oil Co.
of Indiana
Texas City, TX 14
Sun Company, Inc.
Corpus Christi, TX 113
120
30
-c
-d
220
210
30
10
70
Sold
Captive
340
61
209
204
220
i
40
140
130
50% Captive
Captive
Sold
Sold
Captive
Captive
Captive
Captive
Sold
25
-------
Table X-l (Concluded)
Company Location
Texaco, Inc.
Westville, NY
Union Carbide Corp.
Penuelas, PR
Union Pacific Corp.
Corpus Christi, TX
Total
1979
Capacity
(103 mt)
64
290
1978
Estimated3
Production
(103 mt)
40
190
-e
Use
Sold
Partially
captive
2,396
1,450
Production is estimated as 65.7% of capacity, based on production
data from U.S. International Trade Commission (1979).
identifies whether cumene is sold or used captively to produce
another product.
cNo production in 1978 because facility was being converted to
produce both cumene and polygas chemicals.
currently in operation.
eA 181 x 10-* mt plant is scheduled for completion in early 1980.
Source: SRI.
26
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XI PENTYLBENZENE
A. Uses
No reference was found to indicate specific uses.
B. Production
SRI was unable to obtain any information concerning sec- or
tert-pentylbenzene in any one of a number of sources reviewed. Thus, we
assume these chemicals to be commercially insignificant.
In 1977, more than 450 kg of n-pentylbenzene (amylbenzene;
1-phenylpentane) was produced by one manufacturer—the Humphrey Chemical
Company, North Haven, Connecticut.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. However, the apparent low volume of production
indicates that atmospheric emissions from any facility manufacturing
pentylbenzene are most likely negligible on an annual basis.
27
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XII PROPENYLBENZENE
A. Uses
No reference was found to indicate specific uses.
B. Production
SRI was unable to obtain any information concerning propenylbenzene
(1-phenyl-l-propene; beta-methylstyrene) in any one of a number of
sources reviewed. Thus, we assume this chemical to be commercially
insignificant.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. However, the lack of information on the production of
this chemical indicates that volume of production is probably low.
Consequently, atmospheric emissions from any facility producing
propenylbenzene are most likely negligible on an annual basis.
28
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XIII PROPYLBENZENE
A. Uses
No reference was found to indicate specific uses of this chemical.
B. Production
Propylbenzene (isocumene; 1-phenylpropane; n-propylbenzene) is
produced in a very small quantity, but probably exceeding 1,400 kg in
total. Three firms produce this chemical—Eastman Kodak Company,
Rochester, New York; Ethyl Corporation, Orangeburg, South Carolina; and
the Humphrey Chemical Company, North Haven, Connecticut. Because of the
low volume of production, propylbenzene is assumed to be commercially
insignificant.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. However, the apparent low volume of producton indicates
that atmospheric emissions from any facility producing propylbenzene are
most likely negligible on an annual basis.
29
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XIV STYRENE
A. Uses
In 1978, styrene (vinylbenzene) production in the United States
o
totalled 3,100 x 10 mt (U.S. International Trade Commission, 1979).
Virtually all styrene is consumed in polymer manufacture, with more than
half used to manufacture polystyrenes.
Packaging applications account for more than one-third of the
polystyrene consumed; other diversified end uses are toys, sporting
goods, appliances and cabinets, housewares, electrical parts, and
disposable serviceware and flatware. The 1977 consumption pattern for
polystyrenes was estimated as follows: high-impact or rubber-modified
polystyrene, 28%*; straight polystyrene, 22%; styrene-butadiene rubber
(SBR), 8.7%; acrylonitrile-butadiene-styrene resins (ABS resins), 7.9%;
styrene-butadiene resins, 5.3%; unsaturated polyester resins, 5.7%;
styrene-acrylonitrile resins, 1.2%; export, 15%; and other uses, 6.2%.
Based on average annual growth rates of polystyrene and styrene
copolymers, the principal derivatives of styrene, styrene demand is
expected to increase at an average annual rate of 4.5-5.0% from 1978 to
1983. Styrene exports in recent years have averaged about 12-15% of
domestic production. As more styrene plants outside of the United
States come on stream, the U.S. export market will become less
important, and SRI estimates that styrene exports will decrease to 5-6%
of domestic production in 1983.
*Contains 3-10% polybutadiene rubber.
30
-------
B. Production
Styrene is produced from ethylbenzene dehydrogenation or as a
coproduct of propylene oxide.
1. Ethylbenzene Dehydrogenation
As of January 1977, all U.S. plants catalytically dehydrogenate
high-purity (99%) ethylbenzene in the vapor phase to produce styrene.
Consumption is 1.13 to 1.20 kilograms of ethylbenzene per kilogram of
styrene produced.
