Co-catalytic method for obtaining improved chlorination of phenols

In a process for producing relatively pure commercially acceptable pentachlorophenol, comprising reacting, at a temperature ranging from about 10.degree. to about 190.degree. C., (A) a phenol consisting essentially of raw or commercial phenol which may contain, as impurities from other processes, some lower chlorophenols such as mono and dichlorophenols and mixtures thereof, and (B) chlorine, in the presence of (C) an acid catalyst from about 0.005 moles to about 0.016 moles per mole of (A) used, consisting essentially of aluminum chloride, ferric chloride, metal iron, aluminum tributoxide, antimony chloride, metallic antimony, stannous chloride, metallic tin, cuprous chloride and metallic copper; the improvement consisting of using (D) a sulfur containing co-catalyst selected from the group consisting of sulfur, thiophenol, para-chlorothiophenol, para, para'-dichlorophenyl sulfide, sodium hydrosulfide, 2,2'-thiobis (4,6-dichlorophenol) benzyl disulfide, dibenzothiophenol, benzyl-disulfide, diphenyl sulfide, diphenyl disulfide, di-isopentyl sulfide, naphthalene thiol, heptyl sulfide, hexochlorophenyl sulfide, dicresyl disulfide, dihexadecyl sulfide and dibenzothiophenol thiophenol, wherein components (A) and (B) constitute the sole reacting ingredients and components (C) and (D) constitute the catalytic system for promoting the reaction of components (A) and (B).

This invention relates to the use of a novel co-catalyst in conjunction 
with acid catalysts generally used in producing chlorinated phenols. These 
novel co-catalysts consist of one or more sulfur containing compounds such 
as thiophenol and diphenyl sulfide used generally in extremely small 
amounts. 
Some of the advantages gained include reduced chlorination times, increased 
manufacturing safety by reducing the risk of unexpected and violent 
evolution of hydrochloric acid and increased yields of the desired 
chlorinated product. Furthermore, starting materials may include phenols 
which are otherwise difficult or impossible to chlorinate using standard 
catalysts and conditions. 
This invention relates to an improved method of preparing relatively pure 
higher chlorinated phenols and especially pentachlorophenol by catalytic 
means. Among the benefits realized are a reduction of impurities such as 
chlorinated dibenzo-p-dioxins and chlorinated dibenzofurans. In the 
previously described processes for chlorination of phenols or partially 
chlorinated phenols to form higher chlorinated phenols such as 
pentachlorophenol, the customary practice is to employ such catalysts as 
metal aluminum chloride, aluminum, antimony pentachloride, ferric chloride 
and iodine. Following chlorination, the molten chlorophenols are pumped to 
heated storage pending flaking, prilling, or molding operations necessary 
to change the product to a form acceptable for end use. Some of the 
specifications for industrial chlorinated phenols valuable for fungicidal 
activity are low alkali insoluble content, low insolubles in alkane 
solvents as well as, in the case of pentachlorophenol, a minimum of 86% 
pentachlorophenol content. 
The use of aluminum chloride alone works adequately in most instances, 
however, there is encountered from time to time in manufacture of 
particular batches, depending on the source or quality of the raw 
materials, a problem of unreactivity leading to prolonged chlorination 
time and the usual consequences of lowered quality of the final product 
and the danger of a sudden explosive release of hydrochloric acid gas 
during chlorination. 
It has been found that re-distilled lower chlorinated phenols in particular 
give chlorination problems in their employment as raw material for 
manufacture of pentachlorophenol and frequently different supplies of 
phenol vary in time required to chlorinate them to higher chlorinated 
phenols. In some instances, it is impossible to successfully chlorinate 
phenol into acceptable pentachlorophenol without the use of our invention. 
