CN101190866B

CN101190866B - Arene alkyl transferring and dealkylation reaction method of low ethyl benzene by-product

Info

Publication number: CN101190866B
Application number: CN2006101185195A
Authority: CN
Inventors: 谢在库; 朱志荣; 祁晓岚; 孔德金; 左煜; 张惠明
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2006-11-21
Filing date: 2006-11-21
Publication date: 2011-08-17
Anticipated expiration: 2026-11-21
Also published as: CN101190866A

Abstract

The present invention relates to a transalkylation of aromatics and dealkylation method that produces low content of ethyl benzene by-product, and mainly solves the problem that reaction products have high content of the ethyl benzene by-product in the prior art, thus causing low selectivity to target product of dimethyl benzene among mixed carbon-eight products and no selectivity to dealkylation of side chains of arene alkylation. The present invention adopts the technical proposal of producing target product of dimethyl benzene through reaction in the fixed reaction bed by adopting carbon-nine and above heavy aromatics and methyl benzene as raw material or adopting carbon-nine and the heavy aromatics as raw material, adopting catalyst containing zeolite with SiO2/Al2O3 mole ratio of 12-70 by weight proportion, oxide that is selected from at least one of molybdenum, palladium or nickel, oxide that is selected from at least one of ferrum, bismuth, tin or platinum and oxide that is selected from at least one of magnesium or titanium, and in reaction conditions of weight space velocity of 1.0 to 3.5h<-1>, reaction temperature of 350 - 460 DEG C, reaction pressure of 1.5 to 3.5MPaand molecular proportion of hydrogen/hydrocarbon of 2.0 to 80, thereby properly solving the problem. The method can be used for industrial production of carbon-nine and above heavy aromatics or transalkylation of phenylmethane and dealkylation to reduce content of the ethyl benzene by-product and increase content of the dimethyl benzene product.

Description

The aromatic hydrocarbons transalkylation of low ethyl benzene by product and dealkylation method

Technical field

The present invention relates to a kind of aromatic hydrocarbons transalkylation and dealkylation method of low ethyl benzene by product, particularly about being raw material or being raw material with carbon nine and above heavy arene thereof separately with carbon nine and above heavy arene thereof and toluene, by transalkylation and dealkylation, thus the reaction method of ethylbenzene by-products content increasing production of xylol product in reduction side reaction and the product.

Background technology

P-Xylol in the dimethylbenzene is one of main basic organic of petrochemical industry, in numerous chemical production field such as chemical fibre, synthetic resins, agricultural chemicals, medicine, plastics purposes is widely arranged.For increasing production of xylol, utilize toluene disproportionation or toluene and carbon nine and above heavy aromatics (C thereof ₉ ⁺A) disproportionation and transalkylation reaction generate benzene and C ₈A reaches the purpose of effective volume increase p-Xylol by increasing production of xylol.

People are usually C9 aromatic (C ₉A), carbon ten and above heavy aromatics (C thereof ₁₀ ⁺A) be referred to as heavy aromatics.Petroleum Aromatics is mainly derived from the byproduct that light oil cracking is produced ethylene unit; The aromatic hydrocarbons that the refinery catalytic reforming is produced; The byproduct of toluene disproportionation and transalkylation unit.Along with increasing of heavy arene amount, the comprehensive utilization of heavy arene becomes the problem that people are concerned about, wherein C ₉The processing and utilization of A has sophisticated method, is widely used as the raw material of toluene disproportionation and transalkylation reaction, is used for making benzene and C ₈A.Aromatic Hydrocarbon United Plant of producing 22.5 ten thousand tons of p-Xylol per year according to estimates, because the difference of stock oil, the difference of the course of processing, the annual C that produces ₁₀ ⁺A is 1～30,000 ton, and this is a kind of resource of preciousness, and present Aromatic Hydrocarbon United Plant does not also have suitable processing and utilizes method to this.

Along with the development of catalyst technology, can adopt the carbon ten heavy arene (C that sneak into certain content in the reaction raw materials at present ₁₀A) method improves the yield of purpose product, pursues under high conversion, the high-speed deficiency that product yield is on the low side, but C in fact to remedy ₁₀Have only about 20～30% to be utilized among the A, and about 80～70% C ₁₀A discharges at the bottom of the heavy aromatics Tata.

