Process for the production of a polymeric carbamate

A process for the production of polymeric carbamate from polyalkylene polyamines which provides for the efficient separation of the product mixture into a hydrocarbon phase containing the carbamate and a polyamine phase containing the polyamine hydrochloride salt utilizes an excess of polyamine reactant containing a limited amount of water. The process is particularly suited to the production of monocarbamate.

BACKGROUND OF THE INVENTION 
This invention relates to the production of polymeric carbamates, in 
particular the continuous production of polymeric carbamates which find 
use as fuel additives. Such fuel additives, as described in our copending 
application Ser. No. 801,441, filed May 27, 1977 now U.S. Pat. No. 
4,160,648, are highly desirable deposit control additives which 
effectively limit the deposits in intake systems (carburetor, valves, 
etc.) without contributing to combustion chamber deposits which cause an 
increase in the octane requirement of the engine. 
Particularly effective additives of this class are monocarbamates produced 
from polyamines and polymeric chloroformates. By "monocarbamates" is meant 
carbamates containing a single polyamine moiety linked at an amine 
nitrogen atom through a carbamate linkage to the oxygen atom of a 
polyether alcohol. In order to produce substantial amounts of 
monocarbamate rather than dicarbamate in which two polymeric alcohol 
moieties are bound to the polyamine at different reactive amine nitrogen 
atoms, it is necessary to use a large excess of polyamine. Because the 
reaction between polyamine and polymeric alcohol goes via a polymeric 
chloroformate intermediate, polyamine hydrochloride is produced in 
equimolar amount to the desired carbamate. Chloride is untenable in 
automotive fuels and causes corrosion and plugging of process equipment 
and should be reduced to very low levels before final separation of the 
monocarbamate product. 
The removal of the hydrochloride salt with recovery of the excess polyamine 
poses formidable problems. Phase separation between a hydrocarbon phase 
containing the carbamate product and a polyamine phase containing the 
hydrochloride salt is a possible procedure. However, the polyamine is in 
general soluble in the hydrocarbon phase so that the use of large excess 
polyamine results in a large hydrocarbon phase and a small 
hydrochloride-containing phase. The hydrochloride-containing phase then 
forms small droplets distributed through the hydrocarbon phase, fails to 
agglomerate and/or settles too slowly to allow continuous operation. 
Washing the product with sufficient water to remove the hydrochloride, or 
a combination of alcohol and water, has been used in the past, but 
produces a polyamine-water-polyamine hydrochloride separation problem 
which is complicated by the large amounts of water present. (If water 
alone is used in washing, it tends to form an emulsion unless some 
low-molecular-weight alkanol is also present. This presents further 
separational complexity.) The complete removal of chloride ion from the 
product is required for efficient separation of the product carbamate by 
distillation and the use of the carbamate in gasoline fuels. A stringent 
upper limit of about 10 ppm or less of chloride ion is specified for the 
hydrocarbon phase containing the carbamate. 
DESCRIPTION OF THE PRIOR ART 
U.S. Pat. No. 3,671,511 describes the process of separating the product of 
the reaction of a polymeric olefin chloride with an amine by charging 
hydrocarbon diluent, an alkanol and water to the product. 
SUMMARY OF THE INVENTION 
In the process of the present invention, advantage is taken of the 
solubility of polyalkylene polyamine, hereinafter called polyamine, in 
water to create an aqueous polyamine hydrochloride phase which separates 
from the hydrocarbon phase easily and quickly enough for continuous 
operation. The rapid separation is accomplished by the addition of a small 
amount of water to a very large excess of polyamine prior to the reaction 
between the polyamine and the polymeric chloroformate. The addition of a 
limited amount of water prevents the dispersion of the 
hydrochloride-containing phase as droplets in the hydrocarbon phase, yet 
produces no emulsion. 
This process for the production of a polymeric carbamate comprises a first 
step of very rapidly contacting and thoroughly mixing at a temperature of 
about 0.degree. to about 150.degree. C. reactant streams of polymeric 
chloroformate and polyamine to form a product mixture. Said reactant 
stream of polymeric chloroformate contains from 20 to 80 weight percent 
polymeric chloroformate in a hydrocarbon solvent. Said reactant stream of 
polyamine contains about 6-35 weight percent water. The mol ratio of 
polyamine to polymeric chloroformate in said streams is from about 5:1 to 
about 45:1. In a second step, said product mixture is allowed to separate 
at a temperature of from about 20.degree. C. to about 120.degree. C. into 
two phases, namely, a hydrocarbon phase principally comprising a 
hydrocarbon solvent, polymeric carbamate and polyamine, and an aqueous 
phase principally comprising water, polyamine and polyamine hydrochloride.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS OF THE INVENTION 
A more comprehensive understanding of the concept of the invention can be 
achieved by reference to the drawing. 