It is among the objects of this invention to provide a process whereby 
relatively pure commercially acceptable higher chlorinated phenols such as 
pentachlorophenol are produced under safe operating conditions at all 
times by use of a powerful catalyst system and wherein the desired product 
specifications can be met. It is also an object of this invention to 
reduce the polymeric by-products normally present in higher chlorinated 
phenols such as pentachlorophenol. A number of co-catalysts were used in 
conjunction with aluminum chloride and were evaluated to discover more 
effective catalyst systems. Initially, combinations of aluminum chloride 
and other metallics were tried as co-catalysts. Experiments were conducted 
by adding nickel chloride along with the usual aluminum chloride to a 
nonreactive batch of phenol and chlorinating to obtain pentachlorophenol. 
No beneficent effect could be noted by adding the nickel compound and, in 
fact, the reaction would not be completed. In another experiment, ferric 
chloride was added along with the aluminum chloride. It was observed that 
the ferric chloride addition did help in the reaction since less chlorine 
was by-passed in the off-gas vent. The reaction time was still 9.5 hours 
as compared to the control of 9.5 to 10.5 hours; a small gain in the 
reaction time. It was also observed that ferric chloride gave rise to more 
alkali insolubles in the final product. When ferric chloride was tried in 
the plant, the advantage gained was insufficient to relieve the problem of 
unreactive phenol or partially chlorinated phenols in batches used as the 
starting material for the manufacture of pentachlorophenol. In other 
experiments, copper and zinc salts were tried without significant success. 
Because of this limited success in finding a successful metallic 
co-catalyst, we were surprised to find that thiophenol, when added with 
anhydrous aluminum chloride, significantly reduced the reaction time. In 
addition, it was discovered that dangerous dips were avoided in the plant 
process. Further investigation of this phenomenon revealed that thiophenol 
alone will not catalyze chlorination of phenols to higher chlorinated 
phenols. It is theorized, after this discovery, that the thiophenol in 
some way formed a complex with aluminum chloride; this complex being a 
powerful chlorinating catalyst. Other explanations could be possible. 
Investigation of the literature revealed that thiophenol in the presence 
of aluminum chloride forms diphenyl sulfide and thus it was probably this 
particular sulfur compound that we were mainly concerned with when 
attempting to elucidate reasonable mechanisms that can explain its role in 
the chlorinating reaction. We further realized that during chlorination, 
diphenyl sulfide would, itself, be chlorinated on the ring structure; for 
instance, to tetrachlorodiphenyl sulfide. 
It would appear from the above considerations and background that when 
diphenyl sulfide is added along with aluminum chloride in the reaction 
mixture at some time during the reaction, the chlorinated diphenyl 
sulfide-aluminum chloride molecular addition compound is formed. This can 
be regarded as a metal ligand bond, as for example, shown below: 
##STR1## 
The commonly accepted mechanism for aromatic halogenation in the presence 
of aluminum or iron chloride implies the chlorinating agent is the 
chlorinium ion (Cl+); this particular species being necessary for the 
reaction to proceed. 
It is possible that the high chlorinating activity demonstrated in our 
invention may be due to the formation of relatively high concentrations of 
the chlorinium ion from the interaction of a sulfide-aluminum chloride 
complex with chlorine as in the example on the following page. 
##STR2## 
Other explanations for the powerful and unique chlorinating activity of the 
catalyst systems of our invention may also be devised, but these 
considerations which were not obvious prior to our catalyst discovery do 
not detract from the scope and utility of this discovery. 
Through use of our invention, it is now possible to manufacture highly 
chlorinated phenols such as pentachlorophenol in shorter reaction times 
with improved quality of the product. Still another important benefit is 
avoidance of "dips" when the chlorination reaction virtually ceases 
followed by violent evolution of hydrochloric acids. In plant process, 
danger to life of the workers arises when a batch erupts during a bad 
"dip". 
Normally, chlorine time reactions may be carried out with or without a 
solvent at temperatures gradually increasing up to about 190.degree. C. 