As a kind of important research project of rationally utilizing the heavy arene resource, heavy arene is produced dimethylbenzene by transalkylation and dealkylation lighting highly selective and also more and more has been subjected to people's attention.Heavy aromatic hydrocarbon light is by the hydro-dealkylation reaction, finally generates benzene, toluene and dimethylbenzene.Yet because heavy arene mainly is to produce light aromatic hydrocarbons by pyrolysis method and catalytic dealkylation method at present, pyrolysis method takes off alkyl and causes the hydrogen consumption to increase, and the side chain alkyl-methyl of aromatic hydrocarbons, the alkyl that takes off of ethyl are not had selectivity, causes raw material toluene, C ₉ ⁺The major ingredient trimethylbenzene of A and ethyl methyl benzene and product dimethylbenzene demethylation are serious, the methyl conservation rate is low, dimethylbenzene selective is poor thereby make, more than cause raw material toluene, trimethylbenzene, ethyl methyl benzene are not utilized effectively, the yield of purpose product dimethylbenzene is lower, owing to optionally do not take off ethyl, make product C simultaneously ₈Ethyl-benzene level is higher among the A, gives mixed C ₈The further separating dimethyl benzene technology of A is brought difficulty, and these all make the technico-economical comparison of xylene production relatively poor, and commercialization is restricted.

In the public clear 51-29131 patent of spy, use MoO ₃-NiO/Al ₂O ₃(weight consists of 13%Mo, 5%Ni) is catalyzer, with C ₉A-C ₁₀A (benzene 0.81%, toluene 0.26%, C ₈A0.95%, C ₁₀A15.23%) be raw material, under 6MPa and 550 ℃ of reaction conditionss, during reaction product is formed by weight percentage for containing benzene 9.74%, toluene 30.27%, dimethylbenzene 32.33% and non-aromatics 0.16%.

USP5,942,651 disclose a kind of with benzene or toluene and C ₉ ⁺The method of the light aromatic hydrocarbons of A transalkylation production, this method becomes two beds with two kinds of catalyst loadings, perhaps be seated in the reactor of two polyphones, the described first kind of zeolite of this method mainly is selected from MCM-22, PSH-3, SSZ-25, ZSM-12 or β, second kind of zeolite is selected from ZSM-5, the amount of second kind of catalyzer accounts for 1～20% of catalyzer total amount, and best 10～15%.When reaction, raw material need be passed through first beds earlier, and the control weight space velocity is at 1.0～7.0 o'clock ^-1, be preferably at 2.5～4.5 o'clock ^-1, be 5.0～100.0 o'clock by the weight space velocity of second beds ^-1, be preferably at 15.0～35.0 o'clock ^-1, the purpose of this method is to make raw material pass through first catalyzer with slower speed, generates intermediates, then allowing these intermediates pass through second catalyzer with fast speeds, to generate more BTX.

Carbon nine and above heavy arene content thereof more only carry out transalkylation reaction by zeolite itself in raw material, the often very fast inactivation of catalyzer.United States Patent (USP) 4723048 discloses a kind of toluene and alkylaromatic hydrocarbon disproportionation/transalkylation catalyst, load Ni or Pd, Ag, Sn, Pt or Ge on mordenite.Mainly as hydrogenation metal, its activity is subjected to the control of Sn, Ge metal, to improve the performance of catalyzer for nickel or palladium in this patent.

In the above-mentioned document, include toluene aromatic hydrocarbons in the fresh feed of use, the yield of purpose product dimethylbenzene is lower when perhaps having only heavy arene in the reaction feed, owing to optionally do not take off ethyl, makes product C simultaneously ₈Ethyl-benzene level is higher among the A, gives mixed C ₈The further separating dimethyl benzene technology of A is brought difficulty, technico-economical comparison and unreasonable problem such as feasible, thus limit its industrializing implementation.

Because heavy arene mainly is to produce light aromatic hydrocarbons by pyrolysis method and catalytic dealkylation method at present, pyrolysis method takes off alkyl and causes the hydrogen consumption to increase, and the side chain alkyl-methyl of aromatic hydrocarbons, the alkyl that takes off of ethyl are not had selectivity; At present the bibliographical information catalyzer to the side chain alkyl-methyl of aromatic hydrocarbons, ethyl to take off the alkyl selectivity also lower, can not carry out high-level efficiency, highly selective takes off ethyl, cause ethylbenzene by-products content height in the reaction product, to mix in carbon eight products dimethylbenzene target product selectivity lower, bring difficulty to technology, simultaneously because to raw material toluene, C ₉ ⁺The major ingredient trimethylbenzene of A and ethyl methyl benzene and product dimethylbenzene demethylation are serious, thereby raw material toluene, trimethylbenzene, ethyl methyl benzene are not utilized effectively, and these all make the technico-economical comparison of xylene production relatively poor.

