JPS5939836A - Preparation of 1,2,4,5-tetraalkylbenzene - Google Patents

Abstract

PURPOSE:To obtain selectively the titled substance useful as a raw material for heat-resistant polyimide resins, etc., by alkylating pseudocumene with methanol, etc. in the presence of a hydrogen type crystalline aluminosilicate having a specific crystal structure as a catalyst. CONSTITUTION:Pseudocumene is alkylated with methanol, ethanol, propanol, ethylene or propylene, etc. in the presence of a crystalline aluminosilicate, e.g. ZSM-5 zeolite, having a main cavity consisting of a 10-membered oxygen ring, >=5Angstrom effective pore diameter and hydrogen in at least part of cations capable of ion exchange as a catalyst to give the titled substance. The molar ratio between the silica and alumina in the above-mentioned catalyst is 10-50, and the reaction is carried out under the following conditions: 200-300 deg.C reaction temperature and 20-80g.hr/mol ratio between the weight of the catalyst and the feed rate of the raw mateial. EFFECT:The above-mentioned catalyst has slight reduction in the activity with time and exhibits remarkable stable catalytic performance.

Description

DETAILED DESCRIPTION OF THE INVENTION Rubenzene) is alkylated to produce 1, 2, 4. 5-
The present invention relates to a method for producing tetraalkylbenzene. More specifically, the present invention relates to a method for selectively producing 1,2,4,5-tetraalkylbenzene by alkylating pseudocumene using a crystalline aluminosilicate as a catalyst.

Pyromellit rW (1,2,4,5-benzenetetracarboxylic acid) obtained by oxidizing 1,2,4.5-tetraalkylbenzene or its anhydride, anhydrous pyromellit, is a heat-resistant plasticizer or a heat-resistant Demand is increasing as a raw material for polyimide resin.

Therefore, the development of an industrially advantageous method for producing 1,2,4,5-tetraalkylbenzene, which is the raw material for the production of 1,2,4,5-tetraalkylbenzene, is therefore expected.

1, 2° obtained by alkylating pseudocumene 4.
5-tetraalkylbenzene is 5-alkyl 1, 2.
4. -) IJ methylbenzene, which includes durene (1,2,4,5-tetramethylbenzene).

5-isopropyl pseudocumene (5-isopropyl 1
．． 2.4. -) Limethylbenzene), etc.

Known methods for producing durene include a method of directly concentrating and crystallizing durene from catalytically reformed oil, a method of disproportioning trimethylbenzene, and a method of methylating pseudocumene.

The method of directly concentrating and crystallizing and separating Deerene from catalytic reformed oil requires a large amount of cost and is not economical because the concentration of Durene contained in the reformed oil is low.

Examples of methods for disproportionating trimethylbenzene include:
As shown in Japanese Patent Publication No. 50-13778 or Journal of the Japan Petroleum Institute, Vol. 17, No. 12, pp. 1022-1027 (1974), solid acids such as silica auto-alumina, mordenite, or faujasite type zeolite are used as catalysts. Although methods using catalysts are known, these catalysts have problems such as low disproportionation activity and large changes over time.

Regarding the method of producing durene by methylating pseudocumene, a liquid phase method using a Friedel-Crafts type catalyst such as aluminum chloride is known, but this method requires a large number of catalysts and requires equipment. It has disadvantages such as severe corrosion. Furthermore, regarding the method of producing durene by methylating pseudocumene with methanol in the gas phase, for example, Japanese Patent Publication No. 41-20341
No. or Journal of the Japan Petroleum Institute, Vol. 17, No. 12, pp. 1028-1
As shown on page 032 (1974), a method using silica-alumina or Y-type zeolite ion-exchanged to hydrogen type as a catalyst is known. However, this method has some drawbacks, such as a low selectivity for the target durene and a severe decrease in activity due to coking.
It was not necessarily practical for industrial use.

The method for producing 5-isopropyl pseudocumene is described, for example, in the Journal of Japan Petroleum Society, Vol. 15, No. 3, pp. 585-38.
As shown on page 8 (1972), a method is known in which pseudocumene is propylated with propylene in a liquid phase using a hydrogen-formed Y-type zeolite as a catalyst. However, even in this method, the activity of the catalyst and 1.2.
The selectivity to 4,5-tetraalkylbenzene was low and was not industrially satisfactory.

Considering these circumstances, the present inventors alkylated pseudocumene with an alcohol or an olefin to obtain 1.
We have conducted extensive research on a method for selectively producing 2.4.5-tetraalkylbenzene.