The preferred amount of catalyst which we employ is from about 0.0001 
moles to about 0.02 moles of the sulfide, sulfur or sulfhydryl and from 
about 0.001 to about 0.004 moles of aluminum chloride per mole of phenol 
or partially chlorinated phenol starting material. However, it has been 
found that from between 0.000015 moles and about 0.2 moles of the sulfide, 
sulfur or sulfhydryl may be used and from about 0.0005 to about 0.016 
moles of aluminum chloride per mole of phenol or partially chlorinated 
phenols may be used. 
As well as aluminum chloride, other forms of aluminum can be employed in 
the practice of this invention such as aluminum metal itself or organic 
compound of aluminum. Aluminum and/or its derivatives revert to or form 
aluminum chloride by chemical reaction with elemental chlorine which is 
introduced into the reactor during the manufacturing process. In addition, 
the following metal catalysts may be used in place of aluminum metal or 
aluminum chloride in essentially the same amount: ferric chloride, metal 
iron, aluminum tris-butoxide, antimony chloride, metallic antimony, 
stannous chloride, metallic tin, cuprous chloride and metallic copper. 
Typical sulfur bearing compounds that can be used as part of this invention 
include sulfur, diphenyl sulfide, diphenyl disulfide, dicresyl disulfide, 
dihexadecyl sulfide and dibenzothiophenol thiophenol, 
parachlorothiophenol, para, paradichlorophenyl sulfide, sodium 
hydrosulfide, 2,2'-thiobis (4,6-dichlorophenol) benzyl disulfide, 
diisopentyl sulfide, naphthalene thiol, heptyl sulfide and 
hexachlorophenyl sulfide. 
As previously stated, another object of this invention is to provide a 
process for producing pentachlorophenol containing considerably reduced 
amounts of undesirable polymeric impurities. Among these are certain 
chlorinated dibenzodioxins and chlorinated dibenzofurans that normally 
occur in the regular manufacturing processes. These chlorinated 
dibenzodioxins have been considerably studied and occur in the range of 
100 to 5000 parts per million total in commercial technical grade 
pentachlorophenol. This mixture of chlorinated dibenzo-p-dioxins has been 
analyzed and found to consist of hexachlorodibenzo-p-dioxins (2 isomers, 
the 1,2,3,7,8,9 and 1,2,4,6,7,9-hexachlorodibenzo-p-dioxins), 
heptachlorodibenzo-p-dioxin (2 isomers, the 1,2,3,4,6,7,8 and 
1,2,3,4,6,7,9-heptachlorodibenzo-p-dioxins), and 
1,2,3,4,6,7,8,9-octachlorodibenzo-p-dioxins. The most toxic chlorinated 
dibenzo-p-dioxin, the 2,3,7,8-tetrachlorodibenzo-p-dioxin was not found to 
be present in any instance. Following the practice of our invention, the 
total amounts of all chlorinated dibenzo-p-dioxins are reduced on the 
average to about 40% of the control, the hexachlorodibenzo-p-dioxins were 
reduced on the average to 24% of the control, the 
heptachlorodibenzo-p-dioxins were reduced on the average to 41% of the 
control, and the octachlorodibenzo-p-dioxin was reduced on the average to 
55 % of the control. The control is commercial technical grade 
pentachlorophenol. 
Also, the chlorinated dibenzofuran concentrations in pentachlorophenol are 
reduced by practice of our invention. In this instance, the 
heptachlorodibenzofurans (isomers not elucidated) were reduced 20-40% 
compared to the control and 1,2,3,4,5,6,7,8-octachlorodibenzofuran was 
reduced about 70-94% as compared to the control. 
Typically, chlorinations are carried out in a glass vessel equipped with a 
stirrer, heating mantle, cooling system, a thermometer, a chlorine feed 
line with a sintered glass diffuser and an exit line for hydrochloric acid 
vapor. Chlorine is fed from a chlorine cylinder to which a reducing valve 
was attached. A manometer containing carbon tetrachloride is connected 
across an orifice as a flow meter. 
