JPH04327545A - Method of manufacturing diisopropylbenzene - Google Patents

Abstract

PURPOSE: To advantageously obtain diisopropylbenzene useful as an antioxidant, a stabilizer, etc., by using a zeolite β catalyst more excellent in reaction selectivity, reaction activity and stability than a known catalyst for disproportionation reaction of isopropylbenzene.

CONSTITUTION: Isopropyl-contg. starting material is brought into catalytic reaction at 90-250°C under about 1-100 atm pressure in the presence of a zeolite βcatalyst, preferably a hydrogen anion type zeolite β catalyst in which the molar ratio of SiO₂ to Al₂O₃ is 10-150 to advantageously obtain the objective diisopropylbenzene useful also as a developer and an intermediate of polycarbonate. This method is preferably carried out in a continuous fixed bed reactor system and a flow of gaseous nitrogen is preferably passed through the reactor system so that the molar ratio between the flow and the starting material is regulated to (0-5):1. In this case, the starting material is preferably passed through the catalyst at 0.2-50 ghr^-1gcat^-1 rate and the reaction temp. is preferably 100-180°C. The stability of the catalyst is improved by pretreatment with steam.

COPYRIGHT: (C)1992,JPO

Description

Description: TECHNICAL FIELD The present invention relates to a method for producing diisopropylbenzene. Specifically, the present invention relates to a method for producing diisopropylbenzene by catalytic conversion of a raw material containing isopropyl. BACKGROUND OF THE INVENTION Diisopropylbenzene, especially the m- and p-diisopropylbenzene isomers, is an antioxidant, stabilizer, and an important intermediate for developers and polycarbonates. Further, diisopropylbenzene can also be made into diisopropylenebenzene, which has a structure similar to styrene monomer, by dehydrogenation. For example, H. A. Covin &
J. Muse,”Polymers Diisop
"ropenylbenzene" Chemtech
, 500 (1986), diisopropylenebenzene is a more versatile intermediate than styrene monomer due to its diversity in structural modification. Diisopropylbenzene has also been developed and applied to process plastics, epoxy resins, and polyurethanes, so the production of diisopropylbenzene is research with great industrial value. [0003] There are two general methods for producing diisopropylbenzene as shown below. The first method uses a catalyst to attach the propyl group directly to benzene. Catalysts that can be used include Friedel-Crafts, ZSM-5, ZSM-12, and the like. The second method is a disproportionation reaction of isopropylbenzene, in which two molecules of isopropane are reacted with each other in the presence of a catalyst to produce one molecule of benzene and one molecule of diisopropylbenzene. Generally, the production method using the disproportionation reaction has better reaction selectivity than the alkylation reaction. USSR Patent No. 192,109 describes AlCl
3 discloses a method for producing diisopropylbenzene by disproportionation reaction of isopropylbenzene in the presence of a catalyst. This AlCl3 catalyst not only has poor isomer selectivity but also causes problems of environmental pollution. U.S. Patent No. 3,780
, No. 123 discloses the disproportionation reaction of alkylbenzenes. The reaction is carried out in the presence of a composite catalyst, which is composed of H-type mordenite, aluminum oxide, and Group VIII metal sulfide. [0005]W. W. Kaeding is a J. C
atal. No. 120, p. 409 (1989)
”Shape-SelectiveReactions
with Zeolite Catalysts V
II. Alkylation and Dispro
position of Cumene to P
roduce Diisopropylbenzene
disclosed a method for producing diisopropylbenzene by catalytic reaction of isopropylbenzene in the presence of ZSM-12 catalyst.The selectivity of this ZSM-12 catalyst for isopropylbenzene disproportionation reaction is
Although it is superior to catalysts, there is still room for improvement. US Pat. No. 3,308,069 discloses zeolite beta catalysts. The chemical composition calculation formula is as follows. [Math. 1]■ [XNa(1.0 ±
0.1-X)]TEA]AlO2 ・YSiO2 ・
WH2O In the formula 1, X is smaller than 1. Y is greater than 5 but 10
Less than 0. W is 4 or less, and TEA represents tetraethylammonium ion. Generally, when pretreated with steam, zeolite Y
The increase in the SiO2 /Al2 O3 molar ratio of the catalyst is also described in US Pat. No. 3,292,192. Therefore, steam pretreatment increases the acid strength of the zeolite Y catalyst and reduces the caking rate and stability. In the present invention, diisopropylbenzene was first produced by a disproportionation reaction of isopropylbenzene using a zeolite β catalyst. This zeolite β catalyst has better reaction selectivity, reaction activity, and stability than the well-known isopropylbenzene disproportionation reaction catalyst. DESCRIPTION OF THE INVENTION [0008] The present invention provides a method for producing diisopropylbenzene, which is characterized in that a raw material containing isopropyl is subjected to a catalytic reaction at 90-250°C in the presence of a zeolite β catalyst. The zeolite β catalyst used in the method of the present invention is preferably of the H anion type, and its SiO2 /Al2
The molar ratio of O3 is between 10-150. The method of the present invention is preferably carried out in a continuous fixed bed reactor system, in which the isopropyl raw material passes through the weight space of the zeolite β catalyst at a rate of 0.2-50 g hr-1 g cat-