As a result, a hydrogen-type crystalline aluminosilicate with a specific crystal structure exhibits extremely high selectivity and activity for this reaction, and has little activity loss over time.
The present invention was achieved by discovering that this catalyst exhibits extremely stable catalytic performance.

That is, the gist of the present invention is that when pseudocumene is alkylated, the main cavity is composed of a 10-membered oxygen group.
, using as a catalyst a crystalline aluminosilicate having an effective pore diameter of 5^ or more and at least a part of its exchangeable cations being hydrogen ions;
2.4. A method for selectively producing 5-tetraalkylbenzene.゛According to the method of the present invention, the production of 1.2.3.4- or 1.2.3.5-tetraalkylbenzene other than 1,2,4.5-tetraalkylbenzene is suppressed, and therefore, tetraalkylbenzene 1.2.4 inside
．． In addition to achieving a high selectivity for 5-tetraalkylbenzene, the raw material pseudocumene is mesitylene (1,45-trimethylbenzene) or hemimelitene (1,2,3-
Since the isomerization to (trimethylbenzene) is suppressed to a significantly lower level than in the above alkylation reaction, efficient alkylation of pseudocumene to 1,2,4,5-tetraalkylbenzene becomes possible.

Furthermore, compared to the conventionally known method using Y-type zeolite as a catalyst, there is almost no reduction in catalyst activity due to coking, etc., and therefore there is an advantage that complicated regeneration treatment of the catalyst is not required. Therefore, the present invention provides an industrially extremely useful method.

Below, non-invention will be explained in detail.

In the method of the present invention, a crystalline aluminosilicate having a main cavity consisting of a 10-membered oxygen group and having an effective pore diameter of 5 or more is used as a catalyst. -5 type zeolite is mentioned.

ZBM-5 type zeolite is a typical zeolite having a 10-member oxygen-filled main cavity, and is described in Japanese Patent Publication No. 46-10064, U.S. Patent No. 790,471, etc. ZSM-5, which is
ZSM- described in JP-A-47-25.097
8. ZSM described in Special Publication No. 53-25280
-11, ZSM-21 described in U.S. Pat.

In addition, ferrierite and the like are examples of zeolites having a main cavity of a 10-membered oxygen ring. Ferrierite has a structure similar to that of the Journal of Catalysis (Jou
rn++1 of C! analysis) Volume 35 2
56 to 272 (1974), and the manufacturing method is described in JP-A-50-127898 or JP-A-55-854.
It is written in No. 15 etc.

The effective pore diameter of about 10 oxygen members, which is the main cavity of ferrierite, is about 5X.

Generally, the crystal structure of zeolite, which is a crystalline aluminosilicate, is X1vi! Determined by diffraction techniques and distinguished from other zeolites. Nature
ure) Vol. 272, pp. 437-438 (1978) shows the crystal structure of ZSM-5 zeolite, which is suitably used as a typical catalyst component in the method of the present invention.

ZSM-5 belongs to the orthorhombic system, and a=2α1. b=19.
9. It has a lattice constant of c=1141.

Then, along the a-axis direction, there is a zigzag circular pore passage with a diameter of about a5g, and along the b-axis direction that intersects it, there is a straight elliptical pore passage with a major diameter of s, a x and a minor diameter of 5.2g. have. The entrances of the main cavities forming such a three-dimensional pore structure are each composed of a 1G-membered oxygen ring. The effective pore size of Z SM -5 is approximately 6X.

The powder Xa diffraction pattern of ZSM-5 zeolite is described in the above-mentioned Japanese Patent Publication No. 46-10064, and is as shown in Table 1. That is, ZBM-5 is 2θ=aO degrees, 90 degrees.

It is characterized by strong X-ray diffraction peaks seen around 252 degrees and 24.0 degrees. Note that here 2θ is 0u
The diffraction angle for case b may vary to some extent depending on measurement conditions, etc.

Journal Kenop Physical Chemistry (
Journal of Phyaica'l C! hs
mistry) Vol. 83, No. 21, pp. 2777-2781
(1979) describes the effects of cation exchange, calcination, etc. on the X-ray diffraction pattern of ZSM-5 zeolite.

152 # &7 z
311294 l 50 l
I 64230.1 t
5 ro l 5
The method for synthesizing 13ZSM-5 type zeolite is as follows:
"t to C6 tetraalkylammonium.

Hydrothermal synthesis methods using other amines are known.