Summary of the invention

Technical problem to be solved by this invention is that ethylbenzene by-products content height causes that to mix in carbon eight products dimethylbenzene target product selectivity lower in the reaction product that exists in the prior art, to the not problem optionally of alkyl of taking off of aromatic hydrocarbons side chain alkyl, provide a kind of aromatic hydrocarbons transalkylation and dealkylation method of new low ethyl benzene by product.This method is used for being raw material or being raw material with carbon nine and above heavy arene thereof separately with carbon nine and above heavy arene thereof and toluene, when carrying out transalkylation and dealkylation, can realizes that high-level efficiency, highly selective take off ethyl, make product C ₈Ethyl-benzene level is lower among the A, has product dimethylbenzene selective height, mixed C ₈The further separating dimethyl benzene of A is easy, xylene loss is less, to greatest extent the characteristics of increasing production of xylol target product.

In order to solve the problems of the technologies described above, the technical solution used in the present invention is as follows: a kind of aromatic hydrocarbons transalkylation of low ethyl benzene by product and dealkylation method, being raw material or being reaction raw materials with carbon nine and above heavy arene thereof separately with carbon nine and above heavy arene thereof and toluene, is 1.0～3.5 hours at weight space velocity ^-1Temperature of reaction is 350～460 ℃, reaction pressure is 1.5～3.5MPa, hydrogen/hydrocarbon molecule is than under 2.0～8.0 reaction conditionss, raw material contacts with catalyzer, by transalkylation with take off the alkyl catalyzed reaction and generate the dimethylbenzene target product, the weight ratio of carbon nine and above heavy arene and toluene is 0.1～1: 0～0.9 in its reaction raw materials, and described catalyzer comprises following component in parts by weight:

1) SiO ₂/ Al ₂O ₃Mol ratio is 40～90 parts of 12～70 h-type zeolites;

2) be selected from 0.002～8 part of oxide compound at least a in molybdenum, palladium or the nickel;

3) 0.005～8 part of at least a oxide compound in chosen from Fe, bismuth, tin or the platinum;

4) be selected from 0.02～8 part of oxide compound at least a in magnesium or the titanium;

5) binding agent is 10～60 parts.

In the technique scheme, the weight ratio preferable range of carbon nine and above heavy arene and toluene is 0.3～0.8: 0.2～0.7 in the reaction raw materials.The preferable range of reaction conditions: the reaction weight space velocity is 1.5～2.5 hours ^-1, temperature of reaction is 360～440 ℃, and reaction pressure is 2.1～3.1MPa, and hydrogen/hydrocarbon molecule ratio is 3.0～6.0.In reaction raw materials carbon nine and the above heavy arene thereof preferred version for by weight percentage wherein indane be 1～10%, carbon ten and above aromatic hydrocarbons 2～20% thereof.The h-type zeolite preferred version is selected from least two kinds among β zeolite, mordenite or the ZSM-5; In parts by weight, being selected from oxide compound consumption preferable range at least a in molybdenum, palladium or the nickel is 0.1～6 part; At least a oxide compound preferable range is 0.05～5 part in chosen from Fe, bismuth, tin or the platinum; Being selected from oxide compound consumption preferable range at least a in magnesium or the titanium is 0.1～6 part; The binding agent preferred version is for being selected from aluminum oxide, silicon-dioxide or wilkinite.

The Preparation of catalysts method is through dipping or ion-exchange or mixing or mediate extrusion, after 400～570 ℃ of roastings make by h-type zeolite, aluminum oxide and employed metal-salt among the present invention.