One kilogram samples of low reactive phenol or partially chlorinated low 
reactive phenol plus about 2.8 grams of anhydrous aluminum chloride or its 
mole equivalent of aluminum metal and 0.0001 to 0.2 moles of the sulfur or 
sulfur containing co-catalyst were heated to 120.degree. C. and 
chlorinated to pentachlorophenol with stirring. The chlorine feed was 
regulated so that by-passing was minimized. The temperature was increased 
slowly to keep the batch molten until the freezing point reached about 
178.degree.-183.degree. C. The batch was then poured out and quenched by 
solidification. The total time of chlorination and other characteristics 
of the batch were noted and placed in Table I. Variations of this 
procedure may be carried out, within keeping of the state of the art, but 
we found this procedure sufficiently useful for obtaining the necessary 
data. In other experiments, plant size batches were run in about the same 
manner as in the laboratory. The partially chlorinated phenols used for 
the experiments had been previously distilled and were found to be 
unreactive for the normal process of making pentachlorophenol with use of 
aluminum chloride catalyst alone.

The following examples illustrate the advantages and unexpected results 
which are achieved by use of the catalytic agents of this invention, but 
it is not intended that this invention be limited by or to the examples. 
Examples I, II, III and IV were designed to give a comparison of the time 
taken to successfully complete chlorination of phenols to produce 
pentachlorophenol. 
EXAMPLE I 
In the 2000 ml vessel with other equipment as described 1000 grams of 
feedstock (particularly unreactive and partially chlorinated phenol), 2.8 
grams of anhydrous aluminum chloride and 3.9 grams of diphenyl sulfide 
were heated to 120.degree. C. and the chlorine was sparged in at a rate so 
that the by-passing of unreacted chlorine was minimized. The batch was 
heated slowly so that the temperature was 5 to 10.degree. C. above the 
freezing point of the batch at any time. Samples of the batch were 
withdrawn from time to time and the freezing points taken and recorded. 
When the freezing point reached about 181.degree. C., chlorination was 
stopped and the product poured out. No difficulty was encountered in 
completing this reaction which took 6 hours. In this example, the 6 hour 
recorded chlorination time is low compared to other experiments where 
sulfides were not used in conjunction with aluminum chloride. The low 
chlorination time indicates that the catalyst system is very effective and 
powerful whereas longer reaction time would indicate less effectiveness. 
EXAMPLE II 
In the same equipment as described in Example I, a mixture of 1000 grams of 
the same feedstock as in Example I, 2.8 grams of anhydrous aluminum 
chloride and no diphenyl sulfide was chlorinated as before. Unlike Example 
I, the chlorine feed rate had to be kept lower throughout the reaction 
because of extensive chlorine by-passing due to phenol unreactivity. Thus, 
the time for the reaction to come to completion (freezing point 
179.5.degree. C.) was 101/2 hours. 
EXAMPLE III 
In the same equipment as described in Example I, a mixture of 1000 grams of 
the same feedback, 2.8 grams of anhydrous aluminum chloride, a 0.150 grams 
of ferric chloride was chlorinated in a manner similar to Example I to 
obtain a pentachlorophenol product with a freezing point of 178.6.degree. 
C. The reaction time was 93/4 hours. 
EXAMPLE IV 
This was a series of experiments primarily testing the effects of sulfur 
based co-catalysts. They were run under similar conditions (as in Example 
I) except that the co-catalysts are varied. The effect of these 
co-catalysts are readily seen in Table I, the column "Total Chlorination 
Time" where shorter reaction time indicates a more powerful catalyst 
system. The amount of phenolic starting material and aluminum chloride is 
the same as in Example I, 1000 grams and 2.8 grams respectively. A variety 
of sulfur compounds as well as sulfur itself and a number of metallic 
salts are included in these summarized experiments. The amount of sulfide 
type co-catalysts are listed in Table I. The results shown in Table I 
demonstrate that a combination complex catalyst consisting of sulfur or 
sulfur bearing compounds with metallic catalysts such as aluminum chloride 
is a highly effective co-catalyst system for chlorination of phenols. 