That is, ZBM-5 is tetrapropylammo:t)A
, ZSM-8 is te)laethylammonium, ZSM-1
Methods using tetrabutylammonium for 1, 2-hydroxyethyltrimethylammonium for zsM-21, and pyrrolidine for zSM-5 are generally known. In addition, there are several methods for synthesizing ZSM-5 type zeolite other than these. Are known.

The crystalline aluminosilicate used as a catalyst in the method of the present invention can be synthesized by any of these methods, and its use in the present invention is not limited by the method of preparation.

As an example of the synthesis method of 28M-5 type zeolite, ZSM-
The synthesis of 5 zeolite is as follows.

That is, ZSM-5 uses colloidal silica or water glass as the silica source, sodium aluminate or aluminum sulfate as the alumina source, and sodium hydroxide as the sodium source.

Tetrapropylammonium bromide or tetrapropylammonium hydroxide is used as tetrapropylammonium, and the aqueous solution is expressed in molar ratio to have the following composition: OH-/sio, = α07~1.0R4N+, /(
R, N" + Na') = 0.2 to 0.95 (
However, R is a propyl group. ) H,010H-=10-300 SiO□/ht,o,=s-100 Synthesized by heating with a knife at a temperature of about 90°C to 200°C for about 1 hour to 8 days. A more preferable temperature range is about 1
00 to 175℃, and the heating time at that temperature is about 12
time to 8 days.

In this way, ZSM-5 zeolite having the following composition expressed in molar ratio of oxides is obtained.

0.9±n2M20@Aj, 03-5~1oosio,
@0-40H,O (here, M is a cation of valence n). In the state synthesized in this manner, tetrapropylammonium is contained in the zeolite as a cation instead of sodium. Therefore this air width is about 5
By firing at a temperature of 00°C to 600°C, some of the ion-exchangeable cations of the zeolite can be converted into hydrogen ions.

In the crystalline aluminosilicate used in the method of the present invention, at least some of the ion-exchangeable cations must be hydrogen ions. For this reason, it can be made into a hydrogen form by a conventionally known ion exchange method, for example, by ion exchange using an ammonium salt such as ammonium chloride or ammonium sulfate, followed by calcination, or by ion exchange using hydrochloric acid or the like. Further, if necessary, the crystalline aluminosilicate may be ion-exchanged with alkali metal ions by a known ion exchange method.

Ion exchange with alkaline earth metal ions or rare earth element ions is also possible. and at least about 3D% of the ion-exchangeable cations of the crystalline aluminosilicate used as a catalyst in the process of the invention.
In particular, it is preferable that about 70% or more of the hydrogen ions are hydrogen ions.

The silica/alumina ratio of the crystalline aluminosilicate used as a catalyst in the method of the present invention can be varied over a wide range, but is usually in the range of 5 to 100, and particularly 5 to 30 in view of high activity at low temperatures. Low silica/alumina ratios in the range are preferred.

Hereinafter, a method of implementing the present invention will be specifically explained.

In the alkylation reaction of sinidocumene of the present invention, the crystalline pluminosilicate is usually used as a molded product. There are no particular restrictions on the molding method, but examples include extrusion molding, compression molding, rolling granulation, spray drying granulation,
It can be molded by other methods. At this time, if necessary, silica, alumina, silica-alumina, clay, titanium oxide, zirconia, activated clay, etc. can be added to improve the mechanical strength and other properties of the molded body. Further, the ion exchange treatment may be performed at any stage before or after molding the zeolite. The molded body thus obtained is usually calcined at a temperature of about 5006C to 600C and then used as a catalyst.

The form of the reaction can be either gas phase or liquid phase, and the reaction method can also be the conventionally known fixed bed flow reaction method,
Any method such as a fluidized bed method or a liquid phase pressurized stirring method can be used.

The reaction temperature varies depending on the reaction method and other factors, but is usually about 50
℃ to 400℃, preferably in the range of about 100℃ to 500℃. The reaction pressure also varies depending on the reaction method 2, form, etc., but it does not need to be particularly high pressure, and may be in the range of normal pressure to about 20 atm, usually normal pressure to about 10 atm.

In the method of the present invention, lower alcohols such as methanol, ethanol, propatool, and lower olefins such as ethylene and propylene can be used as alkylating agents. The molar ratio of the alkylating agent to the raw material pseudocumene may be about a5 or more, but is preferably in the range of about 1-5. Furthermore, methanol is particularly preferred as the alkylating agent. The raw material pseudocumene does not need to be particularly pure, even if it contains a small amount of trimethylbenzenes such as 1.45-) rimetherbenzene or 1.2.3-) limethylbenzene, tetramethylbenzenes, etc. There is no problem.