Catalyzer of the present invention uses fixed-bed reactor to carry out reactivity worth and investigates.25 millimeters of reactor inside diameter φ, 1200 millimeters of length, stainless steel.Adopt electrically heated, temperature is controlled automatically.5 millimeters granulated glass spherees of reactor bottom filling φ are as upholder, filling catalyzer 20 grams in the reactor, and 5 millimeters granulated glass spherees of top filling φ are made for the usefulness of raw material preheating and vaporization.Fresh C in the raw material ₉ ⁺A and raw material toluene mix with hydrogen, from top to bottom by beds, transalkylation and/or dealkylation take place, and generate more rudimentary aromatic hydrocarbons such as dimethylbenzene, benzene, and alkane such as a small amount of methane, ethane, propane, butane.

Raw material C ₉ ⁺A derives from the petrochemical complex Aromatic Hydrocarbon United Plant, and testing data is calculated as follows.

Reaction method of the present invention, owing in catalysts, adopt and be selected from the β zeolite, at least two kinds of composite zeolites among mordenite or the ZSM-5 are as the catalytic activity main body, at least three kinds of complex metal oxidess have been added simultaneously as the catalytic activity auxiliary agent, this technology is applicable to carbon nine and above heavy arene thereof and toluene and is raw material or is raw material (wherein the ratio preferable range of carbon nine and above heavy arene and toluene is 0.8: 0.2～0.3: 0.7) with carbon nine and above heavy arene thereof separately, when carrying out transalkylation and dealkylation production dimethylbenzene target product, can realize high-level efficiency, highly selective takes off ethyl, makes product C ₈Ethyl-benzene level is lower among the A, has the high characteristics of product dimethylbenzene selective, has obtained better technical effect.

The invention will be further elaborated below by embodiment.

Embodiment

[embodiment 1]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 22 gram and the Na of molecular ratio 23 ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 45 gram and the Na of molecular ratio 24 ₂O content is less than the Al of 0.1% (weight) ₂O ₃42 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; Powder behind the dipping adds the dilute nitric acid solution of Bismuth trinitrate, magnesium nitrate, cerous nitrate again, fully mediates evenly, carries out extruded moulding, catalyst A is made in 500 ℃ of roastings.

[embodiment 2]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 36 gram and the Na of molecular ratio 22 ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 25 gram and the Na of molecular ratio 25 ₂O content is less than the Al of 0.1% (weight) ₂O ₃35 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; Powder behind the dipping adds a certain amount of dilute nitric acid solution, Bismuth trinitrate, nickelous nitrate, lanthanum nitrate, iron nitrate and Palladous chloride, fully mediates evenly, carries out extruded moulding, catalyst B is made in 500 ℃ of roastings.

[embodiment 3]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃The ammonium type mordenite of molecular ratio 22 and 12 gram Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 62 gram and the Na of molecular ratio 30 ₂O content is less than the Al of 0.1% (weight) ₂O ₃38 gram uniform mixing add a certain amount of dilute nitric acid solution, cobaltous acetate, chlorination four ammonia platinum, tin protochloride, nickelous nitrate and lanthanum nitrate then, fully mediate evenly, carry out extruded moulding, catalyzer C is made in 500 ℃ of roastings.

[embodiment 4]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 19 grams of molecular ratio 22, Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 52 gram and the Na of molecular ratio 22 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 11 gram and the Na of molecular ratio 48 ₂O content is less than the Al of 0.1% (weight) ₂O ₃40 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; The catalyzer D that powder behind the dipping adds a certain amount of dilute nitric acid solution, iron nitrate, Bismuth trinitrate and lanthanum nitrate, carries out extruded moulding, different metal content is made in 500 ℃ of roastings.

[embodiment 5]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 21 grams of molecular ratio 23, Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 40 gram and the Na of molecular ratio 25 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 20 gram and the Na of molecular ratio 28 ₂O content is less than the Al of 0.1% (weight) ₂O ₃38 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; Add a certain amount of dilute nitric acid solution, nickelous nitrate, Bismuth trinitrate, cerous nitrate, titanium tetrachloride then, fully mediate evenly, carry out the catalyzer E that extruded moulding, 500 ℃ of roastings are made different metal content.

[embodiment 6]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 18 grams of molecular ratio 24, Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 49 gram and the Na of molecular ratio 23 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 16 gram and the Na of molecular ratio 32 ₂O content is less than the acid-treated wilkinite 24 gram uniform mixing of 0.1% (weight), add a certain amount of dilute nitric acid solution, nickelous nitrate, Bismuth trinitrate, cerous nitrate, iron nitrate and magnesium nitrate then, fully mediate evenly, carry out extruded moulding, 500 ℃ of roastings, make the catalyzer F of different metal content.