TABLE I 
__________________________________________________________________________ 
LABORATORY RATE STUDY OF PREATION OF 
PENTACHLOROPHENOL USING VARIOUS TEST CO- 
CATALYSTS WITH ALUMINUM CHLORIDE 
FREEZING POINT 
CO-CATALYST FINAL OF PENTA- 
TOTAL CHLORINATION 
NAME GRAMS 
CHLOROPHENOL .degree.C. 
TIME, HOURS 
__________________________________________________________________________ 
1 (Control) 
-- 179.5 101/2 
none 
2 thiophenol 
4.68 179.0 63/4 
3 thiophenol 
2.36 179.0 6 
4 thiophenol 
1.20 178.0 7 
5 thiophenol 
1.00 179.0 53/4 
6 thiophenol 
0.50 178.0 63/4 
7 thiophenol 
0.10 181.0 61/2 
8 thiophenol 
0.01 178.0 9 
9 p-chloro- 
5.00 179.0 6 
thiophenol 
10 
p-chloro- 
0.50 180.0 73/4 
thiophenol 
11 
p,p'-dichloro 
0.14 183.0 6 
phenyl sulfide 
12 
sodium hydro- 
0.50 180.0 61/2 
sulfide 
13 
2,2'-thiobis 
0.10 181.5 71/2 
(4,6-dichloro- 
phenol) 
14 
(Control) 
-- 181.0 91/2 
none 
15 
Bis(dimethyl- 
0.13 181.0 71/2 
0-thiocarbamoyl) 
disulfide 
16 
dibenzothiophene 
0.10 180.5 71/2 
17 
benzyl-disulfide 
0.13 181.0 8 
18 
diphenyl sulfide 
1.40 181.0 61/2 
19 
diphenyl sulfide 
1.10 181.0 61/4 
20 
diphenyl sulfide 
3.90 181.0 6 
21 
diisopentyl 
0.19 181.0 63/4 
sulfide 
22 
naphtalene 
0.17 181.0 63/4 
thiol 
23 
heptyl sulfide 
0.12 180.5 63/4 
24 
sulfur 0.02 181.0 61/2 
25 
hexachloro- 
0.22 181.0 71/2 
phenyl sulfide 
26 
ferric chloride 
0.150 
178.6 81/3 
27 
ferric chloride 
0.075 
178.6 83/4 
28 
nickel chloride 
0.15 -- --* 
29 
zinc chloride 
0.15 177.1 93/4 
__________________________________________________________________________ 
*Reaction failed to continue after 41/4 hours and therefore, discontinued 
 
EXAMPLE V 
In this series of experiments, pentachlorophenol was prepared on a plant 
scale using from 7500 to 9000 pounds of phenol and/or partially 
chlorinated phenol as starting material. The conditions were essentially 
the same as those used for the laboratory batches but on a larger scale. 
Table II gives details of the experiments and results of the tests 
performed on the final pentachlorophenol product. Considerable improvement 
was observed in the runs where the co-catalyst of this invention, the 
sulfur derivatives, were used; as for example, in less chlorination time 
required and less insolubles being produced. In these experiments, about 
20-70 pounds of aluminum chloride were used per batch. The type of 
phenolic starting material varied wherein only the unreactive phenol was 
used (A) or a combination of an unreactive and reactive phenol (B) was 
used, depicted as (A+B) in Table II. 