The drawing provides a block-flow diagram of an embodiment of this 
invention. In this embodiment, a polyamine (ethylenediamine) reacts with 
alkylphenol poly(oxybutylene) chloroformate having a molecular weight of 
about 1800. The chloroformate reactant is introduced through line 1 and 
blended in static mixer K-1 with aromatic solvent fed from line 2 in about 
equal amounts by weight. The chloroformate/solvent blend is next sent via 
line 5 to be mixed and reacted with polyamine (containing a limited amount 
of water) from line 4 in static mixer K-2. The polyamine consists of fresh 
made-up polyamine from line 3 and recycled polyamine from the product 
still overhead separator V-6 from line 21. The exothermic reaction of 
chloroformate and polyamine is very rapid and is completed as soon as the 
streams are mixed. Speed of mixing is important to the success of the 
reaction step which has as its object the production of a monocarbamate 
product. The polyamine feed to the reaction mixer K-2 is set by operating 
conditions downstream in the separators V-1 and V-4 rather than the 
requirements of the reaction itself. Under normal operating conditions 
with solvent recycle, the reaction is carried out at a 
polyamine/chloroformate mol ratio of about 20:1. This ratio is set to 
provide sufficient amounts of a polyamine-rich phase for good chloride 
removal downstream in the first separator V-1. When the plant is operated 
without solvent recycle, a polyamine/chloroformate ratio of 30:1 is 
preferred to permit good phase separation in the downstream separators. 
Consequently, the polyamine/chloroformate ratios in the reaction step are 
much higher than necessary to achieve a high yield of monocarbamate. 
Ratios above 5:1 only marginally improve monocarbamate yield as long as 
rapid mixing of polyamine and chloroformate is achieved. The reaction 
mixture from K-2 by way of line 6 is combined with recycle solvent from 
line 7 in static mixer K-3 and sent via line 8 to the first-stage 
separator V-1. The mixture separates in V-1 into relatively clear upper 
and lower phases. The normal operating temperature for the first-stage 
separator V-1 is about 195.degree. F. (90.degree. C.) but higher 
temperatures, e.g., up to about 230.degree. F. (110.degree. C.) may be 
used provided in any case that the pressure is adequate to prevent 
boiling. The water content of the polyamine-rich phase in the separator, 
while not directly controlled at this point, is an important parameter 
effecting separator performance. Under normal operating conditions the 
lower phase in V-1 will contain about 14% water. Both higher and lower 
levels will tend to adversely affect separator performance. A reasonable 
operating range under these conditions is about 11-18% water by weight. 
The density difference between the upper and lower phases in V-1 is very 
small, there being only about 0.05 difference in specific gravity between 
them. Consequently, any temperature gradient in the separator could easily 
have an adverse effect on performance and the vessel is completely 
insulated to minimize heat loss. The hydrocarbon-rich upper phase from the 
separator normally contains about 100 ppm chloride. This upper phase flows 
via line 14 to the second separation stage where chloride is further 
reduced. Most of the free polyamine in the lower phase from V-1 is 
recovered by flashing the lower phase taken via line 9 under vacuum 
conditions in V-2. This polyamine-rich lower phase from the separator V-1 
contains the bulk of the polyamine hydrochloride. The polyamine 
hydrochloride waste stream is removed as the flash bottoms product by line 
10. The collected condensate from V-2 is pumped via line 11 to the 
polyamine wash surge V-3 into which make-up water enters via line 12. 
