CN101992082B - Catalyst for toluene methanol side-chain alkylation reaction and preparation method thereof - Google Patents

Abstract

The invention relates to a catalyst for preparing phenylethane and cinnamene through toluene methanol side-chain alkylation reaction and a preparation method thereof, which mainly solve the problems of low toluene conversion rate and lower phenylethane and cinnamene selectivity of the catalyst for toluene methanol side-chain alkylation reaction in the prior art. The catalyst comprises the following ingredients in percentage by weight: 60 to 99 percent of mesoporous carbon material carriers, 0.1 to 30 percent of at least one oxide selected from alkali metal or alkaline-earth metal and 0.1 to 10 percent of boron oxides, wherein the alkali metal or the alkaline-earth metal and the boron oxides are loaded on the mesoporous carbon material carriers. The technical scheme of the catalyst and the preparation method thereof perfectly solves the problems in the prior art, and can be used in industrial production for preparing the phenylethane and the cinnamene through the toluene methanol side-chain alkylation reaction.

Description

Be used for methylbenzene methanol side chain alkylation catalyst for reaction and preparation method thereof

Technical field

The present invention relates to a kind of methylbenzene methanol side chain alkylation prepared in reaction ethylbenzene and cinnamic Catalysts and its preparation method of being used for.

Background technology

The present invention relates to a kind of toluene and methyl alcohol of can being applied to and generate ethylbenzene and styrene catalyst for reaction material and synthetic method thereof.

Toluene and methanol alkylation are to produce a cinnamic emerging synthetic route with application prospect; Sidorenko in 1967 etc. use the X type and the y-type zeolite of alkali metal ion exchange to be catalyst first; Success has been synthesized styrene with toluene and methyl alcohol; Received people and paid attention to widely, the research of relevant this respect is also more and more.Compare with traditional handicraft, the method has advantages such as raw material sources are wide, cost is low, energy consumption is low, pollution is few, oil both capable of using and converted products thereof, natural gas also capable of using.This reaction can be carried out under normal pressure, high temperature, big air speed, and the alkylation catalyst system therefor is X or Y molecular sieve through alkali-metal hydroxide, boric acid or phosphoric acid modification.Dehydrogenation part catalyst system therefor is identical with traditional ethylbenzene catalyst reaction catalyst system therefor.Reaction is made up of two parts, i.e. alkylated reaction and ethylbenzene dehydrogenation reaction.

Patent US 5; 015; 796 disclose a kind of method of use base catalysis agent material of the side chain alkylation reaction that is used for toluene and methyl alcohol; This method is used the zeolite molecular sieve material with high thermal stability, through using the basic treatment of alkali metal ion or alkaline-earth metal ions, has formed methylbenzene methanol side chain alkylation synthesizing ethyl benzene and cinnamic catalyst material with side chain alkylation catalytic activity.But the various catalyst materials that this patent is invented can not be taken into account conversion ratio and the ethylbenzene or the cinnamic selectivity of toluene simultaneously.450 ℃ of catalytic activitys, its toluene conversion is merely 6.6% with the highest K-Mg/LZ-Y52 catalyst of ethylbenzene, selectivity of styrene; And the highest LZ-Y82 catalyst of toluene conversion adds up to selectivity only to reach 0.4% at 350 ℃ ethylbenzene and styrene.Thereby conversion ratio and the selectivity that how can take into account the reaction of methylbenzene methanol side chain alkylation simultaneously become an important technology difficult problem that designs this catalysts.

