CN106140214A

CN106140214A - A kind of catalyst of preparing isobutene and its preparation method and application

Info

Publication number: CN106140214A
Application number: CN201510135814.0A
Authority: CN
Inventors: 张信伟; 张舒冬; 李�杰; 孙晓丹; 倪向前; 尹泽群; 刘全杰; 张喜文
Original assignee: China Petroleum and Chemical Corp; Sinopec Fushun Research Institute of Petroleum and Petrochemicals
Current assignee: China Petroleum and Chemical Corp; Sinopec Fushun Research Institute of Petroleum and Petrochemicals
Priority date: 2015-03-27
Filing date: 2015-03-27
Publication date: 2016-11-23
Anticipated expiration: 2035-03-27
Also published as: CN106140214B

Abstract

Open a kind of preparing isobutene catalyst of the present invention and its preparation method and application.Catalyst preparation process is as follows: (1) uses co-impregnation zinc element presoma and zr element presoma to be carried on alumina support, prepares catalyst precarsor after drying, roasting；(2) adding halogen acid solution in step (1) gained catalyst precarsor and carry out evaporation process, halogen acids addition is with zinc oxide weight content in final catalysis as 0.5%-20%, and zinc halide weight content is 10%-50% meter, obtains preparing isobutene catalyst.This catalyst can improve the selectivity of isobutene. for the reaction of bromomethane preparing isobutene.

Description

A kind of catalyst of preparing isobutene and its preparation method and application

Technical field

The present invention relates to a kind of preparing isobutene catalyst and its preparation method and application, relate in particular to a kind of halide height selectivity preparing isobutene catalyst and its preparation method and application.

Background technology

Isobutene. is a kind of important basic organic chemical industry raw material, and its derived product is numerous, and vertical industry chain is complicated, and consumption structure is diversified trend.Multiple high value-added product can be prepared for raw material, such as: multiple Organic Chemicals and the fine chemistry products such as butyl rubber, polyisobutylene, methyl tertiary butyl ether(MTBE), isoprene and lucite with isobutene..Owing to the market scale of isobutene. downstream product constantly expands, its imbalance between supply and demand will gradually highlight, and particularly under the background of petroleum resources exhaustion day by day, the yield of isobutene. has become the critical bottleneck of restriction downstream industry development.Therefore, the isobutene. syntheti c route of exploitation Non oil-based route, extremely the most urgent.

Methane is the main component of natural gas, the important research content during therefore methane trans-utilization just becomes gas chemical industry's technology.The most in recent years, develop fast development at shale gas, if it is possible to produce isobutene. from methane, an important approach will be provided for obtaining isobutene..But methane stable in properties, the most easily-activated, become the bottleneck of methane chemical utilization.Both at home and abroad many researcheres carry out methane activation, Study on Transformation one after another, among these, methane transformation technology again after halogen functional groupization, it is expected to become an important breakthrough mouth of a solution methane transformation technology difficult problem.

Bromomethane is important methane halides, can the many chemical products of preparation from bromomethane.Chinese patent CN 101041609A, CN 101284232A disclose one by methane at oxygen and HBr/H₂Being converted into bromomethane under the effect of O, then bromomethane reacts the method generating C3 ~ C13 mixing high-carbon hydrocarbon further, and the hydrocarbon selective of more than C5 is 70%.Wherein, HBr for methane bromination, then discharges in first reactor in second reactor, recovered after be used further in back reaction, it is achieved the recycling of HBr.(CN 102527427A, the Jieli such as Wang Ye He, Ting Xu, Zhihui Wang, et.al. Angew. Chem. Int. Ed. 2012,51,2438-2442) modified molecular sieve catalyst disclosing a kind of halide propylene and preparation method thereof.By using fluorochemical moditied processing molecular sieve, obtaining a kind of containing appropriate microporous structure and the catalyst of acidity, this catalyst can effectively be catalyzed halide and be converted into the reaction of propylene.Prepared catalyst one way bromomethane conversion ratio in the reaction that bromomethane is preparing propylene transformed is 35 ~ 99%, and the selectivity of propylene is 27 ~ 70%；In the reaction that chloromethanes is preparing propylene transformed, one way methyl chloride conversion rate is 30 ~ 99%, and the selectivity of propylene is 15 ~ 70%.Ivan M. Lorkovic et al. (Ivan M. Lorkovic, Aysen Yilmaz, Gurkan A. Yilmaz, et al. Catalysis Today, 2004,98,317-322) it is also proposed that generate bromo-hydrocarbons with bromine with the alkane reaction in natural gas, then on metal oxide catalyst, bromo-hydrocarbons is converted into dimethyl ether, methanol and metal bromide, obtain metal-oxide after metal bromide oxygen recovery and discharge simple substance bromine, completing the circulation of bromine.