Residual chloride in the upper hydrocarbon-rich phase from the first-stage 
separator is reduced to less than 10 ppm by washing with polyamine 
containing limited amounts of water, and separating the resultant 
two-phase mixture. Polyamine fed to the wash mixture in K-4 is pumped from 
the polyamine wash surge V-3 via line 13, heated to the separator 
operating temperature (90.degree. C.) and mixed with the product/solvent 
phase from V-1 moving via line 14. The polyamine/product wash mixture from 
K-4 moves from line 15 into the second-stage separator V-4 which normally 
operates at the same temperature as V-1. Phase separation in this second 
stage is more difficult than the first stage due largely to an even 
smaller difference in density between the phases. V-4 is also fully 
insulated. The water content of the polyamine wash to the polyamine wash 
mixer K-4 is normally controlled at about 16 weight percent. Control is 
achieved by monotoring the water content in V-3 and adjusting water 
make-up as required. Control of water content at this point also assures 
that water content of the polyamine feed to the first-stage separator via 
lines 19, 20, 21 and 4 is correct. The performance of both the first- and 
second-stage separators is optimized by water content of about 16 weight 
percent water in the polyamine stream. A preferred operating range is 
about 13-20 weight percent water. The upper phase from V-4 flows by way of 
line 16 to the product still V-5. The product still removes polyamine and 
water from the final product in order to meet the specifications for 
water-soluble base and water content. Vacuum operation is achieved by 
pulling a vacuum at line 22. The overhead from the product still (line 17) 
consisting of polyamine, solvent and water, and the lower polyamine-rich 
phase from the second-stage separator (line 18) are combined with the 
polyamine wash bypass from V-3 (line 19) and are pumped by way of line 20 
to the product still overhead separator V-6 where phase separation is 
accomplished. The upper solvent phase in V-6 provides solvent recycled 
through line 7 to be mixed with the reaction mixture in static mixer K-3. 
The lower polyamine phase in V-6 from line 21 is combined with make-up 
polyamine from line 3 and pumped to the front end to provide the polyamine 
feed to reaction mixture K-2. The net bottoms product from the product 
still exits at line 23. 
REACTANTS 
The polymeric chloroformate is a hydrocarbyl-capped poly(oxyalkylene) 
chloroformate of molecular weight from about 500 to about 10,000, 
preferably from about 500 to 5000. The hydrocarbyl-capped 
poly(oxyalkylene) polymers are monohydroxy compounds, i.e., alcohols, 
often termed monohydroxy polyethers. Hydrocarbyl-terminated 
poly(oxyalkylene) alcohols are produced by the addition of lower alkylene 
oxides, such as propylene oxide, to a hydroxy compound, ROH, under 
polymerization conditions, wherein R is a C.sub.1 -C.sub.30 alkyl, aryl, 
or alkaryl group. Preferably, the polymeric chloroformate is formed from 
the aforesaid polymers by reacting a hydroxyl-containing polymer with 
phosgene. A preferred polymeric chloroformate is an alkylphenyl-capped 
poly(oxyalkylene) chloroformate, such as dodecylphenyl poly(oxybutylene) 
chloroformate. Preferably, the oxyalkylene units are selected from C.sub.2 
-C.sub.5 oxyalkylene units such as are provided by oxirane, methyloxirane, 
ethyloxirane and propyloxirane. 
The polyamine is water soluble. It contains from 2 to 10 carbon atoms and 
from 2 to 5 nitrogen atoms, preferably from 2 to 6 carbon atoms and from 2 
to 4 nitrogen atoms. At least one of the amino nitrogens in the polyamine 
is a primary or secondary amino nitrogen. Mixtures of polyamines may also 
be used. The polyamine may be substituted with hydrogen, lower hydrocarbyl 
groups, or other substituents selected from lower acyl, keto, hydroxy, 
nitro, and cyano groups. Preferably the polyamine is a polyalkylene 
polyamine, wherein the alkylene is a C.sub.2 -C.sub.6 alkylene group, such 
as ethylenediamine, diethylenetriamine, triethylenetetraamine, 
tetraethylenepentamine, dimethylaminopropyl amine, 
N-(2-hydroxyethyl)diethylenetriamine, propylenediamine, 
dipropylenetriamine, tripropylenetetra-amine, etc. More preferably the 
polyalkylene polyamine is an ethylene or propylene polyamine such as 
ethylenediamine or dipropylenetriamine, and ethylenediamine is the most 
preferred. 
The solvent is generally a hydrocarbon solvent. Generally, aromatic 
solvents of from 6 to about 16 carbon atoms are used and aromatic solvents 
of from 8 to 10 carbon atoms are preferred. Such solvents are exemplified 
by the xylenes, ethylbenzene, and cumene or other C.sub.9 -C.sub.10 
alkylbenzenes. 