C6H5CH2CH3
ethylbenzene
C6H5CH = CH2 + H2
styrene
2. Propylene Oxide Coproduct
The production of styrene as a coproduct of propylene oxide
manufacture has been commercialized in Spain. In the process shown,
C6H5CH2CH3 + 02
ethylbenzene
C6H5CHOOHCH3
ethybenzene
hydroperoxide
C6H5CHOOHCH3 + CH3CH = CH2
ethylbenzene
hydroperoxide
propylene
C6HgCHOHCH3 + CH3CHCH2
methylphenyl O
carbinol
propylene
oxide
C6H5CHOHCH3
methylphenyl
carbinol
C6H5CH CH2 + H2O
styrene
31
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ethylbenzene is oxidized to its hydroperoxide, which is then reacted
with propylene to yield propylene oxide and its coproduct, methyl phenyl
carbinol. The carbinol is then dehydrated to styrene. Styrene is
produced at 14 locations in 4 states (Texas, Louisiana, Pennsylvania,
and Michigan). Table XIV-1 lists the U.S. manufacturers, their
locations, and estimated production of styrene. Production is estimated
at 77% of capacity. Virtually all styrene produced is consumed in
polymer manufacture.
C. Emissions
Benzene is the predominant emission from styrene production; other
emissions are toluene, ethylbenzene, styrene, and ethane.
Detailed emission data for styrene are not available. However, in
a recent EPA study (Mascone, personal communication, July 1979), the
emission rates of styrene were computed based on a model styrene
production plant. The model plant has a capacity of 3 x 10 mt and
operates 8,000 hours annually, which is typical of many operating
facilities.
Emission rates and sources of styrene for the styrene production
model plant are summarized in Table XIV-2. The emission rates of
o
styrene for the styrene production model plant are 6 kg/hr (160 kg/10
o
mt of styrene produced) and 0.605 kg/hr (16 kg/10 mt of styrene
produced) for uncontrolled and controlled conditions, respectively.
Assuming 70% of the emissions are controlled in the process stream,
50% of the emissions are controlled in the storage facilities, and 25%
of the fugitive emissions are controlled (Mascone, 1979), the average
o
emission rate of styrene is calculated to be 3.83 kg/hr (100 kg/10 mt
of styrene produced). Based on this emission rate and the 1978
estimated styrene production, the annual atmospheric emission of styrene
is about 320 mt. The estimated atmospheric emissions of styrene for
U.S. producers are listed in Table XIV-3.
32
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Table XIV-1
LOCATION OF U.S. PRODUCERS AND ESTIMATED PRODUCTION OF STYRENE
Company Location
American Hoechst Corp.
Baton Rouge, LA
American Petrofina, Inc.
Big Spring, TX
Atlantic Richfield Co.
Houston, TX
Kobuta, PA
Beaver Valley, PA
Beaver Valley, PA
COS-MAR, Inc.
Carville, LA
Dow Chemical, USA
Freeport, TX
Midland, MI
El Paso Natural Gas
Odessa, TX
Gulf Oil Corp.
St. James, LA
Monsanto Company
Texas City, TX
Oxirane Corporation
Channelview, TX
Standard Oil Co. of
Indiana
Texas City, TX
1978
Capacity
(103 mt)
1978
Estimated
Production
(103 mt)
Use
449
345
Partly captive
(A 40 x 10^ metric ton-yr plant is on standby.)
50
195
100
(A 45 x
590
680
147
115
272
680
454
245
39
150
77
Captive
Captive
Captive
metric ton-yr plant is on standby.)
454
523
113
89
209
523
349
188
Partly captive
Partly captive
Mostly captive
Sold
Sold
Partly captive
Sold
Partly captive
33
-------
Table XIV-1 (Concluded)
1978
Capacity
,3
1978
Estimated
Production
(103 mt)
Company Location (10"' mt) (10'' mt) Use
Standard Oil of Indiana
Texas City, TX (A 116 x 103 metric tons-yr plant is on standby.)
Sun Company
Corpus Christi, TX
36
28
Sold
Union Carbide Corp. (A 136 x 103 metric tons-yr plant in on standby.)
Seadrift, TX
U.S. Steel Corp.
Houston, TX
Total
54
42
Partly captive
4,067
3,129
Source: SRI; production data derived based on data from U.S. International
Trade Commission (1979).
34
-------
Table XIV-2
EMISSION RATES AND SOURCES OF STYRENE
FOR STYRENE PRODUCTION MODEL PLANT
Source
Process
Uncontrolled
Controlled
Storage
Uncontrolled
Controlled
Fugitive
Uncontrolled
Controlled
Emission Rate (kg/hr)
0.5
0.005
2.7
Unknown (assumed 0.3)
2.8
0.3
Source: Ma scone (1979).
35
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Table XIV-3
ESTIMATED EMISSIONS OF STYRENE BY LOCATION
Company Location
American Hoechst Corp.
Baton Rouge, LA
Atlantic Richfield Co.
Houston, TX
Kobuta, PA
Beaver Valley, PA
COS-MAR, Inc.
Carville, LA
Dow Chemical USA
Freeport, TX
Midland, MI
El Paso Natural Gas
Odessa, TX
Gulf Oil Corp.
St. James, LA
Monsanto Company
Texas City, TX
Oxirane Corporation
Channelview, TX
Standard Oil Co. of Indiana
Texas City, TX
Sun Company
Corpus Christi, TX
U.S. Steel Corp.
Houston, TX
1978
Estimated
Emissions (mt)
35
4
15
8
46
53
12
9
21
53
36
19
Total
318
Source: SRI.
36
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XV TETRAMETHYLBENZENE
A. Uses
One isomer of tetramethylbenzene, 1,2,4,5-tetramethylbenzene
(durene), is used as a raw material for pyromellitic dianhydride (PMDA),
which is used to make high-temperature-resistant polymers. These
polymers are used in molded parts, film, fibers, and insulating
varnishes. PMDA is also used as a cross-linking agent for epoxy and
other resins (Interscience Publishers, Inc., 1968).