We find that from the mechanism of methylbenzene methanol side chain alkylation reaction toluene is a course of reaction that needs the soda acid position to cooperate catalysis jointly simultaneously with the reaction of methyl alcohol.And because the shape requirement is not selected in this reaction, thereby we think catalyst duct configuration and reaction do not have a positive connection.And the three-dimensional dimension of toluene molecule big (0.67 * 0.48 * 0.86 nanometer); Reaction generally needs the methanol molecules space coupling of toluene molecule and activated state to react in addition; And styrene that reaction generates or ethylbenzene molecule need to remove from the catalyst activity surface as soon as possible; Vacate the reactivity room, thus this reaction for the three-dimensional dimension of the inside of catalyst carrier also be have necessarily required.Because the aperture of general zeolite molecular sieve is less, usually between the 0.3-0.8 nanometer, makes reactant such as toluene, ethylbenzene, styrene or the diffusion of product molecule in the duct become and very be difficult for.So more document also has report, the catalytic activity that the ZSM-5 molecular sieve with smaller aperture due (about 0.6 nanometer) carries out the methylbenzene methanol side chain alkylation reaction after the alkali metal treated is far below the relative aperture 13X zeolite molecular sieve of big (about 1.0 nanometers) more.So the size in aperture, duct has constituted the major reason of decision methylbenzene methanol side chain alkylation reacting catalytic performance quality.And, about 800 meters squared per gram of the specific area of 13X zeolite molecular sieve, the specific area of ZSM-5 molecular sieve is about 350 meters squared per gram, and bigger specific area also is 13X zeolite molecular sieve material performance another reason preferably in this catalytic reaction.Can know that from above analysis the aperture response of catalyst carrier material is one of key factor that influences this catalysts performance.

In recent years, Metaporous silicon dioxide material is a kind of emerging porous molecular sieve materials with big bore dia, but because the thermal stability of this material is relatively poor, uses the life-span in catalytic reaction process shorter, general less being applied in the commercial production.Patent CN1834203 discloses a kind of new meso-porous carbon material (FDU-14, FDU-15 and FDU-16).This material has orderly than macropore (2～4 nanometer) and size homogeneous structural; And have huge specific area (1200 meters squared per gram) and extraordinary heat endurance, thereby be a kind of carrier of very desirable side chain alkylation catalytic reaction agent material as toluene and methyl alcohol.And the emerging meso-porous carbon material of this type does not have to use the report in the side chain alkylation reaction of toluene and methyl alcohol.

Summary of the invention

One of technical problem to be solved by this invention be catalyst of the prior art be used for methylbenzene methanol side chain alkylation reaction exist toluene conversion low with ethylbenzene, problem that selectivity of styrene is lower, a kind of new methylbenzene methanol side chain alkylation catalyst for reaction is provided.This catalyst is used for the advantage that methylbenzene methanol side chain alkylation reaction has higher toluene conversion and ethylbenzene, selectivity of styrene.Two of technical problem to be solved by this invention provides a kind of preparation method who adapts with one of technical solution problem catalyst system therefor.

For one of solving the problems of the technologies described above, the technical scheme that the present invention adopts is following: a kind of methylbenzene methanol side chain alkylation catalyst for reaction that is used for comprises following component by weight percentage: a) 60～99% meso-porous carbon material carriers; With load b on it) 0.1～30% be selected from least a oxide in alkali metal or the alkaline-earth metal; C) oxide of 0.1～10% boron.

In the technique scheme, the meso-porous carbon material preferred version is selected from least a among FDU-14, FDU-15, FDU-16, CMK-1, CMK-2, CMK-3, CMK-4 or the CMK-5; Meso-porous carbon material carrier consumption preferable range is 80～98% by weight percentage; Alkali metal or alkaline-earth metal preferred version are selected from and contain at least a in sodium, potassium, rubidium, caesium, magnesium, calcium or the barium; Alkali metal or alkaline earth oxide consumption preferable range are 1～10% by weight percentage, and boron oxide compound consumption weight percent meter preferable range is 0.1～5%; The catalyst preferred version is to comprise also in the catalyst that 0.1～10% is selected from least a in lanthanum, cerium or the Zirconium oxide by weight percentage.

For solve the problems of the technologies described above two, the technical scheme that the present invention adopts is following: a kind of preparation method who is used for methylbenzene methanol side chain alkylation catalyst for reaction may further comprise the steps:

(1) aequum is selected from alkali metal or alkaline earth metal compounds, the compound of boron and at least a compound that is selected from lanthanum, cerium or the zirconium of non-imposed adding are processed solution I;

(2) method with load is loaded to the active principle in the solution I on the meso-porous carbon material carrier, makes catalyst precarsor I;

(3) with catalyst precarsor I roasting 1～12 hour under 300～500 ℃ of conditions, obtain catalyst I.