EXAMPLE VI 
In this set of experiments, in the plant the phenolic chlorination scale 
and conditions were set the same as for Example V where 7500 to 9000 
pounds of phenol and/or partially chlorinated phenol was utilized as 
starting material. The aluminum chloride was the same as that described in 
Example V while the amounts of the sulfide co-catalyst were varied as 
described in Table III. It was observed that with the use of a sulfide or 
sulfur containing compound, the amounts of objectionable chlorinated 
dibenzo-p-dioxins were reduced by the following percentages as compared to 
commercial technical grade pentachlorophenol. The total kinds of 
chlorinated dibenzo-p-dioxins reduced 49%; the hexachlorodibenzo-p-dioxins 
reduced 24%; the heptachlorodibenzo-p-dioxins reduced 41%. Details of the 
Example VI experiments are shown in Table III. 
TABLE II 
__________________________________________________________________________ 
STUDY OF PLANT BATCHES OF PENTACHLOROPHENOL 
WITH AND WITHOUT USE OF CO-CATALYST 
PHENOLIC FREEZING 
STARTING CO-CATALYST.sup.b 
POINT CAUSTIC TOTAL REACTION 
BATCH 
MATERIAL AMOUNT 
OF FINAL 
INSOLUBLE 
CHLORINATED 
HEXANE TIME, 
NO. TYPE TYPE LBS. PRODUCT 
%.sup.c PRODUCT.sup.d 
TEST.sup.e 
HOURS 
__________________________________________________________________________ 
31-2-468 
A+B.sup.a 
none -- 178.9 0.40 96.9 Heavy ppt. 
19 
before 20 
minutes 
34-2-468 
A+B none -- 179.9 0.33 96.7 " 191/2 
37-2-468 
A+B none -- 179.0 0.50 95.92 " 19 
29-2-568 
A+B none -- 179.5 0.46 96.8 " 19 
31-2-568 
A+B none -- 179.5 0.80 96.24 " 19 
34-2-668 
A+B none -- 178.0 0.60 96.00 " 19 
6-2-768 
A.sup.a 
none -- 180.3 0.23 96.3 " 24 
8-2-768 
A none -- 179.9 0.77 96.8 " 211/2 
14-2-769 
A diphenyl 
1 179.0 0.18 97.5 OK 163/4 
disulfide 
16-2-769 
A " 1 179.0 0.18 97.3 OK 161/2 
18-2-769 
A diphenyl 
1 179.0 0.32 97.3 OK 17 
disulfide 
27-2-269 
A thiophenol 
3/4 179.5 0.10 96.8 OK 16 
44-2-269 
A " 3/4 179.5 0.10 96.8 OK 16 
49-2-269 
A+B " 3/4 179.0 0.14 96.5 OK 16 
45-2-269 
A " 3/4 179.8 0.14 96.5 marginal 
17 
__________________________________________________________________________ 
.sup.a A = Penta feed stock which is obtained as products from 
distillation of chlorinated phenols. This material is known to be 
unreactive for preparing pentachlorophenol. 
B = Recycle phenol is ordinary phenol directly obtained from tank cars an 
mono chlorinated in a side reactor just prior to chlorination to 
pentachlorophenol in the main reactor. 
A+B = Combination of A and B. 
.sup.b About 20-70 lbs. of aluminum chloride are used as co-catalyst in 
chlorination of about 8,500 lbs. of the phenol. 
.sup.c The alkali-insoluble matter in pentachlorophenol is determined in 
the following way: Dissolve a 1-gram sample in 50 milliliters of N/1 NaOH 
and 50 milliliters of distilled water, warming to about 60.degree. C. an 
crushing larger particles with flattened glass rod. Filter through a tare 
Gooch crucible with asbestos mat, wash free from alkali with distilled 
water, and dry at 100.degree. C. to constant weight. The increase in 
weight represents alkali-insoluble matter. 
##STR3## 
.sup.d The total chlorinated phenols are determined in the following way: 
The total chlorinated phenol content is determined by titration of dry 
pentachlorophenol with sodium hydroxide. 
Reagents - 
(a) CO.sub.2 -free 95 percent ethyl alcohol. 
