Process for preparation of resorcinol

A process for the preparation of resorcinol from diisopropylbenzene includes the steps of oxidizing m-diisopropylbenzene under anhydrous, non-alkaline conditions with oxygen, extracting m-diisopropylbenzene dihydroperoxide and m-diisopropylbenzene hydroxyhydroperoxide with dilute sodium hydroxide, re-extracting with an organic solvent, converting m-diisopropylbenzene hydroxyhydroperoxide to m-diisopropylbenzene dihydroperoxide with hydrogen peroxide, drying the product, decomposing the m-diisopropylbenzene dihydroperoxide in the presence of a catalyst selected from the group consisting of boron trifluoride, ferric chloride and stannic chloride to coproduce resorcinol and actone, and purifying the resorcinol.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to processes for the preparation of 
resorcinol, and more particularly to the preparation of resorcinol by 
hydroperoxidation of diisopropylbenzene. 
2. Description of the Prior Art 
Resorcinol, or 1,3-benzenediol, has numerous industrial applications, such 
as its use in the manufacture of fluorescein, eosin, and other dyes, 
synthetic drugs, and photographic developers or its use as a reagent, 
reducing agent, external dehydrant, antiseptic, antiferment and 
bactericide. A well known method of preparing resorcinol has been via a 
sulfonation-fusion process. Another known method is via the cyclization of 
methyl 4-oxocaproate from methyl acrylate and acetone followed by 
dehydrogenation. 
In 1972, researchers at the Stanford Research Institute reviewed a new 
route for the preparation of resorcinol via hydroperoxidation. The 
Stanford process involves production of a m-diisopropylbenzene (m-DIPB) by 
alkylation of benzene and/or cumene with propylene, followed by oxidation 
of the m-DIPB to the diisopropylbenzene dihydroperoxide (DHP). The DHP is 
decomposed with the aid of an acid catalyst to form resorcinol and 
acetone. 
Numerous patents have since issued which pertain to the preparation of 
resorcinol by hydroperoxidation. 
One commercial process, believed to be practiced by the Sumitomo Chemical 
Company, Ltd. is described in part by Suda et al. U.S. Pat. No. 3,953,521, 
British Patent Specification No. 921,557, Suda et al. U.S. Pat. No. 
3,950,431, Suda et al. U.S. Pat. No. 3,923,908, Suda et al. U.S. Pat. No. 
3,928,469, and Japanese Pat. No. 61-327 and Japanese Kokai No. 58-88357. 
The Sumitomo process involves the continuous production of m- and p-DHP by 
hydroperoxidation of m- and p-DIPB in liquid phase using an alkali 
catalyst, such as 10-20 vol % of a 2% sodium hydroxide (NaOH) solution at 
95.degree.-115.degree. C. and air at a pressure within the range of 
atmospheric to 10 atmospheres. The hydroperoxidation product is extracted 
with a 4% aqueous sodium hydroxide solution to separate DHP and 
m-diisopropylbenzene hydroxyhydroperoxide (HHP) from unreacted m-DIPB and 
diisopropylbenzene monohydroperoxide (MHP). The MHP/m-DIPB fraction is 
recycled to the hydroperoxidation reaction vessel. The DHP/HHP fraction, 
in the form of an aqueous solution containing sodium salts of DHP and HHP, 
is heated to 80.degree. C. and extracted with methyl isobutyl ketone 
(MIBK) to recover DHP and HHP. The MIBK solution of DHP/HHP is then washed 
with an organic solvent to reduce the HHP content, and mixed with an acid 
catalyst, such as 0.5-2% concentrated sulfuric acid (H.sub.2 SO.sub.4) 
and, in some instances, hydrogen peroxide (H.sub.2 O.sub.2) to decompose 
the DHP to either resorcinol or hydroquinone and acetone. The 
decomposition product is then neutralized with an aqueous ammonia 
solution, then distilled to obtain crude resorcinol or hydroquinone. 
Methods for purifying the crude resorcinol are described in Suda et al. 
U.S. Pat. Nos. 3,929,920; 3,911,030, and 3,969,420, and Japan Kokai No. 
78-53626 and British Pat. No. 2,061,926 A. 
Another commercial process, believed to be practiced by Mitsui 
Petrochemical Industries, is described in Nambu et al. U.S. Pat. No. 
4,237,319, Imai et al. U.S. Pat. No. 4,267,387, Nakagawa et al. U.S. Pat. 
No. 4,283,570, Imai et al. U.S. Pat. No. 4,339,615, and Japan Kokai Nos. 
61-180764 and 59-212440. The Mitsui process involves the hydroperoxidation 
of m-DIPB with molecular oxygen under aqueous alkaline conditions, for 
example, in the presence of 2% sodium hydroxide at 80.degree. 
C.-110.degree. C. for a period sufficient to react at least 90% of the 
DIPB. The hydroperoxidation product is dissolved in toluene and the 
aqueous sodium hydroxide solution is recycled to the hydroperoxidation 
reaction vessel for further use. The toluene solution is treated with 
excess hydrogen peroxide in the presence of small amounts of sulfuric acid 
to convert HHP and m-diisopropylbenzene dicarbinol (DCL) to DHP. The 
by-product water is azeotropically continuously removed. The toluene 
solution of DHP is then decomposed to resorcinol and acetone with 
concentrated sulfuric acid in substantial absence of hydrogen peroxide. 
The decomposition product is washed with aqueous sodium sulfate (Na.sub.2 
SO.sub.4) and distilled to obtain crude resorcinol. 
A process for recovery of the resorcinol from the acetone/resorcinol, 
mixture is described in Hashimoto et al. U.S. Pat. No. 4,273,623. The 
acid-decomposition reaction mixture is subjected to distillation to 
separate the resorcin containing concentrate from the acetone, wherein 
water is added to the decomposition reaction mixture in 20-70% by weight 
based on the weight of the resorcinol prior to distillation. Additional 
methods of purifying the crude resorcinol are described in Hashimoto et 
al. U.S. Pat. No. 4,239,921 and Canadian Pat. No. 1,115,733. 
The commercial processes described above each include a peroxidation step 
employing oxygen or air and aqueous sodium hydroxide for converting DIPB 
to DHP and other by-products, an extraction step for separating DHP from 
the peroxidation by-products, an acid cleavage step employing sulfuric 
acid for decomposing DHP to either resorcinol or hydroquinone and acetone, 
a neutralization step and a distillation step to purify the crude 
resorcinol or hydroquinone. 
The extraction step in the Sumitomo process includes a caustic extraction 
with 4% sodium hydroxide followed by organic extraction with MIBK. The 
Sumitomo process employs hydrogen peroxide in addition to the sulfuric 
acid in the acid cleavage step. The extraction step in the Mitsui process 
involves only organic extraction with toluene and is followed by oxidation 
with hydrogen peroxide and removal of water. 
It is believed that neutralization in the Sumitomo process is by means of 
aqueous ammonia and removal of aqueous ammonium hydrogen sulfate 
((NH.sub.4)HSO.sub.4). It is also believed that neutralization in the 
Mitsui process is by means of aqueous sodium sulfate and subsequent 
removal of aqueous sodium hydrogen sulfate (NaHSO.sub.4). The organic 
solvents in each process, MIBK and toluene, respectively, are removed in 
the distillation step and recycled for use in the organic extraction step. 
The hydroperoxidation of DIPB produces a variety of by-products in addition 
to the desired DHP. Isolation of DHP from the oxidation products without 
causing its decomposition has been the object of several patent 
disclosures. British Patent Application GB NO. 2 071 662 A discloses the 
use of superacids such as boron trifluoride in the preparation of 
resorcinol from m-DIPB. British Pat. No. 921,557, referenced above, 
disclosed the principle that DHP can be extracted from aqueous alkaline 
solutions in a much more favorable manner at higher temperatures (e.g. 
80.degree. C.) than ambient temperature. The direct extraction method, 
however, has a very serious problem; that is, the decomposition of DHP to 
HHP (and to a lesser degree to DCL) during the alkaline extraction 
process. Sumitomo Chemical Company, Ltd. owns several patents dealing with 
a method for extracting DHP. One Sumitomo process described in Canadian 
Pat. No. 1,056,407, discloses extracting DHP by a counter current 
multistage extraction with a temperature gradient between each stage and 
with all of the extractions being made at a temperature from 0.degree. to 
85.degree. C. and the aqueous alkali solution being fed to the lower 
temperature zone. Another Sumitomo patent, U.S. Pat. No. 3,932,528, 
disclosed that in order to prevent the DHP loss during the alkaline 
extraction, 0.01 to 1 wt % of ammonia or aromatic amine (based on the 
weight of the solution) is added to the aqueous alkaline solution. 
An object of the present invention is to improve the yield of resorcinol in 
a commercial process. A further object of the invention is to improve the 
selectivity to DHP in the hydroperoxidation step. 
SUMMARY OF THE INVENTION 
The objects of the present invention are satisfied by a new process for the 
preparation of resorcinol by the hydroperoxidation route. Generally, the 
process of the present invention proceeds as follows. An m-DIPB rich feed 
stream is hydroperoxidized using a new anhydrous, non-alkaline process. 