PROCESS CONDITIONS 
The process of the present invention may be practiced continuously or in 
batches. In the process of this invention a reactant stream of said 
polymeric chloroformate is very rapidly contacted and thoroughly mixed 
with a reactant stream of said polyalkylene polyamine at a temperature of 
from about 0.degree. C. to about 150.degree. C. for the purpose of forming 
the product polymeric carbamate. Rapid thorough mixing is accomplished by 
using a static in-line mixing assembly. The duration of mixing is also 
important since contact time must be sufficient to permit the 
hydrochloride to transfer from the polyether aminocarbamate product to the 
polyamine in a secondary reaction step. Without sufficient mixing time, 
excessive chloride ion remains in the hydrocarbon phase after the 
water-containing polyamine hydrochloride phase has separated from it. 
Peferably a reaction temperature of from about 20.degree. C. to 65.degree. 
C. is used. Most preferably the reaction temperature is about 25.degree. 
C. The reactant stream of polymeric chloroformate contains about 20-80 
weight percent of polyamine chloroformate, the remainder being made up of 
said hydrocarbon solvent. Preferably about 40-60 weight percent polymeric 
chloroformate is found in said reactant stream. The polyamine reactant 
stream contains from about 65 to about 94% polyamine, the remainder being 
made up of water, i.e., 35-6 weight percent water. 
Surprisingly, the water has no apparent effect on the reaction, either as 
to rate of reaction or yield of carbamate. A small amount of water in a 
limited range is needed, because while insufficient water results in too 
small an aqueous hydrochloride-containing phase and poor chloride removal, 
too much water causes haziness and poor phase separation. Preferably about 
80 weight percent to 90 weight percent amine and 20 weight percent to 
about 10 weight percent water is used. Amounts of water below about 6 
weight percent allow too much chloride to reach the final product 
distillation, while amounts greater than about 35 weight percent or more 
produce increasing amounts of haze which indicates poor separation. 
The mol ratio of polyamine to polymeric chloroformate in said reactant 
streams is from about 5:1 to about 45:1, preferably from about 10:1 to 
30:1. 
The thoroughly mixed product mixture comprising polymeric carbamate and 
excess polyamine as well as hydrocarbon solvent, water and an amount of 
polyamine hydrochloride equimolar to carbamate, is drawn into a settling 
vessel (separator) where the hydrochloride- and water-containing polyamine 
phase is permitted to separate from the lighter hydrocarbon phase. Because 
of the polymeric nature of the product carbamate in the upper hydrocarbon 
phase, improper feed mixtures can produce a high viscosity upper phase 
which hinders separation and removal of chloride. Likewise, improper feed 
mixtures which result in small density diferences between the phases, or 
emulsions, or small chloride-containing phase volume relative to the upper 
phase volume, can also hinder phase separation. Consequently, separation 
temperatures and amounts of materials present, particularly the amount of 
water present, are critically selected to avoid these conditions. The 
optimum amount of water present is also related to the temperature of 
separation. At a separation temperature of about 90.degree. C., water 
contents in the polyamine phase greater than about 35 weight percent 
causes too slow a separation, while less than 2 weight percent water in 
the polyamine phase does not yield a large enough chloride and 
water-containing polyamine phase. Generally, temperatures of about 
80.degree. C. and higher (up to 110.degree. C.) are preferred for 
separation, e.g., about 90.degree. C. is most preferred, but generally 
separation occurs at 20.degree. C.-120.degree. C. Surprisingly, the 
process can be run continuously because of the short time needed for 
separation at about 90.degree. C. with 10-20 weight percent water in the 
polyamine reactant stream to the reaction mixer. 
In a preferred embodiment of the present invention two separations are used 
to insure low residual chloride in the hydrocarbon phase. After an initial 
separation, the chloride- and water-containing polyamine phase is sent to 
a flash distillation vessel. It is to be understood that other polyamine 
recovery systems are usable within the scope of the present invention so 
that this choice of the polyamine recovery system is not limiting. A 
portion of the overhead from the flasher is combined with the hydrocarbon 
phase from the first separator and thoroughly mixed. The overhead contains 
polyamine and a limited amount of water so that the mixing serves to wash 
chloride from the hydrocarbon phase. This wash mixture is sent into a 
second stage of separation. This separation is effected over a similar 
range of temperature and water content as for the initial separation. 