[embodiment 7]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 11 grams of molecular ratio 22, Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 56 gram and the Na of molecular ratio 22 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 21 gram and the Na of molecular ratio 27 ₂O content is less than the Al of 0.1% (weight) ₂O ₃23 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; Add a certain amount of dilute nitric acid solution, titanium tetrachloride, Bismuth trinitrate and lanthanum nitrate hexahydrate then, fully mediate evenly, carry out extruded moulding, catalyzer G is made in 500 ℃ of roastings.

[embodiment 8]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 6 grams of molecular ratio 16, Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 26 gram and the Na of molecular ratio 24 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 31 gram and the Na of molecular ratio 34 ₂O content is less than the Al of 0.1% (weight) ₂O ₃53 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; Add a certain amount of dilute nitric acid solution, chlorination four ammonia platinum, tin protochloride, Palladous nitrate and lanthanum nitrate hexahydrate solution then, fully mediate evenly, carry out extruded moulding, catalyzer H is made in 500 ℃ of roastings.

[embodiment 9]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 34 gram and the Na of molecular ratio 23 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 21 gram and the Na of molecular ratio 72 ₂O content is less than the Al of 0.1% (weight) ₂O ₃60 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; Add a certain amount of dilute nitric acid solution, Bismuth trinitrate and cerous nitrate solution then, fully mediate evenly, carry out extruded moulding, 500 ℃ of roastings, make catalyst I.

[embodiment 10]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 45 gram and the Na of molecular ratio 20 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 23 gram and the Na of molecular ratio 26 ₂O content is less than the Al of 0.1% (weight) ₂O ₃31 gram uniform mixing add a certain amount of dilute nitric acid solution, nickelous nitrate, cerous nitrate, iron nitrate, magnesium nitrate and bismuth nitrate solution then, fully mediate evenly, carry out extruded moulding, catalyzer J is made in 500 ℃ of roastings.

[embodiment 11]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type mordenite 50 gram and the Na of molecular ratio 24 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 15 gram and the Na of molecular ratio 46 ₂O content (contains SiO by weight percentage, less than the silicon sol of 0.1% (weight) ₂30%) 61 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; After the oven dry of powder behind the dipping, fully mediate evenly with the dilute nitric acid solution of Palladous nitrate, Bismuth trinitrate, tin protochloride and titanium tetrachloride again, carry out extruded moulding, catalyzer K is made in 500 ℃ of roastings.

[embodiment 12]

Adopt Na ₂O content is less than 0.1% (weight), SiO ₂/ Al ₂O ₃Ammonium type β zeolite 47 gram and the Na of molecular ratio 25 ₂O content is less than 0.10% (weight), SiO ₂/ Al ₂O ₃Ammonium type ZSM-5 zeolite 13 gram and the Na of molecular ratio 38 ₂O content is less than the Al of 0.1% (weight) ₂O ₃31 gram uniform mixing are made into the aqueous solution with ammonium molybdate then and flood; Add a certain amount of bismuth nitrate solution then and carry out incipient impregnation, fully mediate with the dilute nitric acid solution of lanthanum nitrate again after the oven dry, carry out extruded moulding, 500 ℃ of roastings, make the catalyzer L that contains three kinds of metals.

The catalyzer that makes with embodiment 1～12 carries out transalkylation and the investigation of dealkylation reactive behavior on the fixed bed reaction evaluating apparatus.Loaded catalyst is 40 grams, and weight space velocity is 2.5 hours ^-1, temperature of reaction is 390 ℃, and reaction pressure is 3.0MPa, and hydrogen/hydrocarbon molecule is than 4.0, and raw material weight percentage composition toluene is 45.5%, C ₉ ⁺A is 54.5% (C wherein ₁₀ ⁺A is 6.2, indane 0.9), C in the raw material ₉The A weight percent consists of: propyl benzene 3.5%, first and second benzene 35.1%, trimethylbenzene 63.4%, C ₁₀ ⁺The A weight percent consists of: diethylbenzene 2.3%, dimethyl ethylbenzene 27.0%, methyl propyl benzene 2.3%, durene 27.8%, methylnaphthalene 14.5%, dimethylnaphthalene 11.2%, other 12.9%, the concrete evaluation result such as the table 1 of catalyzer.