The hydroperoxidation product is extracted with dilute sodium hydroxide to 
separate m-DHP and m-HHP from unreacted m-DIPB and the other 
hydroperoxidation products. The m-DHP/m-HHP product is re-extracted from 
the sodium hydroxide solution with an organic solvent, preferably MIBK, 
and preferably then oxidized with a hydrogen peroxide solution to obtain 
pure m-DHP. The m-DHP is then decomposed in the presence of a minute 
quantity of a catalyst selected from the group consisting of a boron 
trifluoride and stannic chloride, to coproduce resorcinol and acetone. The 
yield of resorcinol from the DHP/HHP hydroperoxidation product is between 
85 and 90%. The overall molar yield of resorcinol is 80 to 86% from m-DIPB 
.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
In the process of the present invention, shown schematically in the Figure, 
a feed stream, comprised of major amounts of m-DIPB and less than about 6% 
o-DIPB is oxidized with oxygen or air in a nonaqueous, non-alkaline system 
at about 85.degree. C.-95.degree. C. The hydroperoxidation product is 
extracted with dilute aqueous sodium hydroxide to separate the DHP/HHP 
fraction as in the Sumitomo process. About 80% of the remaining 
hydroperoxidation products, including the MHP/unreacted DIPB fraction is 
recycled to the feed stream for further hydroperoxidation. The aqueous 
sodium hydroxide solution is extracted back with hot MIBK to recover the 
DHP/HHP product. The MIBK is evaporated. The DHP/HHP product is then 
preferably dissolved in toluene and treated with hydrogen peroxide in the 
presence of a small amount of sulfuric acid to convert most of the HHP to 
DHP without decomposing DHP. Finally the DHP is decomposed to resorcinol 
and acetone using a new catalyst, preferably boron triflouride 
(BF.sub.3)-etherate. The catalyst is very effective and only a minute 
amount is required. Alternatively, stannic chloride or ferric chloride may 
be used as the catalyst in the decomposition step. The decomposition 
product is purified by any suitable means, such as washing with dilute 
sodium hydroxide and distilling to obtain resorcinol. 
There are three unique steps in the hydroperoxidation process of the 
present invention. They are (1) hydroperoxidation of m-DIPB to m-DHP, (2) 
oxidation of by-product m-HHP to m-DHP with hydrogen peroxide (H.sub.2 
O.sub.2), and (3) decomposition of m-DHP to resorcinol and acetone. 
The remaining steps include: (1) the preparation of m-DIPB by the 
Friedel-Crafts alkylation of benzene with propylene; (2) extraction of the 
m-DHP/m-HHP fraction from the hydroperoxidation mixture with dilute sodium 
hydroxide; and (3) separation and purification of resorcinol by known 
techniques. 
Peroxidation Of m-DIPB 
In prior art hydroperoxidation processes, DIPB is oxidized in a pressurized 
reactor with either air or molecular oxygen in the presence of sufficient 
dilute aqueous sodium hydroxide to maintain the pH between 7 and 9. In the 
present invention, the oxidation of DIPB with oxygen is carried out 
without using dilute aqueous sodium hydroxide. 
In the prior art hydroperoxidation processes, m-DIPB is reacted with oxygen 
in the liquid phase at 80.degree. to 130.degree. C. In commercial scale 
processes the reaction is run at temperatures in the upper portion of the 
range, 95.degree. to 100.degree. C. The higher temperatures in turn 
require higher pressure to prevent evaporation. Here m-DIPB is oxidized 
first to monohydroperoxide (MHP) which in turn is oxidized to 
dihydroperoxide (DHP). Since both MHP and DHP are thermally unstable under 
the peroxidation conditions, at higher temperatures many other products 
are also formed. In the initial stages of the oxidation, MHP is the main 
product because the concentration of DIPB is much greater than MHP. While 
being oxidized to DHP, MHP can also give up one oxygen atom to form a 
monocarbinol (MCL, isopropylphenyldimethyl carbinol) which in turn can be 
oxidized to hydroxyhydroperoxide (HHP), as follows: 
##STR1## 
At the same time, smaller amounts of the corresponding monoketone (MKT) 
and ketone hydroperoxide (KHP) are formed, by splitting off methanol from 
MHP and DHP, respectively. The KHP can lose another molecule of methanol 
to form a diketone (DKT, 1,3-diacetylbenzene). 
##STR2## 
At the temperature employed in the prior art systems for the oxidation of 
DIPB (80.degree.-130.degree. C.), the ratio of ketone formation to 
carbinol formation is roughly 1 to 3. Finally, the HHP may lose an oxygen 
atom to form a dicarbinol (DCL). All the products mentioned above have 
been found in the oxidation product of m-DIPB. However, the three products 
present in the largest amount are MCL, DCL and diisopropylbenzene olefin 
carbinol (OLCL), which are formed by dehydration of DCL. 
##STR3## 
EXAMPLE I 
Hydroperoxidation Under Anhydrous, Non-Alkaline Conditions 
Table I shows the analysis of products from the hydroperoxidation of CP 
grade m-DIPB in a nonaqueous, non-alkaline medium. 
Hydroperoxidation was made in a one-liter 3-neck flask equipped with a 
stirrer, thermometer, reflux condenser, and gas-bubbler. The reaction 
mixture in the flask was stirred and heated to the desired temperature 
with a heating mantle while approximately 100 ml/min. oxygen was bubbled 
through the reaction mixture. 
In the initial hydroperoxidation, when no recycle m-MHP/m-DIPB was used, 
700 g CP grade m-DIPB and 30 g initiator, which was a 51% m-MHP/m-DIPB 
mixture, were used as the starting material. In the subsequent recycle 
experiments (Recycle Runs 1 to 9), the recycle m-MHP/m-DIPB fraction 
(usually about 650 g) was mixed with enough fresh m-DIPB to make 750 g of 
starting material. 
During the hydroperoxidation, a small sample (0.5 g) was removed from the 
reaction mixture every four hours and titrated iodometrically to determine 
total peroxide concentraiton expressed as % MHP. 
##EQU1## 
Hydroperoxidation was terminated when the titrated % MHP value reached 
about 75%-80%, which normally took about 16 to 24 hours. 
The DHP/HHP product was obtained by extracting the hydroperoxidation 
product with dilute aqueous alkaline solution. The remaining organic 
phase, which contained about a 2:1 ratio of MHP/DIPB, was recycled. In the 
cyclic hydroperoxidation, the recycle MHP/DIPB was mixed with fresh DIPB 
equivalent to the amount of DHP/HHP product removed in order to maintain 
the same moles of MHP and DIPB throughout the cyclic process. In the 
actual operation, a constant weight of hydroperoxidation feed was charged 
in all 9 cycles of hydroperoxidation to meet this requirement. 
TABLE I 
__________________________________________________________________________ 
DHP/HHP from CP m-DIPB, 100% Recycle 
MHP/DIPB 
Conditions DHP/HHP 
Recycle 
DIPB Net Production.sup.2 
Recycle 
time 
temp. 
MHP,.sup.1 
wt, 
DHP,.sup.1 
wt, 
MHP,.sup.1 
Conv..sup.2,3 
DHP HHP DHP/DHP + HHP 
No. hrs 
.degree.C. 
% g % g % % Mol % 
Mol % 
% 
__________________________________________________________________________ 
0 32 82-88 
73.3 
161.0 
89.5 
674 
54.9 
66.3 14.8 
1.7 89.7 
1 16 84-85 
75.4 
100.3 
85.5 
685 
59.7 
43.5 -- -- -- 
2 16 83-85 
75.9 
96.5 
83.6 
661 
61.6 
-- 9.0 2.7 76.9 
3 16 84-85 
77.9 
126.4 
87.8 
648 
62.2 
41.7 12.5 
2.2 85.0 
4 24 85 86.2 
183.0 
86.1 
613 
56.6 
53.4 17.2 
2.2 88.7 
5 24 85-86 
76.5 
84.3 
88.2 
663 
62.9 
48.8 8.0 2.6 75.5 
6 24 85-90 
77.7 
128.0 
84.7 
651 
56.1 
43.6 9.9 2.7 78.6 
7 24 83-87 
73.5 
79.5 
82.2 
690 
61.6 
40.8 7.9 2.5 76.0 
8 24 85-91 
75.7 
83.8 
81.0 
697 
63.7 
35.1 7.4 3.8 66.1 
9 24 87-93 
71.6 
77.0 
73.6 
708 
59.4 
32.6 4.6 4.2 52.2 
Av. 1-9 76.7 
106.5 
83.6 
668 
60.4 
42.4 8.5 2.5 77.0 
__________________________________________________________________________ 
.sup.1 By iodometric titration. 
.sup.2 Calculated from high performance liquid chromatographic analysis 
(HPLC). 
.sup.3 These conversions were calculated from data obtained under variabl 
caustic extraction conditions. 
Columns 3, 5 and 7 of Table I represent results of iodometric titration 
expressed as wt % MHP, DHP, and MHP, respectively. The iodometric 
titration determines the amount of active oxygen in the sample which is 
calculated as though it were a single hydroperoxide. It cannot be used to 
distinguish different hydroperoxides. 
Data shown in columns 8, 9, and 10 of Table I were obtained by high 
performance liquid chromatographic (HPLC) analysis. They show the net 
conversion of DIPB and net production of DHP and HHP (as mol %) for each 
cycle of hydroperoxidation. The last line of Table I shows the average 
values for cycles 1 to 9. 
A quantitative determination of a mixture of hydroperoxides was made by 
HPLC analysis. Pure samples of DHP, MHP, DCL, OLCL, DKT, MCL, MKT, and HHP 
were used for the calibration of HPLC data. The results are shown in Table 
II. 