At present, it is mainly methanol and dimethyl ether about purpose product in the existing document that halide converts, additionally also have acetic acid, higher hydrocarbons, ethylene and propylene, and in the technology with alkene as target product, product mostly is ethylene, propylene, and single selectivity of product is the highest, and not yet find the relevant report of bromomethane high selectivity isobutene..

Summary of the invention

For the deficiencies in the prior art, the invention provides a kind of halide height selectivity preparing isobutene catalyst and its preparation method and application.

A kind of preparation method of preparing isobutene catalyst, including following process:

(1) use co-impregnation zinc element presoma and zr element presoma to be carried on alumina support, after drying, roasting, prepare catalyst precarsor；

(2) adding halogen acid solution in step (1) gained catalyst precarsor and carry out evaporation process, halogen acids addition is with zinc oxide weight content in final catalysis as 0.5%-20%, and zinc halide weight content is 10%-50% meter, obtains preparing isobutene catalyst.

The inventive method, described in step (1), zinc element presoma is inorganic salt or organic salt, preferably zinc nitrate, zinc chloride, zinc acetate, more preferably zinc nitrate.

The inventive method, described in step (1), the presoma of zr element is inorganic salt or organic salt, preferably zirconium nitrate, zirconium oxychloride, more preferably zirconium nitrate.

The inventive method, in step (1), catalyst carrier by it is well known that method preparation and can make suitable particle shape according to the needs used, as made bar shaped, sheet shape, cylindricality, spherical etc..Shaping can be carried out by this area general knowledge.

The inventive method, described in step (1), baking temperature is 50 DEG C-200 DEG C, preferably 60 DEG C-150 DEG C, more preferably 80 DEG C-120 DEG C；Drying time is 1h-24h, preferably 4h-8h；Can be vacuum drying time dry, it is also possible to for being dried under the conditions of inert gas shielding, it is also possible to be dried in air atmosphere.

The inventive method, described in step (1), sintering temperature is 200 DEG C-800 DEG C, preferably 400 DEG C-600 DEG C；Roasting time is 1h-24h, preferably 4h-8h；It can be roasting under the conditions of inert gas shielding during roasting, it is also possible to roasting in air atmosphere.

The inventive method, described in step (2), halogen acid solution is hydrochloric acid, hydrobromic acid, Fluohydric acid., preferably hydrobromic acid solution；Solution concentration is 1wt%-40wt%, preferably 10wt%-40wt%, more preferably 20wt%-40wt%.

The inventive method, is placed in step (1) gained sample in rotary evaporator in step (2), is warming up to 20 DEG C-90 DEG C, preferably 40 DEG C-80 DEG C；It is subsequently adding halogen acid solution and carries out rotary evaporation process；The process time is 0.5h-16h, preferably 1h-8h, more preferably 1h-4h；Material after process can be dried under the conditions of inert gas shielding, it is also possible to is dried in air atmosphere；Baking temperature is 50 DEG C-200 DEG C, preferably 60 DEG C-150 DEG C, more preferably 80 DEG C-120 DEG C；Drying time is 1h-48h, preferably 2h-36h, more preferably 2h-24h.

A kind of preparing isobutene catalyst, based on the weight content of catalyst, zinc oxide content is 0.5%-20%, preferably 1%-15%, further preferred 1%-9%；Zinc halide content is 10%-50%, preferably 15%-45%, further preferred 18%-39%；Auxiliary agent zirconia content is 0.1%-20%, preferably 0.1%-15%, more preferably 0.5%-10%.Described zinc halide includes one or more in zinc fluoride, zinc chloride, zinc bromide, zinc iodide, preferably zinc bromide.

