CN106140258B - It is a kind of using modified zsm-5 zeolite as catalyst of carrier and preparation method thereof and its application in preparing isobutene - Google Patents

Abstract

The present invention provides a kind of using modified zsm-5 zeolite as catalyst of carrier and preparation method thereof and its application in preparing isobutene.The preparation method of the catalyst, comprises the following processes: (1) Hydrogen ZSM-5 molecular sieve carrier being carried out aqueous slkali, acid solution and magnesium salt solution impregnation respectively；It (2) will be in the zinc oxide Hydrogen ZSM-5 molecular sieve carrier that is introduced to that treated；(3) bromination processing is carried out to the Hydrogen ZSM-5 molecular sieve carrier after introducing zinc oxide, bromination zinc oxide weight content into catalyst is 0.5%-20%, preferably 1%-15%, further preferably 1%-9%, zinc bromide weight content is 10%-50%, preferably 15%-45%, further preferably 18%-39%.The catalyst of this method preparation can significantly improve the selectivity of isobutene.

Description

It is a kind of using modified zsm-5 zeolite as catalyst of carrier and preparation method thereof and its Application in preparing isobutene

Technical field

The present invention relates to it is a kind of using modified zsm-5 zeolite as catalyst of carrier and preparation method thereof and its in isobutyl processed Application in alkene.

Background technique

Isobutene is a kind of important basic organic chemical industry raw material, and derived product is numerous, and vertical industry chain is complicated, is disappeared Take structure in diversified trend.A variety of high value-added products can be prepared by raw material of isobutene, such as: butyl rubber, gather it is different A variety of Organic Chemicals such as butylene, methyl tertiary butyl ether(MTBE), isoprene and organic glass and fine chemistry product.Due to isobutyl The market scale of alkene downstream product constantly expands, and imbalance between supply and demand will be protruded gradually, especially increasingly depleted in petroleum resources Under background, the yield of isobutene has become the critical bottleneck for restricting downstream industry development.Therefore, the isobutyl of Non oil-based route is developed Alkene preparation route is extremely urgent.

Methane is the main component of natural gas, therefore methane trans-utilization important grinding of just becoming in gas chemical industry's technology Study carefully content.Especially in recent years, under the overall background of shale gas development and utilization, if it is possible to realize from methane and produce isobutyl Alkene will provide a new approach to obtain isobutene.But methane property is stablized, and it is not easily-activated, become methane chemical industry benefit Bottleneck.Domestic and international many researchers carry out methane activation, Study on Transformation one after another, and among these, methane is through halogen functional groupization The technology converted again afterwards is expected to become an important breakthrough mouth for solving methane transformation technology problem.

Many chemical products can be prepared from halide.Chinese patent CN 101041609A, CN 101284232A disclose it is a kind of by methane in oxygen and HBr/H₂Bromomethane is converted under the action of O, then bromomethane The further method that reaction generates C3 ~ C13 mixing high-carbon hydrocarbon, the hydrocarbon selective of C5 or more are 70%.Wherein, HBr is at first It is used for methane bromination in reactor, is then discharged in second reactor, is used further in back reaction, realizes after recovered The recycling of HBr.(CN 102527427A, Jieli He, Ting Xu, the Zhihui Wang, et.al. such as Wang Ye Angew. Chem. Int. Ed. 2012,51,2438-2442) disclose a kind of modified molecules of halide propylene Sieve catalyst and preparation method thereof.By using fluorochemical moditied processing molecular sieve, obtains one kind and contain appropriate microporous knot The catalyst of structure and acidity, the catalyst can effectively be catalyzed the reaction that halide is converted into propylene.Prepared catalysis Agent one way bromomethane conversion ratio in the preparing propylene transformed reaction of bromomethane is 35 ~ 99%, and the selectivity of propylene is 27 ~ 70%；? One way methyl chloride conversion rate is 30 ~ 99% in the preparing propylene transformed reaction of chloromethanes, 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 bromo-hydrocarbons is generated with the alkane reaction in bromine and natural gas, Then dimethyl ether, methanol and metal bromide, metal bromide oxygen are converted by bromo-hydrocarbons on metal oxide catalyst Metal oxide is obtained after gas regeneration and releases simple substance bromine, completes the circulation of bromine.