B. Production
Durene is converted to PMDA by three processes. In the first,
durene is oxidized by chromic acid and then thermally dehydrated to
PMDA. Because of the relatively high volatility of anhydride groups,
PMDA can also be made by vapor-phase oxidation of durene. Thirdly, a
vanadium pentoxide catalyst is used to oxidize durene without requiring
a subsequent distillation for purification.
Production of durene in 1977 probably exceeded 450 kg. Only one
company is producing durene—Sun Company, Inc., Corpus Christi, Texas.
C. Emissions
Available information did not allow calculation of emissions or
emission rates. The estimated level of production is low, which
indicates that atmospheric emissions from the facility are probably
negligible on an annual basis.
37
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XVI TOLUENE
A. Uses
3
The production of toluene in 1978 totalled 4,180 x 10 mt (U.S.
International Trade Commission, 1979). Essentially all toluene comes
from petroleum sources; about 1-2% of the amount isolated in 1978 was
derived from coal. Of the quantity isolated from petroleum, about 89%
was obtained from catalytic reformate, 9% from pyrolysis gasoline, and
the remaining 2% as a by-product of styrene manufacture. In addition,
about 25 x 10 mt of toluene produced in petroleum operations
(primarily in catalytic reformate) were not isolated from refinery
streams, but were consumed directly in the gasoline pool.
The largest single (but fluctuating) use of isolated toluene is in
the production of benzene through hydrodealkylation (HDA). Use of HDA
has been an effective means of balancing supply and demand of benzene.
When benzene is in good supply, the dealkylation units are shut down.
Of the three major aromatic chemicals (benzene, toluene, and
xylene), toluene is the most important in solvent applications, with the
major use being in surface coatings. Significant amounts also are used
in adhesives, inks, Pharmaceuticals, other formulated products requiring
a solvent carrier, numerous industrial applications, and in commercial
solvent products.
Aromatic solvent markets have been adversely affected since the
establishment of Rule 66 in Los Angeles in 1967. With similar
restrictive ordinances established in other parts of the country, and
with federal exposure limits administered by the Occupational Safety and
Health Administration (OSHA), solvent users have reformulated many
products to reduce the use of aromatics. In October 1975, OSHA proposed
38
-------
a standard for exposure to toluene. Demand for toluene as a solvent has
declined significantly since 1975 and is expected to decline further by
1980.
Toluene diisocyanate (TDI), the most important isocyanate raw
material for the production of polyurethane materials, is produced by
phosgenating the toluene diamines, which are manufactured by reducing
dinitrotoluenes.
Benzyl chloride is produced by chlorinating the side chain of
toluene. Benzyl chloride production is estimated to have been 32 x
3 3
10 mt in 1975, requiring nearly 25 x 10 mt of toluene. About
two-thirds of the benzyl chloride produced is used in the manufacture of
the diester butyl benzyl phthalate. Butyl benzyl phthalate is used
widely as a plasticizer in the manufacture of polyvinyl chloride
flooring compositions for which it provides stain resistance. The
second largest end use for benzyl chloride is in the synthesis of benzyl
alcohol, which is used as a dye assist, in photography, and in making
Pharmaceuticals and perfumes. In addition, benzyl chloride serves as a
raw material for disinfectants, bactericides, perfumes, and
Pharmaceuticals.
Benzoic acid is obtained by oxidation of toluene with air in the
presence of a catalyst. Benzoic acid is used as a chemical
intermediate. Its largest single use is in the manufacture of phenol.
In addition, benzoic acid is used in three product areas—benzoate
plasticizers, sodium benzoate, and benzoyl chloride.
Toluene is also used as a raw material for the manufacture of
phenol. While phenol has numerous and diverse outlets, the
toluene-derived phenol is produced in the Pacific Northwest and is
therefore used chiefly for one end use—the manufacture of phenolic
(phenolformaldehyde) adhesive resins for the local softwood, plywood,
and, to a lesser extent, the particle board industry.
39
-------
There are a number of less significant uses of toluene, including
the production of vinyl toluene, cresols, toluene sulfonic acids,
toluene sulfonates, trinitrotoluene (and dinitrotoluene) for explosive
applications, nitrotoluenes, dinitrotoluenes, toluene diamine (IDA),
benzaldehyde (oil of bitter almond), benzotrichloride
(trichlorotoluene), xylenes, chlorotoluenes, toluenesulfonyl chlorides,
para-tert-butyl benzoic acid, dodecyltoluene, terephthalic acid,
caprolactam, styrene, and as a denaturant.
B. Production
Most toluene is now petroleum-derived. Small quantities are
produced as a by-product of styrene manufacture, and some coal-derived
toluene is still produced.
1. Petroleum-Derived Toluene
Toluene is present in crude oil (in low concentrations) and in the
gasoline fractions that result from thermal and catalytic cracking. The
chief source of toluene is catalytic reformate; the second most
important source is pyrolysis gasoline.
Catalytic reforming is used on a large scale in the United States
to convert the naphthenes and paraffins in a low octane naphtha to a
high octane component of gasoline. In some cases, reforming also is
used specifically to provide aromatics for chemical use.