TABLE II 
__________________________________________________________________________ 
Composition of Product From Hydroperoxidation of CP m-DIPB 
COMPONENTS, Mol % 
DCL 
OLCL 
DKT HHP 
DHP 
MCL MHP MKT DIPB 
__________________________________________________________________________ 
Recycle 0 
Product 
0.4 
0.3 &lt;0.1 
1.7 
14.8 
8.2 40.0 
1.1 33.7 
Net Prodn. 
0.4 
0.3 &lt;0.1 
1.7 
14.8 
8.2 40.0 
1.1 -66.3 
Recycle 1 
and 2 
Product 
0.4 
0.5 &lt;0.1 
2.7 
9.0 
9.8 48.1 
1.5 27.9 
Charge 0.3 
0.2 0 0.5 
1.4 
7.8 39.3 
1.1 49.4 
Net Prodn. 
0.1 
0.3 &lt;0.1 
2.2 
7.6 
2.0 8.8 0.4 -21.5 
Recycle 3 
Product 
0.6 
0.7 &lt;0.1 
3.0 
13.6 
10.2 
45.6 
1.6 24.6 
Charge 0.3 
0.4 0 0.8 
1.1 
9.1 44.7 
1.4 42.2 
Net Prodn. 
0.3 
0.3 &lt;0.1 
2.2 
12.5 
1.1 0.9 0.2 -17.6 
Recycle 4 
Product 
0.7 
0.8 &lt;0.1 
3.5 
19.7 
9.9 42.3 
1.6 21.5 
Charge 0.5 
0.6 0 1.3 
2.5 
8.7 39.0 
1.5 46.1 
Net Prodn. 
0.2 
0.2 &lt;0.1 
2.2 
17.2 
1.2 3.3 0.1 -24.6 
Recycle 5 
Product 
0.9 
2.0 &lt;0.1 
3.9 
10.6 
13.3 
45.1 
1.3 22.9 
Charge 0.6 
0.7 0 1.3 
2.6 
9.0 39.6 
1.5 44.7 
Net Prodn. 
0.3 
1.3 0.1 2.6 
8.0 
4.3 5.5 -0.2 
-21.8 
Recycle 6 
Product 
1.1 
2.0 &lt;0.1 
4.2 
10.6 
12.7 
41.0 
1.1 27.2 
Charge 0.7 
1.2 0 1.5 
0.7 
10.1 
36.7 
0.9 48.2 
Net Prodn. 
0.4 
0.8 &lt;0.1 
2.7 
9.9 
2.6 4.3 0.2 -21.0 
Recycle 7 
Product 
1.1 
2.3 &lt;0.1 
4.8 
10.6 
12.1 
43.2 
1.5 24.4 
Charge 1.0 
2.1 0.02 
2.3 
2.7 
11.8 
37.7 
1.2 41.2 
Net Prodn. 
0.1 
0.2 &lt;0.08 
2.5 
7.9 
0.3 5.5 0.3 -16.8 
Recycle 8 
Product 
1.8 
3.5 0.05 
7.3 
11.0 
12.3 
40.3 
1.6 22.2 
Charge 0.9 
2.8 0 3.5 
3.6 
11.8 
42.8 
1.5 34.2 
Net Prodn. 
0.9 
0.7 0.05 
3.8 
7.4 
0.5 -2.5 
0.1 -12.0 
Recycle 9 
Product 
2.7 
5.1 0.1 9.5 
8.8 
13.6 
35.5 
1.9 23.0 
Charge 1.5 
3.1 0 5.3 
4.2 
11.8 
38.5 
1.6 34.1 
Net Prodn. 
1.2 
2.0 0.1 4.2 
4.6 
1.8 -3.0 
0.3 -11.1 
Recycle 1-9 
Tot. Prodn. 
3.5 
5.8 0.7 22.4 
75.1 
13.8 
22.8 
1.4 -146.4 
__________________________________________________________________________ 
Referring again to Example 1 and Table I, after 10 hydroperoxidation 
cycles, a total of 1120 g DHP/HHP product was obtained. From the HPLC 
data, it was calculated that for the nine cyclic operations the average 
mol % DHP in DHP+HHP product stream was 77%, excluding a small fraction of 
MHP which was also extracted into the product stream and should be removed 
from the product stream. It was also found that the average DIPB 
conversion was 42.4%. The ratio of product (DHP+HHP) v. recycle (MHP+DIPB) 
was 106.5:668-1:6.3 for the nine recycles. These values are low compared 
to those obtained in subsequent experiments using commercial m-DIPB. Based 
on subsequent work, described in Table IX below, for a 50% DIPB 
conversion, a ratio of 1:4 can be expected. 
EXAMPLE 2 
Hydroperoxidation Under Aqueous, Alkaline Conditions 
In order to compare the results of Example 1 with aqueous, alkaline 
hydroperoxidation processes, four hydroperoxidation runs of CP m-DIPB in 
the presence of 2% aqueous sodium hydroxide solution were made using the 
same equipment. The results are shown in Table III. Since we did not use a 
pressure reactor, our experiments were limited to 1 atm and 100.degree. C. 
The present commercial processes are believed to use higher temperatures 
and higher pressure. 
The same one-liter flask was used for the hydroperoxidation of 600 g CP 
m-DIPB containing 30 g 56% m-MHP as initiator, in the presence of 65 g 2% 
aqueous sodium hydroxide. The subsequent hydroperoxidation with recycled 
MHP-DIPB was made with 650 g charge consisting of recycle MHP-DIPB and 
additional fresh m-DIPB. 
The reaction temperature was raised to 95.degree.-100.degree. C. because 
the hydroperoxidation was much slower than in nonaqueous, non-alkaline 
media. The use of greater than 1 atm and higher than 100.degree. C. was 
avoided in order to obtain data comparable with the data from nonaqueous 
hydroperoxidation. 
Generally the same work-up procedure as described above was used. After the 
hydroperoxidation experiment of Recycle 0, the aqueous layer was separated 
and the products from the experiments with equal weights of 10% aqueous 
sodium hydroxide. The products from the experiments of Recycles 1 and 2 
were extracted with equal weights of 4% aqueous sodium hydroxide. 
Extraction with 10% sodium hydroxide has produced a MHP/DIPB recycle that 
contains less DHP/HHP product. The composition of the hydroperoxidation 
products was calculated as before and shown in Table IV. 
TABLE III 
__________________________________________________________________________ 
DHP/HHP from CP m-DIPB in the Presence of Sodium Hydroxide 
MHP/DIPB 
Conditions DHP/HHP 
Recycle 
DIPB Net Production.sup.2 
Recycle 
time 
temp. 
MHP.sup.1 
wt DHP.sup.1 
wt MHP.sup.1 
Conv..sup.2 
DHP HHP DHP/DHP + HHP 
No. hrs. 
.degree.C. 
% g % g % % Mol % 
Mol % 
% 
__________________________________________________________________________ 
0 36 90-99 
58.0 
87.0 
79.7 
595 
43.8 
63.1 6.5 4.9 57.0 
1 28 95-100 
59.0 
93.6 
75.7 
542 
47.4 
45.4 5.9 6.5 47.6 
2 32 99 54.0 
83.9 
64.9 
569 
42.7 
44.3 3.2 6.4 33.3 
3 32 100 45.2 
56.6 
67.4 
453 
36.1 
35.6 3.2 3.0 51.6 
Av. 1-3 52.7 
78.0 
69.3 
521 
42.1 
41.8 4.10 
5.30 
43.6 
__________________________________________________________________________ 
.sup.1 By iodometric titration. 
.sup.2 Calculated from HPLC analysis. 
TABLE IV 
__________________________________________________________________________ 
Hydroperoxidation Products From CP m-DIPB in the Presence of 2% NaOH 
COMPONENTS, Mol % 
DCL OLCL 
DKT HHP 
DHP 
MCL MHP MKT DIPB 
__________________________________________________________________________ 
Recycle 0 
Product 
0.6 
2.0 &lt;0.1 
4.9 
6.5 
11.9 
36.2 
1.0 36.9 
Net Prodn. 
0.6 
2.0 &lt;0.1 
4.9 
6.5 
11.9 
36.2 
1.0 -63.1 
Recycle 1 
Product 
1.7 
4.7 &lt;0.1 
8.0 
6.7 
15.8 
33.8 
2.0 27.3 
Charge 
0.5 
1.7 0 1.5 
0.8 
11.0 
33.5 
1.0 50.0 
Net Prodn. 
1.2 
3.0 &lt;0.1 
6.5 
5.9 
4.8 0.3 1.0 -22.7 
Recycle 2 
Product 
2.4 
8.6 &lt;0.1 
9.6 
3.7 
18.3 
28.7 
2.9 25.7 
Charge 
1.2 
3.9 0 3.2 
0.5 
13.9 
29.4 
1.7 46.1 
Net Prodn. 
1.2 
4.7 &lt;0.1 
6.4 
3.2 
4.4 -0.7 
1.2 -20.4 
Recycle 3 
Product 
4.0 
10.8 
&lt;0.1 
6.7 
3.7 
23.3 
25.1 
3.5 22.8 
Charge 
1.9 
7.5 0 3.5 
0.7 
17.9 
30.2 
2.9 35.4 
Net Prodn. 