Currently, being mainly methanol, dimethyl ether, acetic acid, high-carbon about purpose product in the existing literature of halide conversion Hydro carbons, ethylene and propylene etc..In the technology using the low-carbon alkene compared with high added value as target product, single selectivity of product It is not high, not yet find the relevant report of bromomethane high selectivity isobutene.

Summary of the invention

In view of the deficiencies of the prior art, the present invention provide it is a kind of using modified zsm-5 zeolite as the catalyst of carrier and its Preparation method and its application in preparing isobutene.

It is a kind of using modified zsm-5 zeolite as the preparation method of the catalyst of carrier, comprise the following processes: (1) by Hydrogen ZSM-5 molecular sieve carrier carries out aqueous slkali, acid solution and magnesium salt solution impregnation respectively；(2) zinc oxide is introduced to processing In Hydrogen ZSM-5 molecular sieve carrier afterwards；(3) bromination processing is carried out to the Hydrogen ZSM-5 molecular sieve carrier after introducing zinc oxide, Bromination zinc oxide weight content into catalyst is 0.5%-20%, preferably 1%-15%, further preferably 1%-9%, zinc bromide Weight content is 10%-50%, preferably 15%-45%, further preferably 18%-39%.

In above-mentioned preparation method step (1), the Hydrogen ZSM-5 molecular sieve carrier can be existing commercial product, It can be prepared by those skilled in the art's well-known process.Carrier can be made or choose according to the needs of use suitable granulated State, such as bar shaped, piece shape, cylindricality, spherical shape is made, forming can be carried out by this field general knowledge.

In above-mentioned preparation method step (1), impregnation process is as follows: by Hydrogen ZSM-5 molecular sieve carrier, by 5mL/g- The liquid-solid ratio of 25mL/g is added in aqueous slkali, and preferably liquid-solid ratio is 10mL/g-20mL/g, in room temperature to 80 DEG C of stirring 0.5h- 1.5h is separated by solid-liquid separation, and obtained solid is in 80 DEG C -120 DEG C dry 6h-12h；By the sample after drying, by 10mL/g-50mL/g's Liquid-solid ratio is added in acid solution, and preferably liquid-solid ratio is 20mL/g-40mL/g, in 30 DEG C to 70 DEG C stirring 1h-3h, is separated by solid-liquid separation, Obtained solid is in 80 DEG C -120 DEG C dry 6h-12h, then at 450 DEG C of -650 DEG C of roasting 4h-8h；Roasting sample is added to It is mixed in the ratio that 1mL-5mL magnesium salt solution is added in every gram of ZSM-5 molecular sieve in magnesium salt solution containing certain mass score It closes, stands 4h-12h, preferably 6h-10h, 80 DEG C -120 DEG C dry 6h-12h change then at 450 DEG C of -650 DEG C of roasting 4h-8h The ZSM-5 molecular sieve carrier of property.Above-mentioned aqueous slkali can be NaOH, KOH or Na₂CO₃One or more of aqueous solution, alkali The concentration of solution is 0.1mol/L-2mol/L, preferably 0.5mol/L-1.5mol/L；Acid solution can be hydrochloric acid, nitric acid or sulphur One or more of acid solution, the concentration of acid solution are 0.1mol/L-5mol/L, preferably 0.5mol/L-2.5mol/L；Institute It states in modified ZSM-5 molecular sieve carrier, the weight content of magnesium based on the element in the carrier is 0.5%-10%, preferably 1%-5%.

In above-mentioned preparation method step (2), the method that the zinc oxide is introduced to modified hydrogen ZSM-5 molecular sieve carrier is Method well known to those skilled in the art can such as be introduced using impregnation method.The specific method is as follows: being impregnated using zinc solution Modified Hydrogen ZSM-5 molecular sieve carrier obtains bromomethane preparing isobutene catalyst precarsor after drying, roasting.It is described dry Dry condition is -150 DEG C of temperature 60 C, preferably 80 DEG C -120 DEG C；Time is 1h-24h, preferably 4h-8h；It can be with when dry For vacuum drying, or it is dry under the conditions of inert gas shielding, it can also dry in air atmosphere.The roasting condition For 200 DEG C -800 DEG C of temperature, preferably 400 DEG C -600 DEG C；Time is 1h-24h, preferably 4h-8h；It can be lazy when roasting It roasts, can also be roasted under the conditions of property gas shield in air atmosphere.In the above method, zinc salt can be inorganic salts, can also Think organic salt, preferably one or more of nitrate, hydrochloride, acetate, citrate.