As of January 1, 1976, catalytic reforming capacity in place in the
United States amounted to approximately 3.6 million barrels of feed per
stream day or about 53 billion gallons of feed per year. If 53 billion
gallons of straight-run naphtha were fed to reforming, about 45 billion
gallons of reformate containing 20-30 billion gallons of aromatics would
be produced. Of these aromatics, toluene would comprise 30-40%, or
about 9 billion gallons. Present capacity to separate toluene from
catalytic reformate is more than 1,200 million gallons (3,900 x 10
40
-------
mt) per year. However, much of the toluene contained in the catalytic
reformate is not potentially available for chemical use because it
remains in the catalytic reformate utilized in the gasoline pool. The
use of both isolated toluene and the unseparated toluene in catalytic
reformate for gasoline blending is highly desirable.
Pyrolysis gasoline ("dripolenes" or "cracked distillate") is the
by-product liquid stream that results when paraffins such as propane and
n-butane or heavier hydrocarbons such as condensates, naphtha, and gas
oil are cracked for the manufacture of olefins. The amount of pyrolysis
gasoline produced depends not only on the type of feed used for olefin
manufacture but also on the conditions of cracking. The by-product
pyrolysis gasoline contains a high percentage of aromatics. Of the
aromatics, benzene is present in the largest quantity and significant
quantities of benzene are reclaimed from pyrolysis gasoline. Usually,
the amount of pyrolysis gasoline coproduced with olefins as a result of
cracking the lower paraffins is too small to make the recovery of
toluene attractive, but the heavier olefin feeds (naphtha, gas oil, or
condensate) yield fairly large amounts of pyrolysis gasoline. The
quantity of toluene in the pyrolysis gasoline resulting from cracking
these feeds can range from 0.10 to 0.25 kilograms per kilogram of
ethylene, depending on the feed material and on the severity of the
cracking.
Before toluene can be isolated from pyrolysis gasoline, the latter
must be treated to remove any olefins and diolefins. Not all pyrolysis
gasoline produced in the United States is tapped for toluene recovery,
3
but some companies do isolate the toluene. About 230 x 10 mt of
toluene were reclaimed from pyrolysis gasoline in 1975.
2. By-Product of Styrene Production
When ethylbenzene is dehydrogenated to produce styrene, some
toluene is also synthesized; 1.6 to 2.6 kg of toluene is obtained with
each 45 kg of styrene produced. The by-product toluene is then
41
-------
reclaimed and used for gasoline blending or as feed to
hydrodealkylation. Because of impurities, it is not suitable for
o
chemical and solvent use. Approximately 82 to 115 x 10 mt of toluene
were obtained in 1975 as a by-product of styrene production.
3. Coal-Derived Toluene
The high-temperature carbonization of coal produces coke, which
yields by-product coal tar and by-product crude light oil, both of which
contain some toluene. Coal tar is seldom used as a source of toluene,
but some toluene is isolated from crude light oil. The quantity of
toluene that is isolated from crude light oil by tar distillers is
negligible, and the amount isolated by coke-oven operators is very
small. In 1975, the quantity of toluene produced by coke-oven operators
accounted for only 1% of total production. (This does not include
toluene produced from light oil processed by petroleum refiners).
Petroleum refiners, who purchase and process crude light oil, reclaimed
some of the toluene present in the light oil. Approximately
3
50 x 10 mt of toluene were isolate
purchased crude light oil in 1975.
3
50 x 10 mt of toluene were isolated by petroleum refiners from
Toluene is produced at 41 locations in 14 states, the Virgin
Islands, and Puerto Rico. Table XVI-1 lists the U.S. producers, their
locations, and estimated productions of toluene. The production of
toluene in 1978 was approximately 81% of the available capacity.
C. Emissions
Toluene is produced at petroleum refineries or petrochemical
complexes, which typically produce xylene and benzene as well. Benzene
emissions from these facilities have previously been estimated (Mara and
Lee, 1978). No detailed analysis has been done to quantify toluene
emissions. However, these emissions are expected to be similar to those
resulting from benzene production at the same facility (Hustvedt,
42
-------
Table
LOCATION OF U.S. PRODUCERS AND
XVI-1
ESTIMATED PRODUCTION OF TOLUENE
Company Location
Amerada Hess Corp.
St. Croix, VI
American Petrofina, Inc.
Beaumont, TX
Big Spring, TX
Ashland Oil, Inc.
Ashland, KY
N. Tonawanda, NY
Atlantic Richfield
Channelview, TX
Houston, TX
Wilmington, CA
Bethlehem Steel
Sparrows Point, MD
CF&I Steel Corp.
Pueblo, CO
The Charter Co.
Houston, TX
Coastal States Gas
Corpus Christi, TX
Commonwealth Oil
Refining Co., Inc.
Ponce, PR
Crown Central
Petroleum Corp.
Pasadena, TX
1978
Capacity
(103 mt)
460
<3
Negligible
50
60
390
50
50
1978
Estimated
Production
(103 mt)
370
120
160
100
30
40
10
140
120
50
100
130
80
30
30
10
110
100
40
<3
Negligible
40
50
320
40
40
Raw
Material
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Coke-oven light oil
Catalytic reformate
Coke-oven light oil
Pyrolysis gasoline
Catalytic reformate
Catalytic reformate
Coke-oven light oil
Coke-oven light oil
Catalytic reformate
Catalytic reformate
Catalytic reformate
Pyrolysis gasoline
Catalytic reformate
43
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Table XVI-1 (Continued)
Company Location
Dow Chemical, USA
Freeport, TX
Exxon Corp.