In above-mentioned preparing isobutene catalyst, less than 450 DEG C total acid content (NH₃-TPD) it is 0.5mmol/g-1.3mmol/g, preferably 0.6mmol/g-1.2mmol/g, more preferably 0.7mmol-1.1mmol/g；The acid content of 250 DEG C-350 DEG C accounts for the 20%-90% of less than 450 DEG C total acid contents, preferably 30%-80%, more preferably 40%-80%.

The application of above-mentioned preparing isobutene catalyst, with halide as raw material, reaction temperature is 150 DEG C-350 DEG C, preferably 180 DEG C-300 DEG C, more preferably 200 DEG C-270 DEG C；Reaction pressure is 0.1MPa-5MPa, preferably 0.1MPa-3MPa；Air speed is 50h^-1-1000h^-1, preferably 200h^-1-500h^-1, needing catalyst is carried out activation processing before charging, the content of halogen activated to catalyst is the 20%-90%, preferably 30%-80%, further preferred 40%-80% of total halogen content in reduction procatalyst.

In above-mentioned application, a kind of concrete activated process is as follows: by catalyzer temperature-elevating to 300 DEG C-600 DEG C under inert atmosphere, preferably 350 DEG C-550 DEG C；Then passing to air speed is 200h^-1-2000h^-1, preferably 500h^-1-1000h^-1Hydrogen or the mixed gas of hydrogen and noble gas, at 0.1MPa-0.5MPa, preferably 0.1MPa-0.3MPa, after processing 2h-16h, preferably 4h-8h, be down to reaction temperature and be passed through halide and react.In described gaseous mixture, hydrogen volume percentage composition is 10%-95%, preferably 30%-90%, more preferably 50%-90%.

In above-mentioned application, raw material can also be the mixed gas of halide and noble gas, and in mixed gas, the volumetric concentration of halide is 10%-90%, preferably 30%-80%.

Noble gas involved in above-mentioned application is the gas that nitrogen, argon, helium etc. do not occur chemical reaction under the conditions of involved in the present invention, preferably nitrogen.

In above-mentioned application, halide raw material can be a halide, methylene halide, three halides, preferably one bromomethane, methylene bromide, bromoform, more preferably one bromomethane.

In above-mentioned application, the reaction of halide preparing isobutene can be carried out, such as fixed bed, fluid bed, fixed fluidized bed, moving bed, the reactor of the form such as slurry bed system or ebullated bed, preferably fixed bed, fluidized-bed reactor in existing any form reactor.

Compared with prior art, bromomethane height can be optionally converted into isobutene. by the method that the present invention relates to.The inventive method uses hydrobromic acid solution that catalyst is carried out halogenation treatment, can be regulated and controled the activation degree of depth of catalyst by the treatment conditions of regulation hydrobromic acid solution, make the active center controllable precise of catalyst；The method also have simple to operate, be prone to industrialized advantage.Bromomethane of the present invention converts preparing isobutene method and has reaction condition gentleness, selectivity of product advantages of higher, easily realizes industrialization, and application prospect is boundless.

Detailed description of the invention

Further illustrate technology contents and the effect of the present invention below in conjunction with embodiment, but be not intended to the present invention.Catalyst acidimetric estimation uses NH₃-TPD method, the INSTRUMENT MODEL of employing is MICROMERITICS company of U.S. AutoChem 2920 chemical adsorption instruments, concrete to measure process as follows: sample being cooled to 150 DEG C by helium purge after 1 hour at 450 DEG C, introduces the mixed gas of ammonia and helium, ammonia volume content 10%, Pulse adsorption reaches balance for five times；Helium purge 2 hours, then carries out ammonia with the programming rate temperature programming of 10 DEG C/min and is desorbed to 450 DEG C；Ammonia after desorption uses the detection of TCD detector, quantitative Analysis catalyst surface acid amount.