2.1 
3.3 &lt; 0.1 
3.2 
3.0 
5.4 -5.1 
0.6 -12.6 
__________________________________________________________________________ 
Comparing the data of Tables I and III, it is apparent that the 
hydroperoxidation of m-DIPB in an anhydrous, non-alkaline media is better 
in many aspects than hydroperoxidation in the presence of dilute aqueous 
sodium hydroxide. First, the average final hydroperoxide concentration, 
calculated as wt % MHP from iodometric titrations was 76.7% for the nine 
cycles of nonaqueous hydroperoxidation, whereas the corresponding value 
for the three cycles in the presence of 2% aqueous sodium hydroxide was 
52.7%. Second, the average % DHP of the DHP/HHP fraction, determined by 
iodometric titration, was 83.6% for the former and 69.3% for the latter. 
The value of DHP/DHP+HHP was 77.0% and 43.6%, respectively. It is 
concluded that hydroperoxidation in nonaqueous, non-alkaline media gives 
higher conversion of m-DIPB and better selectivity to the desired product. 
Comparing the hydroperoxidation of Recycle 0 (pure DIPB oxidation), the 
caustic extraction produces 87.0 g DHP/HHP fraction v. 161.0 g for the 
nonaqueous system. For the first three recycles, the average DHP/HHP 
product weighed 78.0 g v. 107.7 g for the nonaqueous system. In the 
oxidation process, the addition of water slows the process. It appears 
that the hydroperoxidation of m-DIPB in the presence of aqueous sodium 
hydroxide does in fact take place at a much slower rate than the 
hydroperoxidation in nonaqueous media. 
Since hydroperoxidation of DIPB in the presence of aqueous sodium hydroxide 
is a slower reaction compared to that of the nonaqueous system, it would 
be expected to produce a lower quality DHP/HHP fraction. This, indeed, was 
observed. The average selectivity of DHP/HHP product from the aqueous 
sodium hydroxide runs was 43.6 mol % compared to 77.0 mol % for the 
nonaqueous system. 
A possible, although somewhat over-simplified explanation of the results 
can be made as follows: 
In the hydroperoxidation of DIPB to DHP, most of the DHP is produced in the 
chain propagation step of 
##STR4## 
On the other hand, some HHP is produced from decomposition of DHP, e.g., 
##STR5## 
In the fast oxidation of DIPB, the chain propagation takes place rapidly 
and the production of DHP is favored. Only when the oxidation is slowed 
down, the decomposition of DHP becomes competitive, resulting in the 
production of more HHP. 
As the concentration of HHP in the hydroperoxidation mixture increase, it 
can decompose to form secondary products, such as DCL and OLCL. 
In order to compensate for the slower hydroperoxidation, commercial prior 
art processes employ higher reaction temperature and pressure, which in 
turn produce more by-products. 
The nonaqueous hydroperoxidation process of the present invention permits 
operation at a lower reaction temperature, ideally about 85.degree. C., 
and at a lower pressure, to achieve a high product selectivity. The 
oxidation process of the present invention can therefore be run in an open 
system without concern for pressure reaction vessels. 
The process of the present invention produces its best results when the 
DIPB in the feed stream is comprised of major amounts of m-DIPB and less 
than about 6% o-DIPB. Commercially available DIPB, manufactured by 
alkylating benzene with propylene, usually contains all three isomers (o, 
m, and p). Since it is difficult to separate o-DIPB from m-DIPB by 
fractional distillation, it is important to determine the amount of the 
o-isomer tolerable in the DIPB feed. 
Synthetic feeds of m-DIPB containing 2.5% and 5% o-DIPB were prepared and 
used in the cyclic hydroperoxidation study. Tables V and VI show the 
results of those experiments. 
EXAMPLE 3 
Hydroperoxidation of m-DIPB Containing 2.5% o-DIPB 
Hydroperoxidation of 750 g m-DIPB containing 2.5% o-DIPB was made in a 
one-liter flask at 85.degree.-88.degree. C. and 1 atm in nonaqueous, 
non-alkaline media using the same procedure as described earlier. In all 
experiments products were extracted once with an equal weight of 4% 
aqueous sodium hydroxide to separate the DHP/HHP fraction. The aqueous 
sodium hydroxide solution was extracted once with twice its weight and 
once with an equal weight of MIBK at 80.degree. C. to recover the DHP/HHP 
fraction. Again, both the product and the recycle MHP/DIPB were analyzed 
by HPLC to determine their composition. 
EXAMPLE 4 
Hydroperoxidation of m-DIPB Containing 5% o-DIPB 
Hydroperoxidation of 350 g m-DIPB containing 5% o-DIPB was made in a 500-ml 
flask at 85.degree.-92.degree. C. and 1 atm in nonaqueous, non-alkaline 
media for a period of about 24 hours, until the peroxide concentration was 
about 50-70% MHP. The product was extracted once with an equal weight of 
4% aqueous sodium hydroxide. The aqueous sodium hydroxide solution 
containing the sodium salts of DHP and HHP was extracted twice at 
80.degree. C. with twice its volume of MIBK to isolate the DHP/HHP 
product. After evaporation of MIBK, the residue was analyzed by HPLC to 
determine its DHP/HHP content. 
TABLE V 
__________________________________________________________________________ 
DHP/HHP from m-DIPB Containing 2.5% o-DIPB, 100% Recycle 
MHP/DIPB 
Conditions DHP/HHP 
Recycle 
DIPB Net Production.sup.2 
Recycle 
time 
temp. 
MHP.sup.1 
wt DHP.sup.1 
wt MHP.sup.1 
Conv..sup.2 
DHP HHP DHP/DHP + HHP 
No. hrs. 
.degree.C. 
% g % g % % Mol % 
Mol % 
% 
__________________________________________________________________________ 
0 32 85-89 
71.3 
98.0 
83.0 
712 
61.3 
62.2 11.7 
2.0 85.4 
1 16 85-87 
77.3 
85.7 
86.9 
686 
64.0 
31.5 7.7 2.1 78.6 
2 16 85-87 
72.5 
86.0 
82.4 
660 
64.1 
25.6 6.3 1.7 78.7 
3 24 85-87 
74.7 
82.5 
79.9 
668 
62.8 
38.0 6.9 3.0 69.7 
4 24 87-88 
72.4 
79.0 
79.6 
678 
63.5 
32.1 6.5 2.6 71.4 
5 24 87 71.6 
80.0 
76.8 
650 
60.2 
34.1 6.1 3.4 64.2 
6 24 85-88 
63.1 
69.1 
70.9 
677 
55.6 
29.8 4.1 2.2 65.1 
7 24 86-87 
58.9 
67.2 
67.3 
658 
50.9 
30.8 3.4 2.5 57.6 
8 24 87-89 
55.2 
62.4 
64.7 
666 
47.4 
35.8 3.4 2.4 58.6 
9 24 87-88 
53.5 
61.2 
63.7 
673 
N.D..sup.3 
47.7 2.8 4.1 40.6 
10 24, 
87-88 
55.0 
59.8 
63.1 
664 
44.9 
46.9 2.7 2.3 54.0 
Av. 1-10 65.4 
73.3 
73.5 
668 
57.0 
35.2 4.99 
2.63 
65.5 
__________________________________________________________________________ 
.sup.1 By iodometric titration. 
.sup.2 Calculated from HPLC analysis. 
.sup.3 Not determined. 
TABLE VI 
__________________________________________________________________________ 
DHP/HHP from m-DIPB Containing 5.0% o-DIPB, 100% Recycle 
MHP/DIPB 
Conditions DHP/HHP 
Recycle 
DIPB Net Production.sup.2 
Recycle 
time 
temp. 
MHP wt DHP.sup.1 
wt MHP.sup.1 
Conv..sup.2 
DHP HHP DHP/DHP + HHP 
No. hrs. 
.degree.C. 
% g % g % % Mol % 
Mol % 
% 
__________________________________________________________________________ 
0 40 80-96 
75.4 
47.6 
80.7 
305 
60.3 
67.0 11.2 
7.8 59.0 
1 24 85-91 
64.3 
30.5 
80.0 
338 
59.9 
37.8 5.4 3.7 59.3 
2 24 85-92 
71.7 
40.6 
74.1 
269 
61.2 
43.6 6.1 3.8 61.6 
3 24 88-92 
59.4 
32.8 
68.8 
273 
51.5 
38.9 3.5 2.9 54.7 
4 24 87-90 
53.4 
34.1 
62.7 
269 
43.9 
41.3 3.1 1.1 73.8 
5 32 86-90 
52.9 
32.4 
63.9 
276 
43.2 
43.0 3.3 2.4 57.9 
Av. 1-5 60.3 
34.1 
69.9 
285 
51.9 
40.9 4.28 
2.78 
60.6 
__________________________________________________________________________ 
.sup.1 By iodometric titration. 
.sup.2 Calculated from HPLC analysis. 
Comparison of the data in Table V and VI with the data in Table I shows 
that: 
(1.) Final hydroperoxide concentrations determined by iodometric titration 
are 10-15% higher in the cases of CP grade m-DIPB. 
(2.) The DHP/HHP fractions obtained by caustic extraction contain less DHP 
(% DHP by titration) in the experiments with m-DIPB containing 2.5% and 5% 
o-DIPB. The average % DHP by titration was 83.6% for CP grade m-DIPB, 
73.5% for m-DIPB containing 2.5% o-DIPB and 69.9% for m-DIPB containing 5% 
o-DIPB. 