Note: 
Ethyl alcohol denatured according to formula 2B of the appendix to 
Regulations No. 3, Formulae for Completely and Specially Denatured Alcoho 
is suitable for this purpose. Distill the ethyl alcohol (formula 2B) over 
caustic pellets. Store in a stoppered bottle. 
(b) Meta cresol purple indicator solution. Place 0.100 grams of meta 
cresol purple in a small mortar, add 2.62 milliliters of N/10 aqueous 
NaOH. Rub with the pestle until solution is complete. Transfer the 
solution to a 100-milliliter volumetric flask and make up to volume with 
distilled water. 
Procedure 
Weigh a 1.0000-gram sample and transfer to a clean 250-milliliter 
Erlenmeyer flask. Add 65 milliliters of ethyl alcohol and gently swirl 
until solution of the sample is complete. Add 35 milliliters of distilled 
water and subtract from above titration. 
Net ml. of N/10 NaOH .times. 0.02663 .times. 100 = Total chlorinated 
phenols as percent pentachlorophenol. 
Note: 
Ethyl alcohol solutions pick up CO.sub.2 from the air fairly rapidly, 
therefore, titrate sample immediately after dissolving in the alcohol. 
.sup.e The hexane test consists of dissolving 2.5 grams of the 
pentachlorophenol in 2.5 ml of methanol (with warming) and then adding th 
solution with stirring to 50 mls of hexane. The solubility test passed if 
no precipitate forms in 20 minutes. 
EXAMPLE VII 
In this experiment, pentachlorophenol was prepared in the manner described 
in Example VI, but in this case, the presence of chlorinated dibenzofurans 
were checked analytically by use of mass spectrometry methods in both the 
test and control batches. Heptachlorodibenzofuran (isomers not identified) 
was reduced 20-40% and 1,2,3,4,5,6,7,8-octachlorodibenzofuran was reduced 
70-94% when diphenyl sulfide was employed with aluminum chloride as the 
catalyst system as compared with the control tests. 
TABLE III 
__________________________________________________________________________ 
SHOWING REDUCED CHLORINATED DIOXINS USING DIPHENYL 
SULFIDE AS INHIBITOR AGENT IN MANUFACTURE OF 
PENTACHLOROPHENOL 
AMOUNTS OF CHLORINATED 
DIOXINS EXPRESSED IN 
FORM OF TS PER MILLION 
PENTACHLORO- TOTAL 
PHENOL AMOUNT HEXA- HEPTA- 
OCTO- CHLORO- 
BATCH 
MANU- OF DPS* CHLORO- 
CHLORO- 
CHLORO- 
INATED 
NO. FACTURE ADDED (LBS) 
DIOXINS 
DIOXINS 
DIOXINS 
DIOXINS 
__________________________________________________________________________ 
34-2-1275 
mold 0.125 89 458 2491 3039 
46-2-275 
mold 0.250 36 233 1215 1485 
47-2-1275 
mold 0.750 39 233 1542 1815 
44-2-1275 
mold 2.000 34 311 178 523 
45-2-1275 
mold 8.000 58 183 877 1118 
16-2-1275 
mold 0.000 (controls) 
258 938 2747 3944 
18-2-1275 
mold 0.000 (2nd control) 
200 763 3008 3972 
19-2-1275 
mold 0.000 (3rd control) 
196 890 3582 4668 
29-2-1275 
shotted 0.500 45 417 2180 2641 
36-2-1275 
shotted 0.750 47 329 2223 2629 
10-2-1275 
shotted 1.250 29 454 1868 2350 
24-2-1275 
shotted 4.000 18 210 1323 1551 
26-2-1275 
shotted 0.000 (control) 
154 670 2884 3709 
13-2-1275 
shotted 0.000 (2nd control) 
115 567 2428 3111 
__________________________________________________________________________ 
*Diphenyl sulfide