The definition of methanol conversion, aromatic hydrocarbon productive rate is following among the present invention:

Because it is carrier that the present invention adopts meso-porous carbon material; This carrier has about 1200～2000 meters squared per gram of high specific area and bigger duct size (2～6 nanometer); The alkaline element load that catalysis is essential is gone in the meso-porous carbon material; And toluene is a course of reaction that needs the soda acid position to cooperate catalysis jointly simultaneously with the reaction of methyl alcohol; Because this reaction do not select the shape requirement, the characteristic of this Large ratio surface and macropore can increase toluene and methanol molecules are carried out basic sites catalysis in inside, duct catalytic efficiency greatly.And the three-dimensional dimension of toluene molecule big (0.67 * 0.48 * 0.86 nanometer); Reaction generally needs the methanol molecules space coupling of toluene molecule and activated state to react in addition; And styrene that reaction generates or ethylbenzene molecule need to remove from the catalyst activity surface as soon as possible; Vacate the reactivity room,, play an important role for the catalytic activity of this reaction and the raising of selectivity of product so catalyst carrier inside has bigger duct.This also is that we use the embodiment catalytic performance of the bigger meso-porous carbon material in aperture to be superior to one of major reason of comparative example.And, methylbenzene methanol side chain alkylation reaction needed soda acid complex reaction, thereby regulate the catalytic performance of the embodiment catalyst material of acidity and will obviously be superior to not carrying out the embodiment catalyst material that boron element is modified having added boron element.The adjusting catalyst acid alkalescence aspect that is added in of lanthanum element also has certain effect, and the carbon distribution problem of catalyst surface is also had some improvement.In the inventive method, catalyst is carrier with the meso-porous carbon material, load above that active element cesium oxide, the oxide of boron and the oxide of non-imposed adding lanthanum; Mix in the feeding reactor in the gasification of reactor upper end with 2.0 milliliters/hour the speed and the nitrogen carrier gas of 100 ml/min at 5: 1 raw material toluene of mol ratio and methyl alcohol; Catalyst amount is 1.0 grams; Reaction temperature is 450 ℃; Reaction pressure is a normal pressure; The reaction mass air speed is 2 hours ^-1Condition under, its toluene conversion can reach 33.2%, ethylbenzene and selectivity of styrene can reach 35.2%, have obtained better technical effect.

Below through embodiment and comparative example the present invention is done further elaboration, but the present invention is not limited by following examples.

The specific embodiment

[embodiment 1]

0.1g cesium hydroxide (9%), 0.03g boric acid (0.5%) are dissolved in the 20mL water and are divided into two parts, add meso-porous carbon material (FDU-14) 1.0g among a therein 10mL, stir and be placed on after 6 hours in 80 ℃ of baking ovens 24 hours; The solid material of gained is put in the solution of another part 10mL again, stirred and be placed on after 6 hours in 80 ℃ of baking ovens 24 hours, take out the back and ℃ heated up 3 hours by room temperature to 400,, obtain catalyst material (catalyst I) 400 ℃ of constant temperature 3 hours at nitrogen atmosphere.

With catalyst I as catalysts; Raw material toluene and methyl alcohol were with mol ratio 5: 1; Nitrogen carrier gas with 2.0 milliliters/hour speed and 100 ml/min mixes in the feeding reactor in the gasification of reactor upper end; Raw material and 1.0 gram catalyst I contact, and reaction temperature is that 450 ℃, reaction pressure are that normal pressure, raw material weight air speed are 2 hours ^-1, reaction generates ethylbenzene and styrene.

[embodiment 2～10]

According to each step preparation and the examination catalyst of embodiment 1, just change carrier, composition, sintering temperature or the roasting time of catalyst, its condition is listed in table 1, and its appraisal result is listed in table 2.