Baytown, TX
Getty Oil Company
El Dorado, KS
Gulf Oil Corp.
Alliance, LA
Philadelphia, PA
Port Arthur, TX
Kerr-McGee Corp.
Corpus Christi, TX
LTV Corporation
Aliquippa, PA
Marathon Oil Co.
Texas City, TX
Mobil Corporation
Beaumont, TX
Monsanto Co.
Chocolate Bayou, TX
Phillips Petroleum Co.
Sweeny, TX
Guayama, PR
Quintana-Howell Joint
Venture
Corpus Christi, TX
1978
Capacity
(103 mt)
13
410
13
210
90
50
70
150
70
280
16
30
130
30
340
60
1978
Estimated
Production
(103 mt)
10
332
10
170
80
40
50
120
60
220
13
30
110
30
270
50
Raw
Material
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Pyrolysis gasoline
Catalytic reformate
Coke-oven light oil
Catalytic reformate
Catalytic reformate
Pyrolysis gasoline
Catalytic reformate
Pyrolysis gasoline
Catalytic reformate
Catalytic reformate
Catalytic reformate
44
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Table XVI-1 (Concluded)
1978
Capacity
3
Company Location (10 mt)
Shell Chemical Co.
Deer Park, TX
Sun Company
Corpus Christi, TX
Marcus Hook, PA
Toledo, OH
Tulsa, OK
Tenneco, Inc.
Chalmette, LA
Texaco, Inc.
Port Arthur, TX
Westville, NJ
Union Carbide Corp.
Taft, LA
Union Oil Co. of
California
Lemont, IL
Union Pacific Corp.
Corpus Christi, TX
United States Steel
Clairton, PA
Geneva, UT
Total
200
70
60
100
30
3
1978
Estimated
Production
(103 mt)
160
140
150
250
70
100
90
130
110
120
200
50
80
80
110
50
50
80
20
3
Raw
Material
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Catalytic reformate
Pyrolysis gasoline
Catalytic reformate
Catalytic reformate
Coke-oven, light oil
Coke-oven light oil
5,192
4,205
Source: SRI; production data derived based on data from U.S. International
Trade Commission (1979).
45
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personal communication, July 1979). Therefore, for this analysis SRI
used similar emission factors.
The estimated emission factors for benzene production ranged from
o
30 to 50 kg/10 mt, depending on the amount of storage and handling
required as well as the types of emission controls at the facility (Mara
and Lee, 1978). Storage and handling tend to increase emissions.
Because more than 90% of the toluene production is used in gasoline, SRI
assumed that storage and handling emissions would be somewhat reduced
from benzene, but increased from xylene production. Therefore, a
o
somewhat conservative emission factor of 35 kg of emissions per 10 mt
of production was selected. The results of this analysis are presented
in Table XVI-2.
46
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Table XVI-2
ESTIMATED EMISSIONS OF TOLUENE
Company Location
Amerada Hess Corp.
St. Croix, VI
American Petrofina, Inc.
Beaumont, TX
Big Spring, TX
Ashland Oil, Inc.
Ashland, KY
N. Tonawanda, NY
Atlantic Richfield
Channelview, TX
Houston, TX
Wilmington, CA
Bethlehem Steel
Sparrows Point, MD
CF&I Steel Corp.
Pueblo, CO
The Charter Co.
Houston, TX
Coastal States Gas
Corpus Christi, TX
Commonwealth Oil
Refining Co., Inc.
Ponce, PR
Crown Central
Petroleum Corp.
Pasadena, TX
Dow Chemical, USA
Freeport, TX
1978
Estimated Emissions
(mt)
13
4
5
4
1
4
4
1
Negligible
Negligible
13
Negligible
47
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Table XVI-2 (Continued)
Company Location
Exxon Corp.
Baytown, TX
Getty Oil Company
El Dorado, KS
Gulf Oil Corp.
Alliance, LA
Philadelphia, PA
Port Arthur, TX
Kerr-McGee Corp.
Corpus Christi, TX
LTV Corporation
Aliquippa, PA
Marathon Oil Co.
Texas City, TX
Mobil Corporation
Beaumont, TX
Monsanto Co.
Chocolate Bayou, TX
Phillips Petroleum Co.
Sweeny, TX
Guayama, PR
Quintana-Howell Joint
Venture
Corpus Christi, TX
Shell Chemical Co.
Deer Park, TX
Sun Company
Corpus Christi, TX
Marcus Hook, PA
1978
Estimated Emissions
(mt)
12
Negligible
6
3
3
Negligible
1
9
4
4
48
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Table XVI-2 (Concluded)
Company Location
Sun Company (Continued)
Toledo, OH
Tulsa, OK
Tenneco, Inc.
Chalmette, LA
Texaco, Inc.
Port Arthur, TX
Westville, NJ
Union Carbide Corp.
Taft, LA
Union Oil Co. of
California
Lemont, IL
Union Pacific Corp.
Corpus Christi, TX
United States Steel
Clairton, PA
Geneva, UT
1978
Estimated Emissions
(mt)
7
2
3
4
Negligible
Total
149
Source: SRI.