In above-mentioned preparation method step (3), the bromination processing refers to using gas phase bromine-containing compound to load zinc oxide Sample handled.Bromine-containing compound refers to one or more of bromomethane, methylene bromide, bromoform, preferably bromine Methane.Bromination processing can also be carried out using the mixed gas of gas phase bromine-containing compound and inert gas, using mixed gas bromine When changing processing, bromomethane volumetric concentration is not less than 20%, preferably not less than 30%.Specific bromination process is as follows: will load oxygen The sample for changing zinc is placed in continuous fixed bed reactor, is warming up to 150 DEG C -400 DEG C under inert atmosphere, preferably 180 DEG C - 350 DEG C, more preferably 200 DEG C -300 DEG C are passed through gas phase bromine-containing compound gas, gas space velocity 50h^-1-1000 h^-1, preferably For 100h^-1-500h^-1；It can carry out, can also carry out under a certain pressure, system pressure 0.1MPa- in normal pressure when processing 0.5MPa(absolute pressure), preferably 0.1MPa-0.3MPa(absolute pressure), the processing time is 0.5h-8h, preferably 1h-4h.

In above-mentioned preparation method step (3), related inert gas is nitrogen, argon gas, helium etc. involved by the present invention The gas not chemically reacted under the conditions of and, preferably nitrogen.

A kind of catalyst prepared using the above method, the catalyst is by zinc oxide, zinc bromide and modified ZSM-5 molecule Carrier composition is sieved, based on the weight content of catalyst, zinc oxide content 0.5%-20%, preferably 1%-15%, further preferably For 1%-9%, bromination Zn content is 10%-50%, preferably 15%-45%, further preferably 18%-39%, modified zsm-5 zeolite Vector contg is 40%-90%, preferably 50%-85%, further preferably 55%-80%, ZSM-5 molecular sieve carrier sial mole Than being 20 ~ 200, preferably 50 ~ 150.

In catalyst of the present invention, 450 DEG C or less total acid content (NH₃- TPD) it is 0.5mmol/g-1.3mmol/g, preferably 0.6mmol/g-1.2mmol/g, further preferred 0.7mmol-1.1mmol/g, 250 DEG C -350 DEG C of acid content account for 450 DEG C with The 20%-90% of lower total acid content, preferably 30%-80%, further preferred 40%-80%.

The above-mentioned application using the ZSM-5 molecular sieve of modification as the catalyst of carrier in preparing isobutene, including to urging Agent carries out hydrogen reducing activation, and the content of halogen in catalyst is made to restore the 20%-90% of total halogen content in procatalyst, Catalyst after activating halide with above-mentioned hydrogen reducing contacts, to prepare isobutene.

In above-mentioned application, the condition of the hydrogen reducing activation is urged before the content of halogen in catalyst is preferably restored The 30%-80% of total halogen content in agent, further preferred 40%-80%.

In above-mentioned application, the mode of hydrogen reducing activation include under an inert atmosphere by catalyzer temperature-elevating to 300 DEG C- 600℃；Then passing to air speed is 200h^-1-2000h^-1Hydrogen or hydrogen and inert gas mixed gas, in 0.1MPa- 0.5MPa keeps 2h-16h, and hydrogen volume percentage composition is 10%-95% in mixed gas；Preferably, it is warming up to 350 DEG C -550 ℃；Then passing to air speed is 500h^-1-1000h^-1Hydrogen or hydrogen and inert gas mixed gas, in 0.1MPa- 0.3MPa keeps 4h-8h, and hydrogen volume percentage composition is 30%-90% in the mixed gas.

In above-mentioned application, the halide can be one of a halide, methylene halide, three halides Or a variety of, preferably one of bromomethane, methylene bromide, bromoform or a variety of.