(3.) The CP grade m-DIPB runs gave highest % DHP/DHP+HHP values (average 
77%) than the runs containing o-DIPB (65.5% and 60.6%, respectively). 
Analysis of the hydroperoxidation by-products revealed that the presence of 
o-dIPB in DIPB feed increases the production of by-products, such as OLCL 
and MKT. The average mol % OLCL and MKT in the hydroperoxidation products 
of CP DIPB were 0.61% and 0.25%, respectively. The corresponding values 
with DIPB containing 5% o-DIPB were 2.75% and 0.58%, respectively. 
It can be concluded, therefore, that a higher percentage of o-DIPB in the 
m-DIPB feed not only reduces the rates of m-DIPB hydroperoxidation, but 
also decreases the selectivity to the desirable products m-DHP and m-HHP. 
EXAMPLE 5 
Hydroperoxide of m-DIPB Containing Large Percentages of o-DIPB 
The same procedure was used to hydroperoxidate m-DIPB containing 10%, 26%, 
38%, and 43% o-DIPB, respectively, in the initial feed. The procedures 
were the same as those described for m-DIPB containing 5% o-DIPB, except 
that the percentage content of o-DIPB was altered accordingly. Technical 
grade DIPB containing 26% o-DIPB used in one experiment yielded recovered 
DIPB containing 38% o-DIPB which was used in another experiment. The 
recovered DIPB from the first recycle hydroperoxidation of the run 
containing 38% o-DIPB was found to contain 43% o-DIPB and was used as the 
charge for yet another experiment. 
Hydroperoxidation of m-DIPB containing 10% and 26% o-isomer failed to 
produce satisfactory yields of m-DHP, even after only one recycle. There 
was a significant increase in the production of undesirable by-products, 
including DCL, OLCL, and MKT. It took 64 hours (twice as long as standard 
experiments) to obtain a 41% m-DIPB conversion when m-DIPB containing 26% 
o-isomer was used. In a similar experiment using m-DIPB containing 38% 
o-isomer, the DIPB conversion was only 26% after 64 hours. It was not 
possible to carry out the hydroperoxidation of the MHP/DIPB recycles from 
these two experiments. There was no increase in hydroperoxide 
concentration when the MHP/DIPB recycle obtained from the 
hydroperoxidation of m-DIPB containing 38% o-DIPB was heated at 85.degree. 
C. in the presence of oxygen. The hydroperoxidation products from these 
two runs contained higher concentrations of by-products than the desirable 
DHP/HHP products, indicating a significant decomposition of DHP, HHP, and 
probably even MHP. 
From the data it has been determined that when the percentage of o-isomer 
in DIPB exceeds about 6%, hydroperoxidation of DIPB becomes increasingly 
difficult under the same experimental conditions. 
Additional experiments revealed that the hydroperoxidation of p-DIPB in 
nonaqueous, non-alkaline media behaved differently than the 
hydroperoxidation of m-DIPB. Hydroperoxidation of 100% p-DIPB under the 
conditions of the present invention showed no improvement over the yields 
of the prior art aqueous, alkaline hydroperoxidation processes. Moreover, 
and surprisingly, when the oxidation by-products, p-MHP/p-DIPB, were 
recycled to the feed stream for further hydroperoxidation, no 
hydroperoxides were produced under anhydrous, nonalkaline conditions. 
Because o-DIPB is not oxidized during the hydroperoxidation of m-DIPB, it 
accumulates in the unreacted DIPB stream and the concentration of o-DIPB 
increases with the number of recycles of the DIPB. 
It is generally recognized that it would be unrealistic to expect a 
commercial DIPB feed containing less than 1% o-isomer. Therefore, it is 
necessary to return a portion of the unreacted DIPB containing a higher 
percentage o-DIPB from the recycle stream and send it back to the 
alkylation plant for isomerization in order to prevent the build-up of 
o-DIPB which causes poor hydroperoxide yield. This can be done either by 
diverting a portion of recycle DIPB after each recycle or by displacing 
all unreacted DIPB after several recycles. 
EXAMPLE 6 
Hydroperoxidation of m-DIPB Containing 1.2% o-DIPB with an 80% Recycle of 
Recovered m-MHP and m-DIPB 
Hydroperoxidation of m-DIPB containing 1.2% o-DIPB was made using the same 
procedure as described above. The organic phase from the extraction with 
aqueous sodium hydroxide to remove DHP and HHP was washed with water, 
dried with 4A.degree. sieves, and flash distilled in a Rinco evaporator to 
remove approximately 20% of the unreacted DIPB from the recycle stream. 
The flash distillate was found to contain as much as 30% MHP and a smaller 
quantity of MCL by GLC analysis. 
The aqueous sodium hydroxide solution containing the sodium salts of DHP 
and HHP was extracted with MIBK to recover DHP and HHP fraction. 
Results are shown in Table VII. 
EXAMPLE 7 
Hydroperoxidation of m-DIPB Containing 1.2% o-DIPB, with a 100% Recycle 
Hydroperoxidation of each cycle was made with 350 g fresh DIPB feed and 
recycle MHP-DIPB mixture. After the hydroperoxidation, the product was 
extracted twice with equal weights of 4% aqueous sodium hydroxide to 
ensure a more complete extraction of m-DHP. The concentration of m-DHP in 
the recycle stream was determined to be less than 1%. The aqueous sodium 
hydroxide solution containing the sodium salts of m-DHP and m-HHP was 
extracted twice at 80.degree. C. with twice its volume of MIBK to extract 
back m-DHP and m-HHP. After evaporation of MIBK solvent, the product was 
analyzed by HPLC. 
Results are shown in Table VIII. 
EXAMPLE 8 
Hydroperoxidation of Commercial m-DIPB with an 80% Recycle of Recovered 
m-MHP and m-DIPB 
A 5-gallon sample of commercial m-DIPB was obtained and used without any 
treatment. Analysis of the commercial m-DIPB by GLC indicated a 98% purity 
of m-DIPB. Major impurities were: 0.8% o-DIPB, 0.4% p-DIPB, and less than 
0.2% trimethylindane. A technical data sheet supplied by the manufacturer 
showed: &gt;96% m-DIPB, 1.5% o-DIPB, and 0.5% p-DIPB. 
Hydroperoxidation was made with 350 g feed comprising of about 30 mol % 
fresh DIPB, 25 mol % recycle DIPB and 45-50 mol % recycle MHP, and smaller 
amounts of MCL, HHP and OLCL. The product was extracted twice with equal 
weights of (approximately 400 ml) 4% aqueous sodium hydroxide to remove 
DHP and HHP. The organic phase was washed with 100 ml water, dried with 35 
ml 4A.degree. sieves, and filtered. Samples of the MHP/DIPB recycle were 
analyzed by HPLC. 
The aqueous sodium hydroxide solution was extracted twice at 80.degree. C. 
with twice its volume of MIBK (800 ml each) to recover the DHP/HHP 
product. The MHP/DIPB recycle was flash distilled in a Rinco evaporator to 
remove about 20% of unreacted DIPB from each recycle. The results are 
shown in Table IX. 
TABLE VII 
__________________________________________________________________________ 
DHP/HHP From m-DIPB Containing 1.2% o-DIPB, 80% Recycle 
Conditions DHP/HHP MHP/DIPB Recycle 
DIPB 
Net Production.sup.2 
Recycle 
time 
temp. 
MHP.sup.1 
wt DHP.sup.1 
wt MHP.sup.1 
% o-in 
Conv..sup.2 
DHP HHP DHP/DHP + HHP 
No. hrs. 
.degree.C. 
% g % g % DIPB % Mol % 
Mol % 
% 
__________________________________________________________________________ 
0 40 87-89 
80.1 
76.4 
84.7 
281 61.1 
N.D..sup.3 
63.6 
14.0 4.0 77.8 
1 24 86-87 
78.0 
66.3 
80.8 
307 53.4 
N.D..sup.3 
50.1 
9.7 3.2 75.2 
2 24 86-87 
73.4 
64.4 
76.7 
308 56.7 
N.D..sup.3 
44.3 
9.6 3.2 75.0 
3 24 86-87 
78.8 
69.9 
81.9 
304 57.6 
N.D..sup.3 
50.3 
11.4 4.4 72.2 
4 24 86 60.5 
49.6 
62.7 
318 45.9 
N.D..sup.3 
42.6 
4.9 2.9 62.8 
5 24 85 54.4 
47.2 
68.7 
314 43.9 
N.D..sup.3 
30.1 
4.8 2.7 64.0 
6 24 85 63.0 
55.7 
75.5 
314 48.3 
N.D..sup.3 
44.9 
7.7 4.0 65.8 
7 24 85 69.9 
63.3 
76.9 
308 52.3 
N.D..sup.3 
46.8 
8.8 4.2 67.7 
8 24 85 76.3 
66.9 
82.1 
304 56.7 
N.D..sup.3 
46.4 
10.4 3.1 77.0 
9 24 85 75.1 
68.4 
80.7 
303 52.7 
N.D..sup.3 
47.2 
10.6 3.1 77.4 
10 24 85 78.1 
60.3 
83.0 
311 60.3 
4.5 41.7 
9.3 2.8 76.9 
Av. 1-10 70.8 
61.2 
76.9 
309 52.8 44.4 
8.72 3.36 
72.2 
__________________________________________________________________________ 
.sup.1 By iodometric titration. 