49
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XVII TRIETHYLBENZENE
A. Uses
Two isomers of triethylbenzene were investigated: 1,2,4-triethylbenzene
and 1,3,5-triethylbenzene. No reference was found to indicate specific uses
of either of these chemicals.
B. Production
SRI was unable to obtain any information concerning 1,2,4- and
1,3,5-triethylbenzene in any one of a number of sources reviewed. Thus, we
assume this chemical to be commercially insignificant.
C. Emissions
Available information did not allow calculation of emissions or emission
rates. However, the lack of information on the production of these chemicals
indicates that the volume of production is probably low. Consequently,
atmospheric emissions from any facility producing these chemicals are most
likely negligible on an annual basis.
50
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XVIII TRIMETHYLBENZENE
A. Uses
SRI reviewed three isomers of trimethylbenzene: 1,2,3-trimethylbenzene
(hemimellitene); 1,2,4-trimethylbenzene (pseudocumeme; pseudocumol); and
1,3,5-trimethylbenzene (mesitylene). Specific uses were only indicated for
1,2,4-trimethylbenzene, which is used as a raw material for trimellitic
anhydride (TMA). TMA is used in the production of triisooctyl and triisodecyl
esters of trimellitic acid. These esters are used as vinyl plasticizers in a
variety of applications. In addition, 1,2,4-trimethylbenzene is used in the
production of poly(amide-imide) polymers for use in wire enamels and
electrical-insulating varnishes (Interscience Publishers, Inc., 1968).
B. Production
Trimethylbenzene is produced at three locations, as shown in Table
XVIII-1. Total production is estimated to probably exceed 1.8 mt. Because no
information was available to indicate specific uses and because volume of
production is low, 1,2,3-trimethylbenzene and 1,3,5-trimethylbenzene are
assumed to be commercially insignificant. In addition, the low volume of
1,2,4-trimethylbenzene produced indicates that this chemical is commercially
insignificant as well.
C. Emissions
Available information did not allow calculation of emissions or emission
rates. However, the low volume of production at each location indicates that
atmospheric emissions from facilities producing these chemicals can be
expected to be negligible on an annual basis.
51
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Table XVIII-1
LOCATION OF U.S. PRODUCERS AND
ESTIMATED PRODUCTION OF TRIMETHYLBENZENE
Company Location
Aldrich Chemical
Co., Inc.
Milwaukee, WI
Chemical
Produced
1,2,3-trimethylbenzene
1977 Estimated
Production (kg)
450+
Phillips Petroleum
Phillips, TX 1,2,4-trimethylbenzene
Sun Oil Co. of
Pennsylvania
Corpus Christi,
TX
1,2,4-trimethyIbenzene
1,3,5-trimethyIbenzene
a
450+
Total
l,800a
aTotal production of 1,2,4-trimethylbenzene is listed as
greater than 900 kg. No information is available concerning the
level of production at each facility.
Source: SRI.
52
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XIX XYLENE
A. Uses
Xylene (dimethylbenzene) is produced and sold as mixed xylenes or
as one of three isomers—ortho-xylene (o-xylene), meta-xylene
(m-xylene), and para-xylene (p-xylene). Production of mixed xylenes
totalled more than 2,800 x 10 mt in 1978 (U.S. International Trade
Commission, 1979.
Approximately 65% of the mixed xylenes produced is isomerized,
primarily into p-xylene (49%) and o-xylene (12.5%), with additional
smaller production into ethylbenzene (2.5%) and m-xylene (1%).
Approximately 26% is used in gasoline back-blending as a high octane
blending stock and in miscellaneous uses, such as intermediates in the
manufacture of xylene sulfonates and xylidenes. The remaining 9% of
mixed xylenes production is used in solvents, primarily paints and
coatings (6%). Additional solvent uses include agricultural sprays,
adhesives, and rubber.
Ortho-xylene is used in the manufacture of phthalic anhydride,
which is used chiefly in phthalic plasticizers. The major use for
phthalic plasticizers is in flexible polyvinyl chloride. Demand for
o-xylene is expected to closely follow the demand for phthalic
plasticizers, which is estimated to grow at a rate of 4.0-4.5% per year
through 1983. Production of o-xylene, however, is expected to increase
only 1.5-2.0% per year because of decreasing exports of the chemical.
Meta-xylene is used primarily in the manufacture of isophthalic
acid, which is used to make: (1) isophthalic polyester resins for use
in press molding, contact molding, and gel coats; (2) alkyd resins for
use as surface coating resins; and (3) miscellaneous applications such
53
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as plasticizers (di [2-ethylhexyl] isophthalate), polyester fibers and
films, and high-temperature-resistant aromatic polyamide fibers. In
addition, small quantities of m-xylene are used to produce m-toluic acid
and isophthalonitrile (IPN). M-toluic acid is the chemical intermediate
for a mosquito repellant (N,N-diethyl-m-toluamide). IPN is used in the
production of a fungicide(tetrachloroisophthalonitrile), guanamine
resins, and m-xylene diamine. Assuming declining imports of m-xylene,
production of this chemical is expected to grow at an average of 8.5%
annually through 1983.