In above-mentioned application, the condition of the contact includes that reaction temperature is 150 DEG C -350 DEG C；Reaction pressure is 0.1MPa- 5MPa；Air speed is 50h^-1-1000h^-1；It is highly preferred that reaction temperature is 180 DEG C -300 DEG C more preferably 200-270 DEG C；Reaction Pressure is 0.1MPa-3MPa；Air speed is 200h^-1-500h^-1。

By catalyzer temperature-elevating to 300 DEG C -600 DEG C under one of above-mentioned application specific embodiment, including 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 hydrogen With the mixed gas of inert gas, in 0.1MPa-0.5MPa(absolute pressure), preferably 0.1MPa-0.3MPa(absolute pressure) processing 2h- After 16h, preferably 4h-8h, it is down to reaction temperature and is passed through halide and reacted.Hydrogen volume percentage contains in the gaseous mixture Amount is 10%-95%, preferably 30%-90%, more preferably 50%-90%.

In above-mentioned application, raw material may be the mixed gas of halide and inert gas, halogenated first in mixed gas The volumetric concentration of alkane is 10%-90%, preferably 30%-80%.

Inert gas involved in above-mentioned application is that nitrogen, argon gas, helium etc. are not sent out under the conditions of involved in the present invention The gas of biochemical reaction, preferably nitrogen.

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

Compared with prior art, catalyst prepared by the present invention can by bromomethane it is highly selective be converted into isobutene. By the method for the present invention carry out bromomethane conversion preparing isobutene reaction, 90% or more bromomethane conversion ratio, selective isobutene 55% with On.The present invention relates to bromomethane conversion preparing isobutene method for preparing catalyst it is simple, be easy to industrialize.Bromomethane conversion of the present invention Preparing isobutene method has many advantages, such as that reaction condition is mild, selectivity of product is high, industrialization easy to accomplish, and application prospect is very wide It is wealthy.

Specific embodiment

Technology contents and effect of the invention are further illustrated below with reference to embodiment, but are not so limited the present invention.

Acidimetric estimation uses NH in following embodiment and comparative example₃- TPD method, the instrument model used is the U.S. 2920 chemical adsorption instrument of MICROMERITICS company AutoChem, specific continuous mode are as follows: by sample at 450 DEG C with helium Purging was cooled to 150 DEG C after 1 hour, introduced the mixed gas of ammonia and helium, ammonia volume content 10%, reached for Pulse adsorption five times Balance；Helium purge 2 hours, ammonia is then carried out with 10 DEG C/min of heating rate temperature programming and is desorbed to 450 DEG C；After desorption Ammonia using TCD detector detect, quantitatively calculate catalyst surface acid amount.

Embodiment 1

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 50) carrier is weighed, the KOH water that 600mL concentration is 0.5 mol/L is dipped in In solution, 1.5h is stirred at room temperature, is then separated by solid-liquid separation, 120 DEG C of dry 6h；The sample after drying is dipped in 1200mL concentration again In aqueous solution of nitric acid for 0.5 mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h. Sample after weighing 20g roasting is added in the magnesium nitrate solution that 83mL concentration is 1mol/L, 12h is stood, then at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 5% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, catalyst precarsor ZnO/Mg-ZSM-5 is made in 80 DEG C of dry 8h, 600 DEG C of roasting 4h.5g catalyst precarsor is placed in company Afterflow is moved in fixed bed reactors, handles catalyst precarsor using bromomethane, treatment conditions are 250 DEG C, 0.2MPa(absolute pressure), 100h^-1, time 2h, be made bromomethane preparing isobutene catalyst, be denoted as C-1.Catalyst weight group becomes ZnBr₂Weight content is 27%, ZnO weight content are 6%, and 450 DEG C or less total acid contents are 0.82mmol/g in catalyst, and 250 DEG C -350 DEG C of acid content accounts for The 65.1% of 450 DEG C or less total acid contents.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 50%, and reaction temperature is 230 DEG C, reaction pressure For 1MPa(absolute pressure), air speed 500h^-1, it being 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, restoring the content of halogen in rear catalyst is that halogen is total in reduction procatalyst The 63.82% of content.After stable reaction one hour, sampling analysis.Reaction result is shown in Table 1.