It is 1. The present invention relates to a method for producing diisopropylbenzene. A catalytic reaction is performed on a raw material containing isopropyl at 90-250°C in the presence of a zeolite β catalyst. The catalytic reaction of the method of the present invention is mainly a disproportionation reaction of isopropylbenzene, in which 2 moles of isopropylbenzene are reacted in the presence of a catalyst to produce 1 mole of benzene and 1 mole of diisopropylbenzene. [0010] The paper previously published by the present inventor “Disp
rotation of Toluene
and Trimethylbenzene and T
hair translation over
Zeolite Beta”, Ind. Eng.
Chem. Research, 1990.9 discloses that a hydrogen anion type zeolite β catalyst exhibits excellent reaction activity, selectivity and stability in the disproportionation and transalkylation reactions of toluene and trimethylbenzene. Therefore, we believe that the zeolite β catalyst applied to the present invention has excellent reactivity even in the hydrogen anion type. [0011] As a method applied to the production of the zeolite β catalyst according to the method of the present invention, a constant temperature hydrothermal method (hydro-t
SiO2-Al
A crystalline solid is prepared from a mixture of 2O3-tetraethylammonium hydroxide-water. Pariente et al. Appl. Catal. Third
1, page 35 (1987) “Cry
Stallization Mechanism of
ZeoliteBeta from (TEA)2
O, Na2O and K2O Containi
ng AluminosilicateGels”. The content of this paper is used as reference for the present invention. The solid product obtained each time was filtered, washed with water, and dried overnight at 120 °C, so that the molar ratio of SiO2 /Al2 O3 The obtained product was baked at 450°C-660°C for 2-48 hours and then heated with NH4
Ion exchange with NO3 solution, filtering, washing, drying, and/or grinding to particles of desired size and shape, and/or further grinding to particles of desired size. [0012] The reaction temperature in the method of the present invention is 100°C.
It is preferably between -180°C. The reaction strength is not particularly limited, but is preferably about 1 atmospheric pressure. The reaction atmosphere in the method of the present invention is also not particularly limited. For example, no gas is added or N2, H2, etc. are added to the reactor. Generally, the molar ratio between the added gas and the isopropylbenzene raw material is 0.
05 or higher. Although the process of the invention can be carried out in any known reactor system, the preferred embodiment of the invention uses a continuous fixed bed reactor system, and the weight hourly space velocity of the feedstock passing through the fixed bed reactor system is (WHSV) is 0.2-5
At 0g hr-1gcat-1, 2.8-3.4g h
Preferably, it is between r-1gcat-1. [0013] The method of the present invention will be explained in more detail by the following examples, which are for illustrative purposes only.
It is not intended to limit the scope of the invention. [Example 1]: Production of zeolite β, ZSM-5, H-type mordenite, and zeolite HY catalyst Zeolite β catalyst was manufactured using a constant temperature hydrothermal method using SiO2-Al2
Crystals are formed from a mixture of O3-tetraethylammonium hydroxide-water, washed with water, and dried overnight at 120°C. When the obtained product was analyzed using a Simens D-500 X-ray diffractometer, the X-ray powder diffraction pattern was found in the "Dispropositionation" published by the present inventor.
of Toluene and Trimethylb
Enzene and Their Transalk
ylation over Zeolite Beta
"As shown in Figure 1 of the paper. Also, the molar ratio of SiO2 /Al2 O3 measured by inductively coupled plasma is 15.3. [0014] After baking the above dried product at 450°C for 6 hours, , carry out the following ion exchange: (1) solid and 1 at 80 °C
N NH4 NO3 solution at a solid/solution weight ratio of 1:
20 for 8 hours, (2) collecting the solid by filtration;
(3) Wash the solid with hot deionized water. After repeating this ion exchange process six times, this NH4 + ion exchange solid was dried at 120°C overnight, and then baked in air at 450°C for 6 hours to granulate this H-type zeolite.
The particles were made into 2-20 mesh particles. [0015] H-type mordenite (HM) is a Stream
Chemicals Co. Purchased directly from. ZS
M-5 is “Kinetic Stud” by Chao et al.
ies on the Formation of Z
eolite ZSM-5”Chem.Soc.Fa
raday Trans. ,1, 77, 547(1
981). Zeolite HY is manufactured by Stream Chemicals Co. NaY purchased from. ZSM-5 and NaY are N of the above zeolite β.
H4 + Same as ion exchange, 12- of H type zeolite
The particles were made into 20 mesh particles. [Example 2]: Disproportionation reaction of isopropylbenzene The reaction was carried out in a continuous fixed bed reactor. 2.54 grams of zeolite β produced in Example 1 above and 4.65 grams of ceramic flakes were mixed and packed into a reactor,
After activation for 6 hours by passing hot air at 0° C., cooling to the desired reaction temperature by passing nitrogen. Isopropylbenzene, purchased from Jassen Chemical, is passed through the reactor with a metering pump and a separately metered stream of nitrogen is passed to give a nitrogen/isopropylbenzene ratio of 0.19 mole/mole. The reaction product flowing out of the reactor is collected every 15 minutes,
Dimethylsiloxane column, HP Ultra 1
Hewlett-Packard 589 equipped with