Most p-xylene produced is consumed in the production of dimethyl
terephthalate and terephthalic acid, both of which are used in the
production of polyethylene terephthalate—the polymer for the
manufacture of polyester fibers and polyester films. Because net
exports of p-xylene are expected to drop, overall production is only
expected to grow at the rate of 5.5% per year through 1983.
B. Production
1. Mixed Xylenes
Mixed xylenes are either petroleum-derived or coal-derived. The
petroleum-derived xylenes are those reclaimed by petroleum refiners or
petrochemical producers from catalytic reformate and pyrolysis
gasoline. The coal-derived mixed xylenes are those isolated by
coke-oven operators and tar distillers from the light oil that results
from coking operations, and by petroleum refiners or petrochemical
producers from purchased light oil from coke ovens.
About 95% of total mixed xylenes was derived from catalytic
reformate in 1978. The feed to the reformer to produce aromatics for
chemical use is usually a naphthene-rich (35-40% by volume) straight-run
gasoline fraction boiling in the range of 66°C-132°C. The amount of
mixed xylenes contained in the catalytic reformate varies widely,
typically ranging from 18 to 33 volume percent of the reformate.
54
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About 5% of mixed xylenes production was from pyrolysis gasoline in
1978. Pyrolysis gasoline is a by-product that results when hydrocarbon
feeds are cracked for olefin manufacture. The mixed xylenes content of
pyrolysis gasoline varies greatly, depending on the feed and the
severity at which the cracking process is operated.
Less than 1% of mixed xylenes production is derived from coal.
When coal is subjected to high-temperature carbonization for the
manufacture of coke, it yields a crude light oil that contains 3-6%
mixed xylenes by volume. This light oil is then processed by the
coke-oven operators or tar distillers to obtain a light naphtha
containing mixed xylenes and styrene. The mixed xylenes present in
light oil are not always reclaimed, and the amount of mixed xylenes that
can be obtained from the light oil is very small.
2. Xylene isomers
Until mid-1969, the individual isomers of xylene were obtained in
the United States exclusively from the mixed xylenes produced by
petroleum refiners. Ethylbenzene, o-xylene, m-xylene, and p-xylene are
obtained by fractioning mixed xylenes and, in some cases, the m-isomer
is isomerized to form additional o- and p-xylene. Since 1969, the
disproportionation of toluene, an additional method of obtaining
xylenes, has been used commercially at times.
a. Isolation
O-xylene is separated from mixed xylenes by conventional
distillation. Distillation of mixed xylenes yields 95-98% pure o-xylene
(by weight).
The most commonly used means for isolating high-purity p-xylene
streams (99.0-99.5% by weight) is a two-stage, low-temperature
crystallization process. If the stream contains only the p- and m-
isomers, the first crystallization yields a slurry, which can then be
55
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recrystallized into high-purity p-xylene. Approximately 50-65% of the
p-xylene in the mixed xylene stream can be recovered, and the remainder
stays in the filtrate from crystallization.
In addition, p-xylene also can be isolated by adsorption. In one
process, a C_ fraction is passed over an adsorption bed and the
p-xylene is selectively retained on the adsorbent. Material other than
p-xylene retained on the adsorbent is removed by backwashing the
adsorbent with p-xylene. P-xylene is then separated from the adsorbent
by washing with a desorbent hydrocarbon, and is subsequently separated
from the desorbent hydrocarbon by distillation.
After crystallizaton of p-xylene, m-xylene is contained in the
remaining filtrate. This mixture, which contains 85% m-xylene, can be
oxidized to a mixture of isophthalic and terephthalic acids, a procedure
followed by Amoco Chemicals Corporation. Alternatively, the filtrate
can be used as a source of higher purity (e.g., 98%) m-xylene. Various
other methods are occasionally used for obtaining m-xylene.
b. Isomerization
After p-xylene has been obtained by crystallization, the remaining
filtrates can be used to augment p-xylene production by (1) isomerizing
the other xylene isomers and/or ethylbenzene to yield additional
p-xylene, and (2) recycling the p-xylene-enriched mixture to p-xylene
separation (crystallization). A variety of isomerization processes have
been used commercially.
56
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c. Toluene Disproportionation and Transalkylation with Higher
Methylbenzenes
Several companies have developed processes that disproportionate
(transalkylate) toluene to benzene and xylenes.
CH
toluene
benzene
CH
xylene
The ratio of xylenes to benzene may be increased by adjusting the
operating conditions and by adding trimethylbenzene to the toluene feed.
CH3 4-
CH3
trimethylbenzene
toluene
CH3
xylene
Depending on the amount of trimethylbenzene added, the xylene-benzene
product ratio can be maximized at 10:1.
The 1978 estimated production of mixed xylenes and xylene isomers
is shown in Table XIX-1. Although ethylbenzene is considered an isomer
of xylene, this chemical was the subject of a separate chapter (see
Chapter VII). We estimated production as a percentage of capacity as
follows: mixed xylenes, 49%; o-xylene, 85%; m-xylene, 53%; and
p-xylene,
57
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Table XIX-1
LOCATION OF U.S. PRODUCERS AND ESTIMATED PRODUCTION OF XYLENE
1978 Estimated Production (10 mt)
Company Location Mixed xylene o-xylene m-xylene p-xylene
Amerada Hess Corp.
St. Croix, VI 220
American Petrofina, Inc.