Preferably the polyamine wash stream to the interstage wash mixer contains 
about 10-20 weight percent water and the separation is preferably 
performed at about 80.degree. C.-110.degree. C. In the second stage 
separator the water content of the mixture is even more critical than in 
first-stage separation in order to obtain phase separation. Too large a 
water content of the polyamine stream leads to increasing emulsification, 
but at too low water concentrations, depending on the particular 
polyamine, the solvent composition and concentration, the type of 
polyether aminocarbamate, and the temperature, the two phases will have 
equivalent densities and will not separate at all. In a preferred case of 
an ethylenediamine wash, wherein the product phase comprises 50 weight 
percent of C.sub.9 -C.sub.10 aromatic solvent and an alkylphenyl 
poly(oxybutylene) aminocarbamate of about 1800 molecular weight, 
equalization of phase densities occurs at about 6-8 weight percent water 
at 80.degree. C. When the water concentration is too low the polyamine 
phase remains suspended as droplets or large drops in the product/solvent 
phase. 
The hydrocarbon phase from the second separator is sent directly to a 
product still from which the final product carbamate is obtained as a 
bottoms product. The use of two stages of separation with thorough 
interstage washing with a polyamine-water stream serves to reduce the 
chloride concentration in the hydrocarbon phase to less than about 10 ppm. 
Very low levels of chloride are preferred to prevent corrosion and 
plugging of the still. 
EXAMPLES 
The following examples are based on experiments carried out in the 
laboratory and in part on pilot plant demonstration of key steps in the 
process. All parts are given as parts by weight per hour. 
EXAMPLE 1 
2,666 parts by weight of mixed didodecylphenyl and dodecylphenyl ether of 
poly(ethyloxirane) chloroformate, having an average of 15 butylene oxide 
groups per molecule, is combined at 60.degree. F. with 2,666 parts of a 
C.sub.9 -C.sub.10 aromatic solvent in an in-line static mixer. This 
mixture is subsequently mixed with 2,056 parts of a water-containing 
ethylenediamine (EDA) stream in a second static mixer, the reaction static 
mixer, which achieves nearly instantaneous mixing. The ethylenediamine 
contains 216 parts of fresh make-up ethylenediamine and 1,521 parts of 
recycle diamine from a product still overhead separator. Sufficient water 
is contained in the recycle stream to give a final water concentration of 
about 11% water by weight relative to ethyelendiamine in the EDA stream. 
The remainder of the EDA stream is made up of a small amount of solvent 
which is soluble in the recycled EDA. Complete and thorough mixing of the 
reactant stream takes place in the static mixer, and after an additional 
residence time, the crude product stream is removed and combined with 
1,015 parts of recycled solvent itself containing 6.5 weight percent 
ethylenediamine. The resulting mixture, 8,403 parts, containing 2.7 weight 
percent water, is then charged to the first separator. The first separator 
is maintained at 90.degree. C. Separation takes place rapidly and the 
lower phase, 1,326 parts, is withdrawn to a flash distillation vessel. 
This lower phase contains 14 weight percent water in a mixture consisting 
primarily of 145 parts of ethylenediamine hydrochloride and 938 parts of 
ethylenediamine. The remainder is mainly solvent. The upper phase, 7.077 
parts, is withdrawn for mixing with an EDA wash stream. This upper phase 
contains 2,686 parts of product, 3,650 parts of solvent, two parts of 
ethylenediamine hydrochloride, and 696 parts of unreacted ethylenediamine. 
The water content of the upper phase is only about 0.5 weight percent. The 
lower phase is charged through a flash distillation vessel operating at 4 
psia with a bottoms temperature of 245.degree. F. The high-boiling 
residue, 196 parts, withdrawn from the flasher contains the 
polyaminehydrochloride, as well as two parts of product, and 40 parts of 
ethylenediamine. This bottoms material is sent to disposal or can be 
further treated for additional diamine recovery. Removal of additional 
ethylenediamine by simple vaporization results in crystallization of the 
stream and makes handling difficult. The overhead portion from this 
flasher, 1,130 parts, is removed and charged to a surge vessel. A portion 
of the material in the surge vessel, 794 parts, containing 79 weight 
percent ethylenediamine, 5% solvent and 16% water, is combined with the 
upper phase from the first separator in a static mixing device. The 
combined upper phase and wash streams, 7,871 parts, containing 2% water, 
is charged to the second separator, maintained at 90.degree. C. In this 
separator the remaining hydrochloride, two parts, is withdrawn with the 
lower phase, 639 parts, to be combined with the excess EDA from the surge 
tank. This stream also contains 489 parts of ethylenediamine and 118 parts 
of water (18.5 weight percent), the remainder being solvent and product. 