Embodiment 1

Weigh appropriate zinc nitrate, zirconium nitrate is dissolved in deionized water, uses equi-volume impregnating to be carried on alumina support, and 120 DEG C of dry 4h, 350 DEG C of roasting 8h prepare catalyst precarsor.Processing catalyst precarsor with 20wt% hydrobromic acid solution in a rotary evaporator, treatment conditions are 60 DEG C, and the time is 4h.Prepare catalyst.Catalyst weight consists of ZnBr₂Weight content is 30.1%, and ZnO weight content is 3.6%, ZrO₂Weight content is 5.1%.In catalyst, less than 450 DEG C total acid contents are 0.84mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 59.55% of less than 450 DEG C total acid contents.

Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 50%, and reaction temperature is 230 DEG C, and reaction pressure is 1MPa(absolute pressure), air speed is 500h^-1, it is passed through unstripped gas procatalyst and activates in a hydrogen atmosphere, reducing condition is 400 DEG C, 0.2MPa(absolute pressure), 1000h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 65.28%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 98.46%, selective isobutene 88.78%.

Embodiment 2

Catalyst is prepared with embodiment 1, and difference is, gained catalyst weight consists of ZnBr₂Weight content is 13.3%, and ZnO weight content is 0.6%, ZrO₂Weight content is 5.2%.In catalyst, less than 450 DEG C total acid contents are 0.72mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 50.15% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 70%, and reaction temperature is 230 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed is 200h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 51.7%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 65.57%, selective isobutene 51.75%.

Embodiment 3

Catalyst is prepared with embodiment 1, and difference is, gained catalyst weight consists of ZnBr₂Weight content is 33.6%, and ZnO weight content is 9.1%, ZrO₂Weight content is 4.9%.In catalyst, less than 450 DEG C total acid contents are 0.90mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 63.94% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 80%, and reaction temperature is 200 DEG C, and reaction pressure is 3MPa(absolute pressure), air speed is 350h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 50%, and reducing condition is 500 DEG C, 0.1MPa(absolute pressure), 500h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 45.66%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 99.02%, selective isobutene 77.63%.

Embodiment 4

Catalyst is prepared with embodiment 1, and difference is, gained catalyst weight consists of ZnBr₂Weight content is 35.4%, and ZnO weight content is 2.7%, ZrO₂Weight content is 2.3%.In catalyst, less than 450 DEG C total acid contents are 0.65mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 39.08% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 30%, and reaction temperature is 270 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed is 350h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 70%, and reducing condition is 350 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 6h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 55.9%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 88.87%, selective isobutene 86.25%.

Embodiment 5

Catalyst is prepared with embodiment 1, and difference is, gained catalyst weight consists of ZnBr₂Weight content is 20.1%, and ZnO weight content is 5.4%, ZrO₂Weight content is 8.9%.In catalyst, less than 450 DEG C total acid contents are 0.95mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 67.49% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane, and reaction temperature is 270 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed is 350h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 60%, and reducing condition is 550 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 8h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 40%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 73.85%, selective isobutene 64.69%.

Embodiment 6

Catalyst is prepared with embodiment 1, and difference is, uses 30wt% hydrobromic acid solution to process.Gained catalyst weight consists of ZnBr₂Weight content is 28.9%, and ZnO weight content is 3.5%, ZrO₂Weight content is 4.7%.In catalyst, less than 450 DEG C total acid contents are 0.96mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 68.21% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 50%, and reaction temperature is 230 DEG C, and reaction pressure is 0.1MPa(absolute pressure), air speed is 500h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.2MPa(absolute pressure), 1000h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 56.46%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 77.55%, selective isobutene 78.35%.

Embodiment 7

Catalyst is prepared with embodiment 1, and difference is, uses 40wt% hydrobromic acid solution to process, and gained catalyst weight consists of ZnBr₂Weight content is 20.6%, and ZnO weight content is 1.6%, ZrO₂Weight content is 4.2%.In catalyst, less than 450 DEG C total acid contents are 0.99mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 70.34% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 80%, and reaction temperature is 200 DEG C, and reaction pressure is 3MPa(absolute pressure), air speed is 350h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 90%, and reducing condition is 500 DEG C, 0.1MPa(absolute pressure), 500h^-1, recovery time 6h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 50.22%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 45.44%, selective isobutene 31.85%.