The reaction evaluating result of the catalyzer that table 1 is made (unit: weight is in oxide compound)

Embodiment

Catalyzer

Zeolite

Binding agent

M ₁ /％

M ₂ /％

M ₃ /％

Ethyl-benzene level/%

Ethyl removes ratio/%

C ₈Dimethylbenzene selective/% among the A

1

A

β/MOR

Aluminum oxide

Mo/3.5

Bi/2.2

Ce/2.4

0.15

93.8

99.6

2

B

β/MOR

Aluminum oxide

Mo/1.0 Ni/1.7 Pd/0.2

Bi/0.9 Fe/1.5

La/1.8

0.26

90.2

99.2

3

C

β/MOR

Aluminum oxide

Ni/1.2

Sn/1.5 Pt/0.1

La/3.7

0.13

94.2

99.6

4

D

β/MOR/ZSM-5

Aluminum oxide

Mo/3.3

Bi/1.6 Fe/0.2

La/4.5

0.09

95.1

99.7

5

E

β/MOR/ZSM-5

Aluminum oxide

Mo/2.4 Ni/1.0

Bi/1.8

Ti/1.5 Ce/1.6

0.23

90.5

99.3

6

F

β/MOR/ZSM-5

Wilkinite

Ni/1.6

Bi/1.5 Fe/3.3

Mg/0.3 Ce/4.2

0.18

90.9

99.4

7

G

β/MOR/ZSM-5

Aluminum oxide

Mo/4.1

Bi/2.9

La/2.1 Ti/0.2

0.19

91.3

99.4

8

H

β/MOR/ZSM-5

Aluminum oxide

Mo/2.8 Pd/0.2

Sn/1.9 Pt/0.2

La/3.2

0.14

94.2

99.6

9

I

MOR/ZSM-5

Aluminum oxide

Mo/1.2

Bi/2.9

Ce/1.8

0.17

92.2

99.5

10

J

β/ZSM-5

Aluminum oxide

Ni/1.2

Bi/2.5 Fe/0.1

Ce/1.8 Mg/2.2

0.16

92.8

99.5

11

K

MOR/ZSM-5

Silicon-dioxide

Mo/2.3 Pd/0.1

Bi/2.0 Sn/1.5

Ti/2.0

0.19

91.5

99.4

12

L

β/ZSM-5

Aluminum oxide

Mo/4.0

Bi/2.1

La/3.2

0.13

94.1

99.6

^*MOR is a mordenite.

[embodiment 13～17]

Catalyzer D with embodiment 4 makes carries out transalkylation and the investigation of dealkylation performance at fixed-bed reactor, and the evaluation result under the differential responses condition is as shown in table 2.Raw material is formed identical with the raw material that is used for embodiment 1～12.

Table 2 transalkylation and dealkylation result

Embodiment	Reaction pressure, MPa	Weight space velocity, hour ^-1	Temperature of reaction, ℃	Hydrogen hydrocarbon molecule ratio	Ethyl-benzene level/%	Ethyl removes ratio/%	C ₈Dimethylbenzene selective/% among the A
								13	1.4	1.2	350	6	0.16	93.8	99.5
14	2.2	1.7	390	3	0.22	91.2	99.3
								15	1.8	1.5	370	5	0.19	92.6	99.4
16	2.7	2.2	410	4	0.10	95.0	99.7
								17	3.2	3.1	430	2	0.26	90.1	99.2

[embodiment 18～20]

Catalyzer D with embodiment 4 makes carries out transalkylation and the investigation of dealkylation performance at fixed-bed reactor, and weight space velocity is 2.5 hours ^-1, 390 ℃ of temperature of reaction, reaction pressure 3.0MPa, hydrogen/hydrocarbon molecule are than 4.0, and raw material is formed as shown in table 3.Evaluation result is as shown in table 4.

Table 3 raw material is formed weight %

Numbering	T	C ₉	IND	C ₁₀
					1	28.1	51.4	2.2	18.2
2	47.7	43.3	1.2	7.8
					3	64.3	31.9	0.6	3.2

^*T is a toluene, and IND is an indane.