.sup.2 Calculated from HPLC analysis. 
.sup.3 Not determined. 
TABLE VIII 
__________________________________________________________________________ 
DHP/HHP From m-DIPB Containing 1.2% o-DIPB, 100% Recycle 
Conditions DHP/HHP MHP/DIPB Recycle 
DIPB 
Net Production.sup.2 
Recycle 
time 
temp. 
MHP.sup.1 
wt DHP.sup.1 
wt MHP.sup.1 
% o-in 
Conv..sup.2 
DHP HHP DHP/DHP + HHP 
No. hrs. 
.degree.C. 
% g % g % DIPB % Mol % 
Mol % 
% 
__________________________________________________________________________ 
0 40 85-87 
78.1 
65.6 
83.2 
283 55.0 
N.D..sup.3 
63.2 
12.0 3.3 78.4 
1 24 85-87 
81.2 
70.0 
82.9 
302 62.1 
N.D..sup.3 
46.8 
11.5 3.7 75.7 
2 24 87 70.6 
60.5 
75.5 
305 54.0 
N.D..sup.3 
39.9 
8.2 4.3 65.6 
3 24 87-89 
70.4 
62.3 
76.5 
304 53.4 
N.D..sup.3 
40.8 
8.6 4.7 64.7 
4 24 89 64.8 
63.1 
70.0 
303 52.1 
N.D..sup.3 
44.4 
7.8 6.0 56.5 
5 24 87-88 
62.1 
67.5 
71.4 
298 50.8 
N.D..sup.3 
47.0 
7.8 5.9 56.9 
6 24 87 64.3 
65.3 
70.7 
301 49.8 
N.D..sup.3 
43.2 
7.5 6.0 55.6 
7 24 87 64.1 
63.4 
67.2 
300 49.3 
N.D..sup.3 
46.5 
6.5 5.1 48.2 
8 24 87 55.1 
58.2 
62.8 
305 44.7 
N.D..sup.3 
44.3 
4.5 4.7 48.9 
9 32 85-87 
36.1 
47.4 
32.9 
310 28.5 
9.3 40.2 
2.3 2.1 52.3 
Av. 1-7 68.2 
64.6 
73.5 
302 53.1 44.1 
8.27 5.10 
61.9 
Av. 1-9 63.2 
62.0 
67.8 
303 49.4 43.7 
7.19 4.72 
60.4 
__________________________________________________________________________ 
.sup.1 By iodometric titration. 
.sup.2 Calculated from HPLC analysis. 
.sup.3 Not determined. 
TABLE IX 
__________________________________________________________________________ 
DHP/HHP From Commerical m-DIPB, 80% Recycle 
__________________________________________________________________________ 
Conditions DHP/HHP MHP/DIPB Recycle 
Recycle 
time 
temp. 
MHP.sup.1 
wt DHP.sup.1 
wt MHP.sup.1 
% o-in 
No. hrs. 
.degree.C. 
% g % g % DIPB 
__________________________________________________________________________ 
0 40 85-86 
71.2 
75.6 
81.4 
280 60.3 
N.D..sup.4 
1 24 85 67.9 
48.7 
82.1 
319 56.0 
3.0 
2 24 85 72.8 
59.2 
83.6 
314 58.8 
3.3 
3 32 85 86.0 
74.4 
86.9 
303 62.6 
4.2 
4 32 85 80.2 
72.2 
84.8 
300 61.6 
4.0 
5 32 85 81.4 
73.4 
85.1 
302 61.7 
5.2 
6 32 85 75.2 
75.8 
84.6 
298 60.4 
5.4 
7 32 85 81.1 
76.3 
84.9 
298 59.7 
5.1 
8 32 85 83.4 
81.8 
83.1 
305 59.9 
4.6 
9 32 85 78.1 
76.6 
84.9 
296 58.9 
4.3 
Av. 1-9 78.5 
70.9 
84.4 
304 60.0 
4.3 
__________________________________________________________________________ 
Conditions DIPB 
Net Production.sup.2 
Recycle 
time 
temp. 
Conv..sup.2 
DHP HHP DHP/DHP + HHP 
Yield,.sup.3 
No hrs. 
.degree.C. 
% Mol % 
Mol % 
% % 
__________________________________________________________________________ 
0 40 85-86 
75.6 
15.3 
3.0 83.6 93.4 
1 24 85 34.2 
7.2 2.4 75.0 92.3 
2 24 85 45.0 
8.9 3.6 71.2 94.7 
3 32 85 65.8 
14.7 
3.7 79.9 92.0 
4 32 85 50.5 
10.3 
3.9 72.5 95.3 
5 32 85 57.9 
12.7 
4.1 75.6 93.9 
6 32 85 53.1 
11.3 
4.0 73.9 95.6 
7 32 85 52.2 
12.3 
4.5 73.2 87.5 
8 32 85 54.9 
13.2 
3.7 78.1 90.9 
9 32 85 52.9 
11.6 
4.2 73.4 92.4 
Av. 1-9 85 51.8 
11.4 
3.8 75.0 92.8 
__________________________________________________________________________ 
.sup.1 By iodometric titration. 
.sup.2 Calculated from HPLC analysis. 
##STR6## 
.sup.4 Not determined. 
Hydroperoxidation of m-DIPB containing 1.2% o-isomer with 80% recycle of 
unreacted DIPB produced encouraging results as shown in Table VII. As the 
recycles progressed the decreases in % final MHP was less significant and 
the average weight of the DHP/HHP fraction was 61.2 g for the 10 cycles. 
More importantly, the average % DHP by titration of the DHP/HHP fraction 
was 76.9%, compared to 67.8% for the 100% recycle series, as shown in 
Table VIII. Diverting 20% of the recycle DIPB was observed to have raised 
the % DHP in the DHP/HHP product nearly 10%. 
The MHP-DIPB fraction recovered from Recycle 9 (See Table VIII) was 
distilled to recover unreacted m-DIPB. Analysis of the recovered m-DIPB by 
GLC showed it to have 9.3% o-isomer and 4.8% 1,1,3-trimethylindane (TMI) 
as impurities. It supports the conclusion that the deterioration in m-DIPB 
hydroperoxidation with increasing recycles is caused by the build-up of 
o-DIPB concentration in the recycles. Similarly, the mol % DHP/DHP+HHP 
determined by HPLC was 72.2%, compared to 60.4%. Therefore, it is 
concluded that hydroperoxidation with 80% recycle of DIPB produces higher 
selectivity to desirable hydroperoxides (DHP+HHP). 
It was concluded, based on the data of Examples 6 and 7, that m-DIPB is 
hydroperoxidized to a 3:1 mixture of m-DHP/m-HHP product in about 95% 
selectivity in a cyclic batch operation at 85.degree. C. and 1 atm, at a 
DIPB conversion of 45-55% per cycle, provided the concentration of 
o-isomers in the recycle is kept below about 6%. 
In the cyclic batch hydroperoxidation of Example 8 using commercial m-DIPB, 
a feed containing 50 mol % m-DIPB, 40 mol % MHP, 5 mol % MCL, and 2.5 mol 
% was oxidized to produce 25 mol % of m-DHP/m-HHP product and 25 mol % 
unreacted m-DIPB of the 25 mol % recovered DIPB, 20 mol % was recycled to 
the hydroperoxidation and 5 mol % was removed for returning to the 
manufacturer. Results shown in Table IX show that there was practically no 
change in final MHP concentration after nine cycles of hydroperoxidation. 
The slight variation in final MHP concentration was probably caused by 
temperature fluctuation since a constant temperature bath was not used. 
Neither the DHP concentration of DHP/HHP fraction determined by titration 
nor the value of % DHP/DHP+HHP determined by HPLC analysis changed very 
much with the number of recycles. Most importantly, the concentration of 
o-DIPB in the recycle DIPB stream remained in the range of 3.0 to 5.4%, 
well below the maximum allowable impurity level of 6.0%. In other words, 
hydroperoxidation of m-DIPB is not deteriorated unless there is a build-up 
of o-DIPB concentration in the recycle stream. The average yield of 
DHP/HHP product was 92.8% calculated from the equation: 
##EQU2## 
Conversion of m-HHP to m-DHP 
Hydroperoxidation of m-DIPB produces almost a 3:1 mixture of m-DHP/m-HHP. 
Unfortunately this product cannot be used to obtain good resorcinol yield. 
Almost all acid-catalyzed decompositions of m-DHP to resorcinol require 
the use of pure DHP. Since there is no practical way to separate HHP from 
DHP and HHP is also decomposed by an acidic catalyst, a way must be 
developed to convert HHP to DHP before the acid-catalyzed decomposition is 
made. A modified version of the process described in U.S. Pat. Nos. 
4,238,570 and 4,267,387 was determined to be advantageous. The prior art 
process uses a heterogenous system of hydrogen peroxide in an aromatic 
hydrocarbon solvent and stresses the need to continuously remove 
co-product water by azeotropic distillation. 
The hydrogen peroxide oxidation step of the present invention does not 
continuously remove water. It has been determined to be advantageous to 
evaporate the MIBK from the m-DHP/m-HHP fraction because the presence of 
MIBK requires the use of excess amounts of hydrogen peroxide to overcome 
the reaction between MIBK and hydrogen peroxide. Following evaporation of 
MIBK, the m-DHP/m-HHP fraction is preferably dissolved in toluene which 
does not necessitate the use of excess hydrogen peroxide. Stoichiometric 
amounts of hydrogen peroxide can be used in the instant process. 