After combining this lower phase with the excess from the surge vessel, 
the combined stream is sent to the product still overhead separator. 
The upper phase from the second separator, 7,232 parts, is charged to a 
distillation column. This column is maintained at the top at 160.degree. 
F. and 2.5 psia by a vacuum system. A small amount, approximately 11 
parts, of water, solvent, and ethylenediamine is lost through the vacuum 
system. The column has a bottoms temperature of 265.degree. F. at about 4 
psia pressure. The bottoms fraction, 5,348 parts, from this distillation 
column contains 2,685 parts of product in the aromatic solvent. A 
condensed distillate fraction removed from the column contains 1,001 parts 
of solvent, 834 parts of ethylenediamine and 49 parts of water. This 
fraction is charged to theoverhead separator. The overhead separator is 
operated at about 100.degree. F. The upper layer, 1,015 parts of recycle 
solvent is recycled back to dilute the reaction mixture entering the first 
separator. The lower layer, containing recycle EDA, is combined with fresh 
make-up ethylenediamine before charging to the reaction static mixer. The 
final product contains about 50% solvent and less than 7 ppm chloride. 
Only about 3 weight percent of the final product is the dicarbamate of 
ethylenediamine. The product contains about 0.05 weight percent water and 
the active component (about 47 weight percent) is essentially identical to 
the mixed didodecylphenyl and dodecylphenyl ethers of 
poly(ethyloxirane)-mono-[N-(2-aminoethyl)carbamate] prepared by batch 
methods. 
EXAMPLE 2 
Operating parameters varied widely during successful test runs of a pilot 
plant constructed according to the present invention. Typical approximate 
operating conditions for one run on ethylenediamine (EDA) and 
alkylphenylpoly(oxybutylene) dichloroformate of about 1800 molecular 
weight in a C.sub.8 -C.sub.10 aromatic solvent are found in Table 1 and 
compositions for such a run in Table 2. 
TABLE 1 
______________________________________ 
Chloroformate Feed Rate, ml/Min. 
60-80 
EDA Feed Rate, ml/Min. 45-60 
EDA/Chloroformate Mole Ratio 
10:1 to 
20:1 
Water Contents of EDA, wt % 
6-10 
Temperature of Separators I and II, .degree.C. 
93 
Product Still 
Overhead Pressure, Torr 92 
Pressure Drop, Torr 10-12 
Temperature, .degree.C. 
Feed 77 
Bottoms 110 
Product Distillate, ml/Min. 
80 
Product Bottoms, ml/Min. 
20 
EDA Flash Unit 
Pressure, Torr 220 
Temperature, .degree.C. 121 
Feed Rate, ml/Min. 40-60 
Bottoms Product Rate, ml/Min. 
2.5 
______________________________________ 
TABLE 2 
__________________________________________________________________________ 
Stream.sup.1 
% EDA 
% Cl.sup.- 
% H.sub.2 O 
% Solvent 
% Product 
% Basic N 
% N 
__________________________________________________________________________ 
Upper Phase Separator 1 
13.00 
32 ppm 
0.64 
51.60 34.76 
Lower Phase Separator 1 
68.65 
3.64 16.90 
10.81 
EDA Flasher Overhead 
75.09 
&lt;14 ppm 
19.42 
5.49 
Upper Phase Separator 2 
12.14 
&lt;14 ppm.sup.2 
0.70 
51.56 35.60 
Lower Phase Separator 2 
71.66 
446 ppm 
16.82 
11.48 
EDA Flasher Bottoms 
64.39 
28.13 4.26 
3.22 
Product Still Overhead 
72.95 
&lt;14 ppm 
3.34 
23.71 
EDA Input to Reaction 
Mixer 81.96 
342 ppm 
11.82 
6.19 
Product Still Bottoms 
3 ppm 
0.04 
59.60 40.36 0.29 0.52 
__________________________________________________________________________ 
.sup.1 EDA/Chloroformate Mole Ratio approximately 20:1 All components by 
weight % unless ppm. 
.sup.2 Subsequent work on a more efficient semiworks separator has 
demonstrated &lt;10 ppm Cl.sup.- is achievable at this point.