Embodiment 2

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 100) carrier is weighed, the NaOH water that 450mL concentration is 1 mol/L is dipped in In solution, 1h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h；The sample after drying, which is dipped in 900mL concentration, again is In the aqueous hydrochloric acid solution of 1.5mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h.It weighs Sample after 20g roasting is added in the magnesium nitrate solution that 50mL concentration is 0.5mol/L, stands 12h, then dry at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 3% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, catalyst precarsor ZnO/Mg-ZSM-5 is made in 120 DEG C of dry 4h, 500 DEG C of roasting 8h.5g catalyst precarsor is placed in In continuous fixed bed reactor, catalyst precarsor is handled using the mixed gas of bromomethane and nitrogen, bromomethane volume is dense Degree is 80%, and treatment conditions are 250 DEG C, 0.3MPa(absolute pressure), 300h^-1, time 2h, obtained bromomethane preparing isobutene catalyst, note For C-2.Catalyst weight group is obtained as ZnBr₂Weight content is 30%, ZnO weight content in terms of oxide in terms of bromide It is 4%, 450 DEG C or less total acid contents are 0.89mmol/g in catalyst, and 250 DEG C -350 DEG C of acid content accounts for 450 DEG C or less total acid contents 67.3%.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 70%, and reaction temperature is 230 DEG C, reaction pressure For 2MPa(absolute pressure), air speed 200h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, mixed gas Middle hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 4h is catalyzed after reduction Content of halogen in agent is restore total halogen content in procatalyst 63.28%.After stable reaction one hour, sampling analysis.Instead 1 should be the results are shown in Table.

Embodiment 3

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 150) carrier is weighed, the Na that 300 mL concentration are 1.5mol/L is dipped in₂CO₃ In aqueous solution, 0.5h is stirred at 80 DEG C, is then separated by solid-liquid separation, 80 DEG C of dry 12h；It is dense that the sample after drying is dipped in 600mL again Degree is to stir 2h at 50 DEG C in the aqueous sulfuric acid of 2.5 mol/L, be then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roastings 6h.Sample after weighing 20g roasting is added in the magnesium nitrate solution that 33mL concentration is 0.25mol/L, stands 12h, then exist 120 DEG C of dry 12h obtain the modified zsm-5 zeolite that content of magnesium is 1% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, catalyst precarsor ZnO/Mg-ZSM-5 is made in 100 DEG C of vacuum drying 8h, 400 DEG C of roasting 8h.By 5g catalyst precarsor It is placed in continuous fixed bed reactor, handles catalyst precarsor, bromomethane body using the mixed gas of bromomethane and nitrogen Product concentration is 30%, and treatment conditions are 300 DEG C, 0.1MPa(absolute pressure), 500h^-1, time 4h, obtained bromomethane preparing isobutene catalysis Agent is denoted as C-3.Catalyst weight group is obtained as ZnBr₂Weight content is 33%, ZnO with oxide weight calculation amount in terms of bromide Content is 2%, and 450 DEG C or less total acid contents are 0.93mmol/g in catalyst, and 250 DEG C -350 DEG C of acid content accounts for 450 DEG C or less always The 70.2% of acid amount.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 80%, and reaction temperature is 200 DEG C, reaction pressure For 3MPa(absolute pressure), air speed 350h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, mixed gas Middle hydrogen volume content is 50%, and reducing condition is 500 DEG C, 0.1MPa(absolute pressure), 500h^-1, recovery time 4h is catalyzed after reduction Content of halogen in agent is restore total halogen content in procatalyst 48.32%.After stable reaction one hour, sampling analysis.Instead 1 should be the results are shown in Table.

Embodiment 4

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 100) carrier is weighed, the NaOH water that 450mL concentration is 1 mol/L is dipped in In solution, 1h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h；The sample after drying, which is dipped in 900mL concentration, again is In the aqueous hydrochloric acid solution of 1.5mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h.It weighs Sample after 20g roasting is added in the magnesium nitrate solution that 50mL concentration is 0.5mol/L, stands 12h, then dry at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 3% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, catalyst precarsor ZnO/Mg-ZSM-5 is made in 500 DEG C of roasting 8h.5g catalyst precarsor is placed in continuous flowing to fix In bed reactor, catalyst precarsor is handled using bromomethane, treatment conditions are 200 DEG C, 0.3MPa(absolute pressure), 300h^-1, the time 1h is made bromomethane preparing isobutene catalyst, is denoted as C-4.Catalyst weight group is obtained as ZnBr₂Contained with bromide weight calculation amount Amount be 18%, ZnO weight content in terms of oxide is 2%, and 450 DEG C or less total acid contents are 0.71mmol/g in catalyst, 250 DEG C- 350 DEG C of acid content accounts for the 61.5% of 450 DEG C or less total acid contents.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 30%, and reaction temperature is 270 DEG C, reaction pressure For 2MPa(absolute pressure), air speed 350h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, mixed gas Middle hydrogen volume content is 70%, and reducing condition is 350 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 6h is catalyzed after reduction Content of halogen in agent is restore total halogen content in procatalyst 57.28%.After stable reaction one hour, sampling analysis.Instead 1 should be the results are shown in Table.