Concentrations as low as 13-18% hydrogen peroxide have been used to yield 
88.3% resorcinol on DHP+HHP. Higher concentrations can also be used, as in 
the Example below. Small, effective amounts of sulfuric acid are 
preferably added as a catalyst. 
EXAMPLE 9 
In a 100 ml 3-neck flask equipped with a stirrer, thermometer, and reflux 
condenser was placed 7.5 g of DHP/HHP mixture dissolved in 75 ml toluene. 
The flask was heated in a water bath maintained at 40.degree. C. with 
stirring. An aqueous solution consisting of 2.55 g 50% hydrogen peroxide, 
0.953 g 96% sulfuric acid, and 3.552 g water, which is equal to 1.5 M 
[H.sub.2 SO.sub.4 ], 6.0 M [H.sub.2 O.sub.2 ], and 400% excess hydrogen 
peroxide based on 21 mol % HHP in DHP/HHP mixture, was added to the flask 
and the mixture was stirred vigorously at 40.degree. C. for one hour. It 
was cooled to room temperature and the mixture was transferred to a 
sep-funnel. The decomposition product was washed with 2 ml water and 
neutralized with 5 drops of 10% sodium carbonate (Na.sub.2 CO.sub.3). It 
was dried with 5 g 4A.degree. molecular sieves at room temperature for 45 
min and the sieves were removed by filtration. The toluene solution was 
put back in the 3-neck flask and heated to 50.degree. C. The water bath 
was removed and a boron trifluoride catalyst was introduced below the 
liquid surface until a vigorous exothermic reaction took place. If 
necessary, the flask was cooled with an ice-water bath to keep the 
temperature at 50.degree. C. After the reaction had subsided, the flask 
was heated in a water bath at 50.degree. C. for 45 min to complete the 
decomposition. After cooling to room temperature, the reaction mixture was 
transferred to a sep-funnel and 50 ml water was added. A 10% aqueous 
sodium carbonate solution was added dropwise until the aqueous phase 
became neutral after vigorous shaking. The toluene phase was separated and 
the aqueous phase was extracted three times with 50 ml each of ether to 
recover resorcinol. The combined ether and toluene solutions were 
evaporated to dryness and the residue was analyzed by HPLC to determine 
its resorcinol content. 
TABLE X 
______________________________________ 
Resorcinol Yields With and Without H.sub.2 O.sub.2 Oxidation of DHP/HHP 
% Yield % Yield 
% w/o H.sub.2 O.sub.2 Oxidn. 
w/o H.sub.2 O.sub.2 Oxidn. 
DHP (on (on DHP + 
(on (on DHP + 
Run No. 
Purity DHP) HHP) DHP) HHP) 
______________________________________ 
1 100.0 96.6 96.6 93.1 93.1 
2 81.0 82.1 70.3 103.6 88.6 
3 79.4 82.4 70.7 104.6 89.8 
4 75.1 74.4 60.0 112.1 92.0 
5 70.0 70.4 54.0 112.3 86.2 
6 54.1 76.6 48.5 125.8 79.5 
7 67.5 77.4 58.5 116.3 87.8 
8 68.9 76.9 57.9 120.5 90.8 
9 67.4 85.0 61.8 116.9 85.1 
Average.sup.1 
76.7 78.4 61.9 112.3 88.6 
______________________________________ 
.sup.1 Average of Runs 2-5 and 7-9 (Runs 1 and 6 were excluded since they 
were not considered to be typical DHP purities in a commercial operation. 
 
Run 1 of Table X (93.1% on DHP) represents the maximum resorcinol yield 
since the concentration of HHP in the DHP/HHP sample is approximately 
zero. The results of Table X show a significant increase in resorcinol 
yield after the hydrogen peroxide treatment. The resorcinol yield on 
DHP+HHP varies from 79.5 to 92% indicating 70 to 95% of the HHP in the 
original feed had been converted to DHP by the hydrogen peroxide 
treatment. Since the feed of these experiments was obtained directly from 
the hydroperoxidation of m-DIPB and contained impurities which cannot be 
oxidized to DHP, these resorcinol yields can be considered as being close 
to the maximum attainable yields. 
The recovered hydrogen peroxide solution is mixed with 50% hydrogen 
peroxide stock solution to prepare the 6.0 M hydrogen peroxide feed for 
the next oxidation of DHP/HHP mixture. The oxidized DHP/HHP product in 
toluene can be dried by any suitable known procedure such as with a 
molecular sieve. It has been determined that water removal is important to 
the decomposition of m-DHP with boron trifluoride as shown in Example 10 
and Table XI. 
Decomposition of m-DHP To Resorcinol 
The last step of the 3-step hydroperoxidation process is the decomposition 
of m-DHP in the presence of acidic catalysts to co-produce resorcinol and 
acetone. In the current commercial process, this is done in the presence 
of a small amount, in the percent composition range, of a Bronsted acid 
catalyst, generally a mineral acid, such as sulfuric acid. The 
decomposition product, usually dissolved in an organic solvent, is 
neutralized with dilute alkali and then distilled to obtain crude 
resorcinol. 
An improved method for the decomposition of m-DHP using a Lewis acid 
catalyst selected from the group consisting of boron trifluoride and 
stannic chloride, preferably anhydrous boron trifluoride or its complexes, 
is provided by the present invention. From the results presented in Table 
XII it is shown that the activity of the boron trifluoride catalyst is 
higher than the conventional catalysts. This is a definite advantage for 
using BF.sub.3 in the decomposition of m-DHP. The decomposition of m-DHP 
has been achieved using significantly smaller amounts of catalyst, e.g. 10 
to 100 ppm, and as low as 10 to 50 ppm, at a temperature of about 
50.degree. C. 
The m-DHP fraction must be dried as described above prior to decomposition 
with boron trifluoride. It has been observed that the higher the moisture 
content, the greater amount of catalyst is required. Water decreases the 
activity of boron trifluoride by producing a less active catalytic species 
which favors the production of undesirable decomposition products. An 
approximate upper limit of water content has been determined to be 0.1 wt 
%. 
EXAMPLE 10 
In a 200 ml flask was placed 75 ml of solvent (toluene or MIBK) and 15 ml 
of an aqueous solution containing 6 M H.sub.2 O.sub.2 and 1.5 M H.sub.2 
SO.sub.4. After stirring at room temperature for 30 min., the aqueous 
phase was separated and the solvent was dried with 5 g drying agent 
(anhydrous Na.sub.2 SO.sub.4 or 4 A.degree. Molecular Sieves) at 
50.degree. C. for 30 min. The solvent was used to decompose 7.5 g of m-DHP 
(&gt;90% purity) using as much BF.sub.3 -Et.sub.2 O catalyst as needed to 
start the decomposition of DHP at 50.degree. C. After one hour of 
reaction, the reaction mixture was cooled at room temperature and the 
solvent was evaporated at 40.degree. C. and 4 mm pressure using a Rinco 
evaporator. The recovered solid was weighed and analyzed by HPLC for 
resorcinol. Resorcinol yield was calculated from the sample weight and 
resorcinol wt. % in the HPLC analysis. The results are shown in Table XI. 
TABLE XI 
______________________________________ 
Effect of H.sub.2 O in Solvent on Resorcinol Yield 
Amount 
BF.sub.3 -Et.sub.2 O 
Resor- 
Run Drying % H.sub.2 O in 
used cinol 
Nos. Solvent Agent Solvent (ml) yield, % 
______________________________________ 
1 Toluene none 0.029 0.035 75 
2 Toluene Na.sub.2 SO.sub.4 
0.024 0.030 78 
3 Toluene 4A Sieves 0.012 0.025 83 
4 MlBK none 2.5 0.20 52 
5 MlBK Na.sub.2 SO.sub.4 
1.8 0.30 54 
6 MlBK 4A Sieves 0.065 0.030 80 
______________________________________ 
.sup.1 Determined by Karl Fisher method. 
EXAMPLE 11 
In a 100 ml 3-neck flask equipped with a stirrer, thermometer, and reflux 
condenser was placed 15 g of m-DHP dissolved in 75 ml of MIBK (or 
toluene). The flask was heated in a water-bath maintained at 50.degree. C. 
with stirring. Using a microliter syringe, 25 microliters of boron 
trifluoride etherate (BF.sub.3.Et.sub.2 O) was charged to the flask to 
start the decomposition of m-DHP to resorcinol. After one hour of 
reaction, the reaction mixture was cooled to room temperature and a small 
sample was analyzed by GLC. The reaction mixture was immediately 
transferred to a Rinco evaporator and the solvent was evaporated at 
40.degree. C. and 4 mm pressure (higher pressure if toluene is used as 
solvent). The recovered solid was weighed and analyzed by HPLC. Resorcinol 
yield was calculated from the sample weight and resorcinol wt % in the 
HPLC analysis. 
Table XII shows the yields of resorcinol from the decomposition of m-DHP 
containing only a small percentage of m-HHP. 