0 Analyzed by gas chromatography. The conversion rate XC of isopropylbenzene and the selectivity SD of the disproportionation reaction are defined as follows: [Formula 2] 3 In Equations 2 and 3, (isopropylbenzene, wt%)p and (DPB, wt%)p are the compositions of isopropylbenzene and dipropylbenzene (abbreviated as DPB), respectively, in the product stream. Indicates the ingredients. The results and conditions of the reaction are shown in Table 1. Table 1 also shows the results of a reaction in which HY, HM HZSM-5 was substituted for zeolite β under the same conditions. [Table 1] Reaction activity of disproportionation reaction in isopropylbenzene disproportionation reaction comparing different catalysts under low conversion rate,
Selectivity and stability 1H
-Beta HY HM
HZSM-52 reaction temperature (℃)
118 205 200
120 Conversion rate (wt%) 14.0
13.0 5.9 6.3
Selection rate (mol/mol) Disproportionation selection rate 0.99
0.95 0.93 0.69
Sense/Selfie Sense
1.0 1.05 1
．． 09 2.07 m/p-shirofluorescence 1.75 2.1
0 1.71 0.23 α
0.07
0.15 0.35...
Product yield (wt%) Benzene 4.50
4.21 1.95 2.9
2 Isopropylbenzene 86.05 8
7.04 94.10 93.69 n-
Propylbenzene 0.11 0.13
0.15 0.05 o-shiroisoprofil hsen...
0.19 0.10...
・M-Shield Sense
5.94 5.49 2.
28 0.52 p-isophrofluorescence 3.4 2.
62 1.33 2.28 p-n-
Profile - ISO profile reference
・・・ ・・・ ・・・
0.13 Other aromatics
... 0.32 0.09
0.41 1 WHSV: 3.4g hr -
1gcat-1, nitrogen/isopropylbenzene = 0.1
9 mol/mol, reaction time (time-on-stream)
m): 60 minutes 2 Reaction time: 30 minutes From the data in Table 1, the zeolite β catalyst exhibits the best reaction activity and selectivity in the isopropylbenzene disproportionation reaction. For example, when the reaction temperature is 118°C, the zeolite β catalyst conversion rate is 14.0, and the zeolite H
It is much larger than Y and HM, and the selectivity of the disproportionation reaction is 0.99, which is very close to 1, indicating that almost equimolar amounts of benzene and dipropylbenzene are produced. Aging of zeolite catalyst reaction activity is generally expressed by the following exponential formula. ##EQU00004## In the formula 4, Xt represents the conversion rate of isopropylbenzene when the reaction time is t. Xo represents the conversion rate when the reaction time is extrapolated to 0. α is a decline index, and the smaller the α value, the better the stability. For example, as shown in Table 1, the zeolite β catalyst has the best stability. Table 2 below shows the results of the reaction at a high conversion rate, ie, at a high reaction temperature. [Table 2] Reaction activity of disproportionation reaction in isopropylbenzene disproportionation reaction comparing different catalysts under high conversion rate,
Selectivity and stability 1H
-Beta HY HM
HZSM-52 reaction temperature (℃)
138 220 240
250 Conversion rate (wt%) 4
0.1 22.5 14.5
45.1 Caking rate [(g/g cat)%3]
4.72 4.54 6.62
... Selection rate (mol/mol) Disproportionation selection rate 0.98
0.91 0.95 0.90
Sense/Selfie Sense
1.06 1.16 1
．． 12 1.17m/p-silicon isophylfluorescence 2.05
2.18 2.01 1.81α
0
．． 23 0.14 0.31
... Product yield (weight %) Benzene 13.
5 7.74 4.95 15.
42 Isophyllense
59.88 77.53 85.
55 54.9n-Full Sense 0.10
0.17 0.14 0.32o-isopropylene sensitization
... 0.42 0.11
0.23m-Silver sensor
17.76 9.17
6.08 17.54 p-isopropylene sensitization 8.
68 4.21 3.03 9
．． 70 Other aromatics 0.
08 0.76 0.14 1
．． 891 WHSV: 3.4g hr-1gcat
-1, nitrogen/isopropylbenzene = 0.19 mol/
mol, reaction time: 60 minutes2 Data are from the above W.
W. A paper published by Kaeding et al. J. Cata
l. 120, 409 (1989). 3 The caking rate is measured at the reaction temperature with nitrogen after the reaction time is over.
After washing for a while, remove the amount of deposited coal tar with Dupont 9
51 Measured by thermogravimetry. Similarly, the data in Table 2 shows that zeolite β has a higher conversion rate than the Y type and mordenite type in the isopropylbenzene disproportionation reaction, and can maintain an excellent disproportionation selectivity. Shows no cracking products. Although the ZSM-12 type zeolite can obtain a conversion rate equivalent to that of zeolite β, its reaction temperature is much higher (110° C. higher) than that of zeolite β, so its reaction activity is far inferior to that of zeolite. Also, although zeolite β operates at higher conversion rates, the caking rate is still the same as Y type and lower than mordenite type. Therefore, when operated at the same temperature, the zeolite beta type exhibits a lower caking rate than the Y and mordenite types. This is because the β-type zeolite has superior stability. Therefore, zeolite β type has excellent reaction activity, selectivity and stability. [Example 3] The purpose of this example is to demonstrate that the zeolite β catalyst used in the method of the present invention improves the stability of the isopropylbenzene disproportionation reaction by the method of steam pretreatment. This is what I want to explain. The same procedure as in Example 2 is carried out except that the zeolite β catalyst in the reactor is pretreated with steam before introducing the isopropylbenzene raw material. Steam pretreatment involves pumping distilled water to a reactor with specific treatment conditions. After the pretreatment is completed, nitrogen is introduced into the reactor and flushed for 3 hours to remove residual vapors. The reaction results and conditions are shown in Table 3. [Table 3] Effect of steam pretreatment on reaction activity and stability of zeolite β catalyst 1
catalyst