Embodiment 8

Catalyst is prepared with embodiment 1, and difference is, halogenation treatment temperature is 20 DEG C, and gained catalyst weight consists of ZnBr₂Weight content is 25.8%, and ZnO weight content is 4.6%, ZrO₂Weight content is 4.9%.In catalyst, less than 450 DEG C total acid contents are 0.80mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 52.39% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 70%, and reaction temperature is 230 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed is 200h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 37.84%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 82.63%, selective isobutene 69.87%.

Embodiment 9

Catalyst is prepared with embodiment 1, and difference is, halogenation treatment temperature is 40 DEG C, and gained catalyst weight consists of ZnBr₂Weight content is 27.8%, and ZnO weight content is 3.3%, ZrO₂Weight content is 4.5%.In catalyst, less than 450 DEG C total acid contents are 0.85mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 56.60% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 70%, and reaction temperature is 230 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed is 200h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 61.62%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 99.12%, selective isobutene 81.14%.

Embodiment 10

Catalyst is prepared with embodiment 1, and difference is, halogenation treatment temperature is 80 DEG C, and gained catalyst weight consists of ZnBr₂Weight content is 17.4%, and ZnO weight content is 0.8%, ZrO₂Weight content is 4.2%.In catalyst, less than 450 DEG C total acid contents are 1.07mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 70.07% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 70%, and reaction temperature is 230 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed is 200h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 60.64%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 39.38%, selective isobutene 24.15%.

Embodiment 11

Catalyst is prepared with embodiment 1, and difference is, the halogenation treatment time is 1h, and gained catalyst weight consists of ZnBr₂Weight content is 20.2%, and ZnO weight content is 5.5%, ZrO₂Weight content is 4.8%.In catalyst, less than 450 DEG C total acid contents are 0.81mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 56.42% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 70%, and reaction temperature is 230 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed is 200h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 51.85%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 88.96%, selective isobutene 49.34%.

Embodiment 12

Catalyst is prepared with embodiment 1, and difference is, the halogenation treatment time is 8h, and gained catalyst weight consists of ZnBr₂Weight content is 28.6%, and ZnO weight content is 2.2%, ZrO₂Weight content is 4.5%.In catalyst, less than 450 DEG C total acid contents are 0.96mmol/g, and the acid content of 250 DEG C-350 DEG C accounts for the 74.78% of less than 450 DEG C total acid contents.Bromomethane converts preparing isobutene reaction to be carried out in flowing micro fixed-bed reactor continuously.Catalyst loading amount 5g, unstripped gas is a bromomethane and nitrogen mixed gas, and wherein monobromo methane volumetric content is 70%, and reaction temperature is 230 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed is 200h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, and in mixed gas, hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 4h, reduction rear catalyst in content of halogen be reduction procatalyst in total halogen content 46.31%.After stable reaction one hour, sampling analysis.Bromomethane conversion ratio 65.64%, selective isobutene 40.83%.

Comparative example 1

Catalyst is prepared with embodiment 1.Evaluating catalyst condition is same as in Example 1, and difference is, does not carries out reduction treatment.Bromomethane conversion ratio 15.64%, selective isobutene 0%.

Comparative example 2

Catalyst is prepared with embodiment 1, and difference is not carry out hydrobromic acid solution process,.Evaluating catalyst condition is same as in Example 1, bromomethane conversion ratio 98.34%, selective isobutene 0%.

Comparative example 3

Catalyst is prepared with embodiment 1.Evaluating catalyst condition is same as in Example 1, and difference is, is zinc by zinc bromide Restore All.Bromomethane conversion ratio 1.21%, selective isobutene 0 %.

Claims

1. the preparation method of a preparing isobutene catalyst, it is characterised in that: include following process:

Method the most according to claim 1, it is characterised in that: described in step (1), zinc element presoma is zinc nitrate, zinc chloride or zinc acetate.

Method the most according to claim 1, it is characterised in that: described in step (1), the presoma of zr element is zirconium nitrate or zirconium oxychloride.

Method the most according to claim 1, it is characterised in that: described in step (1), baking temperature is 50 DEG C-200 DEG C；Drying time is 1h-24h.

Method the most according to claim 1, it is characterised in that: described in step (1), sintering temperature is 200 DEG C-800 DEG C；Roasting time is 1h-24h.