TABLE XII 
______________________________________ 
Effect of Solvent and m-DHP Purity on Resorcinol Yield 
Run Amt. BF.sub.3.sup.2 
Resorcinol Yield, % 
No. % m-DHP.sup.1 
Solvent .mu.l. by GLC by HPLC 
______________________________________ 
1 95 MIBK 25 101.1 98.0 
2 90 Tol 25 95.9 95.9 
3 80 MIBK 30 85.3 84.3 
4 70 MIBK 40 77.9 72.7 
5 90 Tol .sup. 50.sup.3 
61.1 ND.sup.4 
______________________________________ 
.sup.1 Percent mDHP from iodometric titration. 
.sup.2 BF.sub.3 etherate. 
.sup.3 Ninetysix (96) % H.sub.2 SO.sub.4 was used in this experiment. 
.sup.4 Not determined. 
Analysis of the decomposition product, either by CLG or HPLC, indicates a 
high selectivity to resorcinol. In the prior art hydroperoxidation 
process, it is difficult to obtain resorcinol in high purity. The 
advantage of using a boron trifluoride catalyst is evident. Even with less 
pure m-DHP (other components are m-HHP and m-MHP), resorcinol yields are 
still better than the decomposition of pure m-DHP (90%) with a sulfuric 
acid catalyst. 
Table XIII summarizes the decomposition of m-DHP/m-HHP mixtures obtained 
directly from the caustic extraction of m-DIPB hydroperoxidation products. 
Yields of resorcinol based on m-DHP present were 21.7% to 33.7% lower than 
the theoretical yields. In general, when low purity m-DHP is decomposed, 
there is a lower resorcinol yield. This is not surprising because it 
usually takes 2 to 3 days to finish the work-up procedure, and resorcinol 
is a very reactive compound and probably forms secondary products, 
especially in the presence of an acidic catalyst. 
TABLE XIII 
______________________________________ 
Variation of Resorcinol Yield with m-DHP Purity 
m-DHP Purity, l 
Product Purity, 
% Yield 
Run No mol % % Resorcinol 
(on DHP) 
______________________________________ 
1 100 86.9 91.5 
2 94 75.0 82.7 
3 78 48.0 72.7 
4 74 31.0 54.7 
5 72 30.0 54.6 
6 68 22.5 34.3 
7 52 21.5 49.3 
______________________________________ 
.sup.1 Mol % mDHP determined by HPLC. 
EXAMPLE 12 
The following procedure was used to obtain more accurate data for the 
decomposition of m-DHP/m-HHP mixture using a boron trifluoride catalyst. 
In a 100 ml 3-neck flask equipped with a stirrer, thermometer, and reflux 
condensor was placed 7.5 g m-DHP/m-HHP mixture dissolved in 75 ml toluene. 
The flask was heated in a water-bath to 50.degree. C. with stirring. After 
removing the water-bath, 15-100 microliters of boron trifluoride etherate 
was introduced below the liquid surface, using a microliter syringe and a 
long needle. The flask was cooled with an ice-water bath to remove the 
exothermic heat of reaction. The flask was maintained at 50.degree. C. for 
45 minutes and then cooled to room temperature. The contents were 
transferred to a 150 ml sep-funnel and 50 ml water was added. After 
shaking for a few minutes, a 10% aqueous sodium carbonate solution was 
added dropwise until the pH of the aqueous phase was neutral (pH=7). The 
toluene phase was separated and the aqueous phase was extracted three 
times with 50 ml portions of ether. The combined ether and toluene 
solutions were evaporated to dryness and the residue was weighed and 
analyzed by HPLC, using a standard technique for analysis of resorcinol. 
Table XIV shows the effect of catalyst neutralization (with 10% aqueous 
Na.sub.2 CO.sub.3) on the yields of resorcinol using boron trifluoride as 
catalyst. It shows not only that the yields are increased by neutralizing 
the boron trifluoride catalyst immediately after the decomposition of 
m-DHP, but also that if acetone is used as solvent and boron trifluoride 
catalyst is not removed after the decomposition, there will be a large 
reduction in resorcinol yield indicating a possible reaction between 
resorcinol and acetone. 
TABLE XIV 
______________________________________ 
Effect of Catalyst Neutralization on Resorcinol Yield 
Product Yield, 
% Catalyst 
Run m-DHP,.sup.1 Purity, (on Neutral- 
No % Solvent % Resorcinol 
DHP) ization 
______________________________________ 
1 100 Toluene 86.9 91.5 w/o neut. 
2 100 Toluene 85.5 .sup. 85.5.sup.2 
w neut. 
3 100 Acetone 65.5 75.0 w/o neut. 
4 100 Acetone 90.0 90.1 w neut. 
5 74 Toluene 21.5 36.9 w/o neut. 
6 74 Toluene 29.0 50.3 w neut. 
7 74 Acetone 10.5 19.9 w/o neut. 
8 74 Acetone 44.5 72.6 w neut. 
______________________________________ 
.sup.1 % mDHP was determined by HPLC. 
.sup.2 The lower yield with neutralization may be due to mechanial losses 
during the washing step. 
In order to minimize uncertainties in resorcinol yield due to the loss of 
resorcinol during work-up of m-DHP decomposition products, the following 
GLC analysis method was used to obtain improved resorcinol yields. Results 
are shown in Table XV. 
EXAMPLE 13 
The decomposition of 7.5 g m-DHP/m-HHP sample in 75 ml solvent with a small 
amount of boron trifluoride etherate was made using the same procedure as 
described. After the decomposition, the solution was cooled to room 
temperature with an ice-water bath. The product was transferred to a 250 
ml volumetric flask and diluted to 250 ml with toluene. An external 
standard was prepared by dissolving a weighed quantity of pure resorcinol 
(usually 13.5 g) in approximately 10 ml acetone and then diluting it to 
250 ml with toluene. The two solutions were analyzed by GLC using the 
response factor of the external standard to determine the weight % 
resorcinol. A 10'.times.1/8" SS column packed with 10% OV17 at 210.degree. 
C. was used for GLC analysis. 
TABLE XV 
______________________________________ 
Decomposition of m-DHP with BF.sub.3 Catalyst 
% DHP Resorcinol Yield,.sup.2 
Run No. in Sample.sup.1 
Solvent mol % (on DHP) 
______________________________________ 
1 100.0 MIBK 96.6 
2 81.0 MIBK 82.1 
3 79.4 MIBK 82.4 
4 75.1 MIBK 74.4 
5 70.0 MIBK 70.4 
6 54.1 MIBK 76.6 
7 100.0 Toluene 96.4 
8 67.5 Toluene 77.4 
9 68.9 Toluene 76.9 
10 67.4 Toluene 85.0 
______________________________________ 
.sup.1 Percent DHP was determined by HPLC analysis. Its accuracy was 
estimated to be .+-. 2%. 
.sup.2 Based on GLC analysis. 
Compared to currently available technology, the results of m-DHP 
decomposition catalyzed by boron trifluoride (See Table XV) are excellent. 
The % resorcinol yields based on % DHP present in the sample are 70.4% to 
96.6% depending on the purity of m-DHP. The yields are higher when toluene 
is used as solvent, indicating a possible reaction between resorcinol and 
MIBK. These yields, however, are still higher than those when concentrated 
sulfuric acid is used as catalyst. Run 5 of Table XII gave a 61.1% 
resorcinol yield when 50 microliters of 96% sulfuric acid was used as 
catalyst, compared to a 95.9% yield when 25 microliter of boron 
trifluoride was used. 
For comparison, decomposition of m-DHP in the presence of several different 
Lewis acid catalysts was investigated and the results are show in Table 
XVI. Both boron trifluoride (BF.sub.3) and stannic chloride (SnCl.sub.4) 
gave the best yields. Ferric chloride (FeCl.sub.3) also gave an acceptable 
yield. Boron trifluoride is, however, preferred in view of the potential 
environmental problems associated with stannic chloride. Decompositions 
with aluminum chloride (AlCl.sub.3) gave a very poor yield of resorcinol. 
Therefore, not all Lewis acids are good catalysts for the decomposition of 
m-DHP. 
TABLE XVI 
______________________________________ 
Evaluation of Lewis Acids for m-DHP Decomposition 
DHP, Resorcinol 
Run Purity Catalyst Yield, % 
No. % Solvent Type Amount (on DHP) 
______________________________________ 
1 100 Toluene BF.sub.3.sup.2 
20 .mu.l 
96.5 
2 100 Toluene SnCl.sub.4 
25 .mu.l 
100.6 
3 100 Toluene FeCl.sub.13 
0.05 g 86.7 
4 100 Toluene AlCl.sub.3 
0.5 g 14.0 
5 100 Toluene SO.sub.3 l 88.0 
6 81 MIBK BF.sub.3.sup.2 
170 .mu.l 
82.1 
7 81 Toluene SnCl.sub.4 
100 .mu.l 
79.0 
______________________________________ 
.sup.1 Used 3.8 g of a 0.7% SO.sub.3 in acetone. 
.sup.2 BF.sub.3 etherate. 
Another advantage of the boron trifluoride catalyst is its low activity in 
promoting the secondary reactions of the resorcinol that is produced. A 
minute quantity of boron trifluoride used to decompose m-DHP is not 
sufficient to promote the reaction between resorcinol and 
isopropenylphenol, for example. In addition, the boron trifluoride 
catalyst can readily be removed from the organic phase by washing with a 
small amount of aqueous sodium hydroxide. Thus, the crude resorcinol 
obtained by the boron trifluoride-catalyzed decomposition of m-DHP does 
not require a specific purification process. This is considered to be an 
advantage of the boron trifluoride-catalyzed decomposition of m-DHP 
provided by the process of the present invention.