Catalyst carrier, composition (percentage composition), sintering temperature and roasting time in each instance of table 1

Numbering Carrier Sintering temperature (℃) Roasting time (hour) Cs ₂O Rb ₂O K ₂O CaO B ₂O ₃ La ₂O ₃ CeO ₂ ZrO ₂ Embodiment 1 FDU-14 400 6 9 0 0 0 0.5 0 0 0 Embodiment 2 FDU-14 400 6 9 0 0 0 0.5 0.5 0 0 Embodiment 3 FDU-15 300 6 0 1 0 0 0.1 0 0.1 0 Embodiment 4 FDU-16 500 9 0 0 20 10 1 0.5 1.5 2 Embodiment 5 CMK-1 300 6 0 0 0.1 0 0.1 0.5 0 0 Embodiment 6 CMK-2 350 3 7 0 0 0 5 1 0 0 Embodiment 7 CMK-3 400 12 1 0 1 1 10 2 2 6 Embodiment 8 CMK-4 450 1 5 0 0 0 3 1 1 0 Embodiment 9 CMK-5 500 6 3 0 0 0 2 1 0 0 Embodiment 10 FDU-14 /CMK-5 (1∶1) 400 6 9 0 0 0 0.5 0.5 0 0 Comparative example 1 AC 400 6 9 0 0 0 0.5 0.5 0 0 Comparative example 2 CsX 400 6 0 0 0 0 0.5 0.5 0 0

Each instance performance evaluation of table 2

Numbering Toluene conversion % Aromatic hydrocarbon selective % Embodiment 1 32.5 30.1 Embodiment 2 32.7 35.5 Embodiment 3 12.6 3.7 Embodiment 4 15.8 8.5 Embodiment 5 3.5 6.3 Embodiment 6 10.2 10.8 Embodiment 7 6.8 7.2 Embodiment 8 12.5 17.2 Embodiment 9 20.7 19.6 Embodiment 10 28.8 20.5 Comparative example 1 28.7 15.0 Comparative example 2 5.66 92.5

[comparative example 1]

According to each step and condition preparation and the examination catalyst of embodiment 1, the carrier that just changes catalyst is commercialization active carbon (AC), and its condition is listed in table 1, and its appraisal result is listed in table 2.

[comparative example 2]

The carrier that changes catalyst is the CsX molecular sieve, just no longer adds cesium hydroxide according to each catalyst preparation step of embodiment 1, and checks and rates catalyst according to embodiment 1 listed condition, and its condition is listed in table 1, and its appraisal result is listed in table 2.

Claims (5)

1. one kind is used for methylbenzene methanol side chain alkylation catalyst for reaction, comprises following component by weight percentage:

A) 60～99% meso-porous carbon material carriers; With load on it

B) 0.1～30% at least a oxide that is selected from alkali metal or the alkaline-earth metal;

C) oxide of 0.1～10% boron;

Said meso-porous carbon material is selected from least a among FDU-14, FDU-15, FDU-16, CMK-1, CMK-2, CMK-3, CMK-4 or the CMK-5.

2. the methylbenzene methanol side chain alkylation catalyst for reaction that is used for according to claim 1 is characterized in that meso-porous carbon material carrier consumption is 80～98% by weight percentage.

3. the methylbenzene methanol side chain alkylation catalyst for reaction that is used for according to claim 1 is characterized in that at least a oxide consumption in alkali metal by weight percentage or the alkaline-earth metal is 1～10%; The oxide consumption of boron is 0.1～5%.

4. the methylbenzene methanol side chain alkylation catalyst for reaction that is used for according to claim 1 is characterized in that also comprising in the catalyst by weight percentage that 0.1～10% is selected from least a in lanthanum, cerium or the Zirconium oxide.

5. the said preparation method who is used for methylbenzene methanol side chain alkylation catalyst for reaction of claim 1 may further comprise the steps:

(1) aequum is selected from alkali metal or alkaline earth metal compounds, the compound of boron and at least a compound that is selected from lanthanum, cerium or the zirconium of non-imposed adding are processed solution I;

(2) method with load is loaded to the active principle in the solution I on the meso-porous carbon material carrier, makes catalyst precarsor I;

(3) with catalyst precarsor I roasting 1～12 hour under 300～500 ℃ of conditions, obtain catalyst I.