Big Spring, TX 100
American Petrofina of
Texas/Union Oil Co.
of California
Beaumont, TX 20
Ashland Oil, Inc.
Catlettsburg, KY 50
Tonawanda, NY 20
Atlantic Richfield Co.
Channelview, TX 40
Houston, TX 150 80 110
The Charter Company
Houston, TX 20
Cities Service Co.
Lake Charles, LA 80
Coastal States Gas
Corpus Christi, TX 80
Commonwealth Oil
Penuelas, PR 190
Crown Central Petroleum
Pasadena, TX 20
Exxon Co., USA
Baytown, TX 200 80 130
Gulf Oil Corp.
Alliance, LA 100
58
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Table XIX-1 (Continued)
Company Location
Hercor Chemical Corp.
Penuelas, PR
Kerr-McGee Corp.
Corpus Christi, TX
Marathon Oil Co.
Texas City, TX
Monsanto Co.
Chocolate Bayou, TX
Phillips Petroleum
Guayama, PR
Quintana Petroleum/
Howe 11 Hydrocarbons
Corpus Christi, TX
St. Croix Petrochemical
St. Croix, VI
Shell Chemical
Deer Park, TX
Standard Oil of
California
Pascagoula, MS
Richmond, CA
Standard Oil of
Indiana
Texas City, TX
Whiting, IN
Sun Company
Corpus Christi, TX
Marcus Hook, PA
Toledo, OH
1978 Estimated Production (10 mt)
Mixed xylene o-xylene m-xylene p-xylene
70
20
180
30
160
20
120
100
100
390
290
40
60
80
10
50
140
60
180
30
390
270
40
60
120
59
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Table XIX-1 (Concluded)
3
1978 Estimated Production (10 mt)
Company Location Mixed xylene o-xylene m-xylene p-xylene
Tenneco, Inc.
Chalmette, LA 60 50 40
Union Carbide
Taft, LA 30
Union Oil Co. of
California
Lemont, IL 20
Union Pacific Corp. 2
Clairton, PA
Total 2,882 460 40 1,590
Source: SRI estimates based on total production data from U.S. International
Trade Commission (1979).
C. Emissions
Xylenes are produced at petroleum refineries or petrochemcial complexes,
which typically produce toluene and benzene in addition to xylene or its
isomers. Benzene emissions from these facilities have previously been
estimated (Mara and Lee, 1978). No detailed analysis has been done to
quantify xylene emissions. However, these emissions are expected to be
similar to those resulting from benzene production at the same facility
(Hustvedt, personal communication, July 1979). Therefore, for this analysis
SRI used similar emission factors.
The estimated emission factors for benzene production ranged from 30
o
to 50 kg/10 mt depending on the amount of storage and handling required as
well as the types of emission controls at the facility (Mara and Lee, 1978).
Storage and handling tend to increase emissions. Because 65% of xylene
60
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production is used to manufacture xylene isomers, SRI assumed that storage and
handling would be somewhat reduced. Therefore, a somewhat conservative
3
emission factor of 30 kg of emissions per 10 mt of production was
selected. The results of this analysis are presented in Table XIX-2.
61
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Table XIX-2
ESTIMATED EMISSIONS OF XYLENE
1978 Estimated Emissions (mt)
Company Location Mixed xylene o-xylene m-xylene p-xylene
Amerada Hess Corp.
St. Croix, VI 7
American Petrofina, Inc.
Big Spring, TX 3
American Petrofina of
Texas/Union Oil Co.
of California
Beaumont, TX 1
Ashland Oil, Inc.
Catlettsburg, KY 2
Tonawanda, NY 1
Atlantic Richfield Co.
Channelview, TX 1
Houston, TX 52 3
The Charter Company
Houston, TX 1
Cities Service Co.
Lake Charles, LA 2
Coastal States Gas
Corpus Christi, TX 2
Commonwealth Oil
Penuelas, PR 6
Crown Central Petroleum
Pasadena, TX 1
Exxon Co., USA
Baytown, TX 62 4
Gulf Oil Corp.
Alliance, LA 3
62
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Table XIX-2 (Continued)
Company Location
Hercor Chemical Corp.
Penuelas, PR
Kerr-McGee Corp.
Corpus Christi, TX
Marathon Oil Co.
Texas City, TX
Monsanto Co.
Chocolate Bayou, TX
Phillips Petroleum
Guayama, PR
Quintana Petroleum/
Howe 11 Hydrocarbons
Corpus Christi, TX
St. Croix Petrochemical
St. Croix, VI
Shell Chemical
Deer Park, TX
Standard Oil of
California
Pascagoula, MS
Richmond, CA
Standard Oil of
Indiana
Texas City, TX
Whiting, IN
Sun Company
Corpus Christi, TX
Marcus Hook, PA
Toledo, OH
1978 Estimated Emissions (mt)
Mixed xylene o-xylene m-xylene p-xylene
3
3
12
9
1
2
2
12
8
63
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Source: SRI.
Table XIX-2 (Concluded)
Company Location
Tenneco, Inc.
Chalmette, LA
Union Carbide
Taft, LA
Union Oil Co. of
California
Lemont, IL
Union Pacific Corp.
Clairton, PA
1978 Estimated Emissions (mt)
Mixed xylene o-xylene m-xylene p-xylene
Total
91
13
47
64
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