The method of the invention also uses nitrogen, argon,
Carbon dioxide, etc. can be used, as well as hydrogen or methane, ethane, propane.

The reaction can be suitably carried out in the coexistence of lower paraffins such as butane. It is not preferable that the molar ratio of these coexisting gases to the raw material is too large, and is usually about 5 to 3.
A range of 0 is appropriate.

Contact time W/F (unit: j'-hr/mole,
Here, W is the catalyst type if, F is the raw material supply rate mole/h
r) varies depending on the reaction temperature and other conditions, but in order to obtain a high conversion rate, it is preferably in the range of about 10 to 200, particularly preferably in the range of about 20 to 100.

The first feature of the present invention is that the selectivity from sinidocumene to tetraalkylbenzene is still high. This is 1.45- or 1. This means that there are fewer side reactions such as isomerization reaction to λ3-trimethylbenzene, disproportionation reaction to produce xylene and tetramethylbenzene, or peralkylation reaction to pentaalkylbenzene.

Therefore, pseudocumene can be efficiently converted to tetraalkylbenzene.

The second feature is that 1.2.4 in tetraalkylbenzene
The selectivity of 5-tetraalkylbenzene is extremely high. This has not been achieved with conventional catalyst systems, and is one of the major features of the method of the present invention.

Thirdly, compared to conventional catalysts, the catalyst of the present invention has a good catalyst life with a negligible decrease in activity. This is of great industrial importance and is an advantage of the method of the invention.

Hereinafter, the present invention will be described in more detail with reference to Examples, but the present invention is not limited thereto.

Example 1 Zsy-s zeolite was synthesized according to the method described in US Pat. No. 79,471.

That is, 148F of silica gel was dissolved in 1700ml of a 2N tetrapropylammonium hydroxide aqueous solution, and 12.8F of sodium aluminate was dissolved in an aqueous solution of 52.
0g/ was added.

This mixture was heated and stirred at 160° C. for 5 days in a 2 t autoclave. After cooling to room temperature, the obtained solid crystals were filtered, washed, and dried.

As a result of X-ray diffraction measurement of this product, the X-ray diffraction pattern was consistent with Table 1. Further, as a result of elemental analysis, it had the following composition.

0.54 R,O-α67 NatOn i@O
, -4a2 8i01 @ 7.2H, 0 (here R
is tetrapropylammonium. ) The crystals were calcined in air at 540°C for 3 days, and then ion-exchanged in a 2N aqueous hydrochloric acid solution at 90°C for 5 hours. Then, after washing with water and drying,
It was fired again in air at 540°C for 3 hours. Elemental analysis of this product revealed that it had the following composition.

α03NalCDi203 @ 47.7810. a&
7H,0 to this crystal powder 810. Silica sol was added to give a weight of 20% by weight, and after drying, 5% by weight of graphite was added and compression molded to a size of 5 mm x 5 mm. The obtained molded body was fired in air at 500° C. for 5 hours to obtain a catalyst.

The reaction was carried out using a fixed bed flow reactor.

That is, catalyst 10? was filled into a reaction tube, and the reaction was carried out while supplying pseudocumene and methanol using a microfeeder using hydrogen as a carrier gas. The reaction products were collected at regular intervals and analyzed by gas chromatography.

The molar ratio of pseudocumene:methanol:hydrogen was 1:1:
14, and the reaction was carried out under the conditions of w/y: 402·hr/mol 1θ9 and reaction temperature: 300° C. The results are shown in Table 2. There was no change in the reaction over time, and constant performance was exhibited even 6 hours after the start of the reaction.

Example 2 A reaction was carried out in the same manner as in Example 1 except that the same catalyst as in Example 1 was used and nitrogen was used instead of hydrogen in Example 1. The results were as shown in the second ffK.

Examples 3 to 10 ZSM-5 zeolites with different silica/alumina ratios were synthesized in the same manner as in Example 1.

As a result of powder xa diffraction measurement, the X-ray diffraction pattern matched that shown in Table 1. The crystals were calcined at 540°C for 3 hours, and then ion-exchanged in a 2N aqueous hydrochloric acid solution at 90°C for 5 hours. After washing with water and drying, it was fired again in air at 540°C for 5 hours. As a result of elemental analysis, this hydrogen type Z8M-5 zeolite had the following composition.

0.02 Na20-Aj, O,*24.38iQ
, -6,4HIO was molded and fired in the same manner as in Example 1 to obtain a catalyst.

When this was used to carry out a reaction in the same manner as in Example 1, the results shown in Table 2 were obtained.