Method the most according to claim 1, it is characterised in that: described in step (2), halogen acid solution is hydrochloric acid solution, hydrobromic acid solution or hydrofluoric acid solution；Solution concentration is 1wt%-40wt%.

Method the most according to claim 6, it is characterised in that: described halogen acid solution is hydrobromic acid solution；Solution concentration is 10wt%-40wt%.

Method the most according to claim 1, it is characterised in that: step (1) gained sample is placed in rotary evaporator by step (2), is warming up to 20 DEG C-90 DEG C；It is subsequently adding halogen acid solution and carries out rotary evaporation process；The process time is 0.5h-16h.

Method the most according to claim 9, it is characterised in that: the material after process is dried under the conditions of inert gas shielding；Baking temperature is 50 DEG C-200 DEG C；Drying time is 1h-48h.

10. the catalyst that prepared by claim 1 to 9 either method, it is characterised in that: based on the weight content of catalyst, zinc oxide content is 0.5%-20%；Zinc halide content is 10%-50%；Auxiliary agent zirconia content is 0.1%-20%, and described zinc halide includes one or more in zinc fluoride, zinc chloride, zinc bromide, zinc iodide.

11. catalyst according to claim 10, it is characterised in that: based on the weight content of catalyst, zinc oxide content is 1%-15%；Zinc halide content is 15%-45%；Auxiliary agent zirconia content is 0.1%-15%, and described zinc halide is zinc bromide.

12. catalyst according to claim 11, it is characterised in that: based on the weight content of catalyst, zinc oxide content is 1%-9%；Zinc halide content is 18%-39%；Auxiliary agent zirconia content is 0.5%-10%.

13. catalyst according to claim 10, it is characterised in that: in catalyst, less than 450 DEG C total acid contents are 0.5mmol/g-1.3mmol/g；The acid content of 250 DEG C-350 DEG C accounts for the 20%-90% of less than 450 DEG C total acid contents.

Described in 14. claim 10, catalyst is in the application to isobutene., it is characterised in that: with halide as raw material, reaction temperature is 150 DEG C-350 DEG C；Reaction pressure is 0.1MPa-5MPa；Air speed is 50h^-1-1000h^-1, needing catalyst is carried out activation processing before charging, the content of halogen activated to catalyst is the 20%-90% of total halogen content in reduction procatalyst.

15. application according to claim 14, it is characterised in that: reaction temperature is 180 DEG C-300 DEG C；Reaction pressure is 0.1MPa-3MPa；Air speed is 200h^-1-500h^-1, needing catalyst is carried out activation processing before charging, the content of halogen activated to catalyst is the 30%-80% of total halogen content in reduction procatalyst.

16. want the application described in 14 according to right, it is characterised in that: activated process is as follows: by catalyzer temperature-elevating to 300 DEG C-600 DEG C under inert atmosphere；Then passing to air speed is 200h^-1-2000h^-1Hydrogen or the mixed gas of hydrogen and noble gas, after 0.1MPa-0.5MPa processes 2h-16h, be down to reaction temperature and be passed through halide and react, in described gaseous mixture, hydrogen volume percentage composition is 10%-95%.

17. want the application described in 16 according to right, it is characterised in that: by catalyzer temperature-elevating to 350 DEG C-550 DEG C under inert atmosphere；Then passing to air speed is 500h^-1-1000h^-1Hydrogen or the mixed gas of hydrogen and noble gas, after 0.1MPa-0.3MPa processes 4h-8h, be down to reaction temperature and be passed through halide and react, in described gaseous mixture, hydrogen volume percentage composition is 30%-90%.

18. want the application described in 14 according to right, it is characterised in that: raw material is the mixed gas of halide and noble gas, and in mixed gas, the volumetric concentration of halide is 10%-90%.

19. want the application described in 14 according to right, it is characterised in that: halide raw material is a halide, methylene halide or three halides.

20. want the application described in 19 according to right, it is characterised in that: halide raw material is a bromomethane, methylene bromide or bromoform.

21. want the application described in 14 according to right, it is characterised in that: the reaction of halide preparing isobutene is carried out in fixed bed, fluid bed, fixed fluidized bed, moving bed, slurry bed system or fluidized bed reactor.