Table 4 transalkylation and dealkylation result

Embodiment	Raw material	Ethyl-benzene level/%	Ethyl removes ratio/%	C ₈Dimethylbenzene selective/% among the A
					18	1	0.24	91.1	99.3
19	2	0.19	93.5	99.4
					20	3	0.11	95.2	99.7

Evaluation result shows, the present invention makes is selected from the β zeolite, at least two kinds of zeolites among mordenite or the ZSM-5 and at least three kinds are selected from molybdenum, nickel, iron, bismuth, tin, platinum, palladium, cerium, magnesium, the catalyzer that titanium or lanthanum-oxides are made, this catalyzer is by adopting the β zeolite, at least two kinds of composite zeolites among mordenite or the ZSM-5 are as the catalytic activity main body, added the method for composition metal simultaneously as the catalytic activity auxiliary agent, can regulate the control catalytic performance effectively, be raw material with carbon nine and above heavy arene thereof and toluene or be under the condition of raw material with carbon nine and above heavy arene thereof separately, can be in wide reaction raw materials under the proportional range and reaction conditions of carbon nine and above heavy arene and toluene, by transalkylation and dealkylation, and realization high-level efficiency, highly selective takes off ethyl, makes product C ₈Ethyl-benzene level is lower among the A, suppresses the demethylation side reaction simultaneously, thereby has high target product dimethylbenzene selective.

Claims

1. the aromatic hydrocarbons transalkylation of a low ethyl benzene by product and dealkylation method are raw material or are reaction raw materials with carbon nine and above heavy arene thereof separately with carbon nine and above heavy arene thereof and toluene, are 1.0～3.5 hours at weight space velocity ^-1Temperature of reaction is 350～460 ℃, reaction pressure is 1.5～3.5MPa, hydrogen/hydrocarbon molecule is than under 2.0～8.0 reaction conditionss, raw material contacts with catalyzer, by transalkylation with take off the alkyl catalyzed reaction and generate the dimethylbenzene target product, the weight ratio of carbon nine and above heavy arene and toluene is 0.1～1: 0～0.9 in its reaction raw materials, and described catalyzer comprises following component in parts by weight:

1) SiO ₂/ A1 ₂O ₃Mol ratio is 40～90 parts of 12～70 h-type zeolites;

5) binding agent is 10～60 parts.

2. according to the aromatic hydrocarbons transalkylation and the dealkylation method of the described low ethyl benzene by product of claim 1, it is characterized in that the weight ratio of carbon nine in the reaction raw materials and above heavy arene and toluene is 0.3～0.8: 0.2～0.7.

3. according to the aromatic hydrocarbons transalkylation and the dealkylation method of the described low ethyl benzene by product of claim 1, it is characterized in that weight space velocity is 1.5～2.5 hours ^-1, temperature of reaction is 360～440 ℃, and reaction pressure is 2.1～3.1MPa, and hydrogen/hydrocarbon molecule ratio is 3.0～6.0.

4. according to the aromatic hydrocarbons transalkylation and the dealkylation method of the described low ethyl benzene by product of claim 1, it is characterized in that h-type zeolite is selected from least two kinds among β zeolite, mordenite or the ZSM-5.

5. according to the aromatic hydrocarbons transalkylation and the dealkylation method of the described low ethyl benzene by product of claim 1, it is characterized in that being selected from oxide compound consumption at least a in molybdenum, palladium or the nickel in parts by weight is 0.1～6 part.

6. according to the aromatic hydrocarbons transalkylation and the dealkylation method of the described low ethyl benzene by product of claim 1, it is characterized in that in oxide compound consumption at least a in parts by weight chosen from Fe, bismuth, tin or the platinum be 0.05～5 part.

7. according to the aromatic hydrocarbons transalkylation and the dealkylation method of the described low ethyl benzene by product of claim 1, it is characterized in that being selected from oxide compound consumption at least a in magnesium or the titanium in parts by weight is 0.1～6 part.

8. according to the aromatic hydrocarbons transalkylation and the dealkylation method of the described low ethyl benzene by product of claim 1, it is characterized in that binding agent is selected from aluminum oxide, silicon-dioxide or wilkinite.

9. according to the aromatic hydrocarbons transalkylation and the dealkylation method of the described low ethyl benzene by product of claim 1, it is characterized in that in carbon nine and the above heavy arene thereof by weight the percentage meter wherein indane be 1～10%, carbon ten and above aromatic hydrocarbons 2～20% thereof.