Comparative Examples 1 to 3 For comparison, Table 3 shows the results using commercially available mordenite in hydrogen form as a catalyst instead of ZSM-5 zeolite. The mordenite had a silica/alumina ratio of about 10.

Reaction method 9 conditions etc. were the same as in Example 1.

Comparative Example 4 Table 6 shows the results using Y-type zeolite in hydrogen form as a catalyst. Reaction method 1 Conditions, etc. are indicated as implementation procedure l Amendment 1 item f'l: 1982 Patent Application No. 147781 2 Title of invention 1, 2.4. Process for producing 5-tetraalkylbenzene 6
Relationship with the case of the person making the amendment Patent applicant address 4560 Oaza Tomita, Shinnanyo City, Yamaro Prefecture 746 Phone number (585) 3311 4 Date of amendment order Voluntary amendment 6 Detailed description of the invention to be amended Contents of 7 amendments (1) “5 days” in the bottom 5 lines of page 19 of the specification was corrected to “3 hours”.

Written amendment to the above procedure August 30, 1981 Kazuo Wakasugi, Commissioner of the Japan Patent Office Indication of Item V1 1982 Patent Application No. 147781 2 Title of Invention 1, 2.4.5-Method for producing tetraalkylbenzene Person making the amendment 4 Date of the amendment order Voluntary amendment 6 Specification to be amended, scope of claims 9 Detailed description of the invention column 7 Contents of the amendment + 1) Amend the scope of the claim as a separate sheet.

(2) 6 lines per page 9 of the specification "Belongs to the orthorhombic system" was deleted.

(3) Table 1, page 11, row 4 in the rightmost column [h kl
Corrected J to "hkl".

(Xun, page 15, line 7 Change "5-30" to "10-50" by 1.

(6) Page 16, line 10 Corrected "100℃~300" to "200℃~30o".

(6)　Page 16, bottom 1 line Corrected "about 1-5" to "about 1 a5-6".

(7) Same page 17, line 13 Corrected "5-30" to "0-20".

(8) Same page 17 bottom 3 lines 8 Attached documents 1 copy (1) Pseudocumene is alkylated 1 and 1.2.
4. When producing 5-tetraalkylbenzene, it has a main cavity consisting of 10-membered oxygen atoms, has an effective pore diameter of 5X or more, and at least some of the ion-exchangeable cations are hydrogen ions. Crystalline aluminosilicate If
1, 2.4.5 Characterized by use as a catalyst
- A method for producing tetraalkylbenzene.

(2) Fluid cumene with methanol and ethanol.

The method according to claim 1, wherein the alkylation is carried out with one or more members selected from the group consisting of propatool, ethylene, and propylene.

(3) Crystalline aluminosilicate is X shown in Table 1
3. The method of claim 1 or 2, wherein the Z'5M-5 zeolite is characterized by a line diffraction pattern.

(4) The method according to any one of claims 1 to 3, wherein the crystalline aluminosilicate has a silica/alumina molar ratio in the range of 10 to 50.

(5) Reaction temperature 200°C to 300°C, catalyst weight/raw material supply rate = 20 to 809-hr/mole.

5. The method according to any one of claims 1 to 4, characterized in that the pseudocumene is produced under conditions of a methanol/pseudocumene molar ratio of 0.5 to 3 and a hydrogen/pseudocumene molar ratio of 0 to 20.

Claims (5)

[Claims] (1) 1.2.4 by alkylating pseudocumene
．． When producing 5-tetraalkylbenzene, a crystalline alumina having a main cavity consisting of a 10-membered oxygen group, an effective pore diameter of 5X or more, and at least a part of the ion-exchangeable cations are hydrogen ions is used. 1, 2.4.5- characterized in that a silicate is used as a catalyst
Method for producing tetraalkylbenzene. (2) Methanol and ethanol for pseudocumene. The method according to claim 1, wherein the alkylation is carried out with one or more selected from the group of propatool, ethylene, and propylene. (3) Crystalline aluminosilicate is X shown in Table 1
3. The method of claim 1 or 2, wherein the zeolite is a 28M-5 zeolite characterized by a line diffraction pattern. (4) The method according to any one of items 1 to 3, wherein the silica/alumina molar ratio of the crystalline aluminosilicate is in the range of 5 to 30. (5) Reaction temperature 200°C to 300°C, catalyst type t/raw material supply rate = 20 to 80? hr/mole. Methanol/pseudocumene molar ratio α5~3, hydrogen/
5. The method according to any one of claims 1 to 4, characterized in that pseudocumene is used at a molar ratio of 0 to 2 degrees.