Embodiment 5

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 100) carrier is weighed, the NaOH water that 450mL concentration is 1 mol/L is dipped in In solution, 1h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h；The sample after drying, which is dipped in 900mL concentration, again is In the aqueous hydrochloric acid solution of 1.5mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h.It weighs Sample after 20g roasting is added in the magnesium nitrate solution that 50mL concentration is 0.5mol/L, stands 12h, then dry at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 3% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, 100 DEG C of dry 6h roast 6h under 500 DEG C of nitrogen protections, obtained catalyst precarsor ZnO/Mg-ZSM-5.5g is catalyzed Agent precursor is placed in continuous fixed bed reactor, handles catalyst precarsor, bromine using the mixed gas of bromomethane and nitrogen Volume percent methane is 70%, and treatment conditions are 200 DEG C, 0.3MPa(absolute pressure), 300h^-1, time 2h, obtained bromomethane isobutyl Alkene catalyst, is denoted as C-5.Catalyst weight group is obtained as ZnBr₂Weight content is 39%, ZnO with oxide in terms of bromide Counting weight content is 6%, and 450 DEG C or less total acid contents are 0.96mmol/g in catalyst, and 250 DEG C -350 DEG C of acid content accounts for 450 DEG C The 75.4% of following total acid content.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane, and reaction temperature is 270 DEG C, and reaction pressure is 2MPa(absolute pressure), air speed 350h^-1.Before being passed through unstripped gas, Catalyst activates under the mixed atmosphere of hydrogen, and hydrogen volume content is 60% in mixed gas, and reducing condition is 550 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 8h, restoring the content of halogen in rear catalyst is that halogen is total in reduction procatalyst The 41.29% of content.After stable reaction one hour, sampling analysis.Reaction result is shown in Table 1.

Embodiment 6

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 100) carrier is weighed, the NaOH water that 450mL concentration is 1 mol/L is dipped in In solution, 1h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h；The sample after drying, which is dipped in 900mL concentration, again is In the aqueous hydrochloric acid solution of 1.5mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h.It weighs Sample after 20g roasting is added in the magnesium nitrate solution that 50mL concentration is 0.5mol/L, stands 12h, then dry at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 3% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, 4h is dried under 120 DEG C of nitrogen atmospheres, roasts 4h under 500 DEG C of nitrogen atmospheres, catalyst precarsor ZnO/Mg-ZSM- is made 5.5g catalyst precarsor is placed in continuous fixed bed reactor, handles catalyst precarsor, treatment conditions using bromomethane It is 250 DEG C, 0.2MPa(absolute pressure), 100h^-1, time 1h is denoted as C-6.Catalyst weight group is obtained as ZnBr₂In terms of bromide Weight content is that 35%, ZnO weight content in terms of oxide is 9%, and 450 DEG C or less total acid contents are 0.94mmol/g in catalyst, 250 DEG C -350 DEG C of acid content accounts for the 72.9% of 450 DEG C or less total acid contents.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 50%, and reaction temperature is 230 DEG C, reaction pressure For 0.1MPa(absolute pressure), air speed 500h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, gaseous mixture Hydrogen volume content is 80% in body, and reducing condition is 450 DEG C, 0.2MPa(absolute pressure), 1000h^-1, recovery time 4h urges after reduction Content of halogen in agent is restore total halogen content in procatalyst 59.83%.After stable reaction one hour, sampling analysis. Reaction result is shown in Table 1.