unqualified
1 2 Steam pretreatment condition temperature (℃)
454
450 WHSV (g/hr gcat)
3.38
9.88 nitrogen/water (mol/mol)
0.18
0.18 hours (hr)
4
10 Reaction condition temperature (℃) 13
4 143 153
172 WHSV (g/hr gcat)
3.4 3.4 2.0
2.2 Conversion rate (wt%)
29.40 40.1 37.1
33.50 Caking rate (g/hr gca
t2) ... 6.47
... 5.92 Stability XO (wt%) 67.
4 100.0 55.2
34.50 α
0.19 0.23
0.09 0.01 Selection rate (mol/mol) SD (mol%) 98.
9 97.6 93.08
82.48 Sense/Profile Sense 1.10
1.06 1.27 1.40m/
p-shirofluorescence sensor
0.47 0.51 0.42
0.43 Product yield (wt%) Benzene 9
．． 45 13.5 13.22
12.61 Isopropylbenzene
70.65 59.88 62.95
66.51 n-Full Sense
0.12 0
．． 10 0.16 0.17o-Siisopropylene Sense
13.35 17.76 16.2
0 12.88 m-Shirofluorescence...
・・・ ・・・ 0.20
p-shirofluorescence sensor
6.27 8.68 6
．． 87 5.57 Other aromatics
0.16 0.08
0.40 2.071 Isopropylbenzene/nitrogen = 14.5 mol/mol, reaction time: 6
0 minutes [0024] As clearly shown from the data in Table 3 above,
Steam pretreatment improves the stability of the zeolite β catalyst, but at the same time loses the reactive activity of the fraction.

Claims (8)

[Claims] Claim 1: A method for producing a mixture containing diisopropylbenzene by catalytic reaction of an isopropyl raw material, an improvement of which involves carrying out a catalytic reaction of the isopropyl-containing raw material at 90-250°C in the presence of a zeolite β catalyst. Characteristic method for producing diisopropylbenzene. [Claim 2] The zeolite β catalyst is a hydrogen anion type, and its SiO2/Al2O3 molar ratio is 10.
-150. 3. The method of claim 1, wherein the catalytic reaction is carried out in a continuous fixed bed reactor system. 4. The method of claim 3, wherein a nitrogen stream is separately passed through the reactor system, and the molar ratio between the nitrogen stream and the isopropyl feedstock is 0-5. 5. The speed at which the isopropyl raw material passes through the weight space of the zeolite β catalyst is 0.2-50 g hr-1gc.
5. The method of claim 4, wherein at-1. 6. The method of claim 5, wherein the reaction temperature is between 100-180°C. 7. The method of claim 1, wherein the catalytic reaction is carried out at a pressure of about 1-100 atmospheric pressures. 8. The method of claim 1, wherein the zeolite beta catalyst is treated in a steam pretreatment step.