Embodiment 7

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 100) carrier is weighed, the NaOH water that 450mL concentration is 1 mol/L is dipped in In solution, 1h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h；The sample after drying, which is dipped in 900mL concentration, again is In the aqueous hydrochloric acid solution of 1.5mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h.It weighs Sample after 20g roasting is added in the magnesium nitrate solution that 50mL concentration is 0.5mol/L, stands 12h, then dry at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 3% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, catalyst precarsor ZnO/Mg-ZSM-5 is made in 120 DEG C of dry 4h, 500 DEG C of roasting 4h.5g catalyst precarsor is placed in In continuous fixed bed reactor, catalyst precarsor is handled using the mixed gas of bromomethane and nitrogen, bromomethane volume is dense Degree is 90%, and treatment conditions are 300 DEG C, 0.1MPa(absolute pressure), 500h^-1, time 4h, obtained bromomethane preparing isobutene catalyst, note For C-7.Catalyst weight group is obtained as ZnBr₂Weight content is 20%, ZnO weight content in terms of oxide in terms of bromide It is 1%, 450 DEG C or less total acid contents are 0.74mmol/g in catalyst, and 250 DEG C -350 DEG C of acid content accounts for 450 DEG C or less total acid contents 63.6%.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 80%, and reaction temperature is 200 DEG C, reaction pressure For 3MPa(absolute pressure), air speed 350h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, mixed gas Middle hydrogen volume content is 90%, and reducing condition is 500 DEG C, 0.1MPa(absolute pressure), 500h^-1, recovery time 6h is catalyzed after reduction Content of halogen in agent is restore total halogen content in procatalyst 52.83%.After stable reaction one hour, sampling analysis.Instead 1 should be the results are shown in Table.

Comparative example 1

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 100) carrier is weighed, the NaOH water that 450mL concentration is 1 mol/L is dipped in In solution, 1h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h；The sample after drying, which is dipped in 900mL concentration, again is In the aqueous hydrochloric acid solution of 1.5mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h.It weighs Sample after 20g roasting is added in the magnesium nitrate solution that 50mL concentration is 0.5mol/L, stands 12h, then dry at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 3% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, 120 DEG C of dry 4h, 500 DEG C of roasting 4h are made catalyst Z nO/Mg-ZSM-5, are denoted as D-1.Obtain catalyst weight It is 20% that group, which becomes ZnO weight content in terms of oxide, and 450 DEG C or less total acid contents are 0.41mmol/g in catalyst, 250 DEG C- 350 DEG C of acid content accounts for the 37.8% of 450 DEG C or less total acid contents.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 30%, and reaction temperature is 270 DEG C, reaction pressure For 2MPa(absolute pressure), air speed 350h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, mixed gas Middle hydrogen volume content is 70%, and reducing condition is 350 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 6h.Stable reaction one After hour, sampling analysis.Reaction result is shown in Table 1.

Comparative example 2

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 100) carrier is weighed, the NaOH water that 450mL concentration is 1 mol/L is dipped in In solution, 1h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h；The sample after drying, which is dipped in 900mL concentration, again is In the aqueous hydrochloric acid solution of 1.5mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h.It weighs Sample after 20g roasting is added in the magnesium nitrate solution that 50mL concentration is 0.5mol/L, stands 12h, then dry at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 3% in 550 DEG C of roasting 6h.

It weighs appropriate zinc nitrate to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier is sieved, catalyst precarsor ZnO/Mg-ZSM-5 is made in 120 DEG C of dry 4h, 500 DEG C of roasting 4h.5g catalyst precarsor is placed in In continuous fixed bed reactor, catalyst precarsor is handled using the mixed gas of bromomethane and nitrogen, bromomethane volume is dense Degree is 80%, and treatment conditions are 250 DEG C, 0.3MPa(absolute pressure), 300h^-1, time 2h, obtained bromomethane preparing isobutene catalyst, note For D-2.Catalyst weight group is obtained as ZnBr₂Weight content is 30%, ZnO weight content in terms of oxide in terms of bromide It is 4%, 450 DEG C or less total acid contents are 0.89mmol/g in catalyst, and 250 DEG C -350 DEG C of acid content accounts for 450 DEG C or less total acid contents 65.7%.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 70%, and reaction temperature is 230 DEG C, reaction pressure For 2MPa(absolute pressure), air speed 200h^-1.After stable reaction one hour, sampling analysis.Reaction result is shown in Table 1.

Comparative example 3

30g Hydrogen ZSM-5 molecular sieve (silica alumina ratio 100) carrier is weighed, the NaOH water that 450mL concentration is 1 mol/L is dipped in In solution, 1h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h；The sample after drying, which is dipped in 900mL concentration, again is In the aqueous hydrochloric acid solution of 1.5mol/L, 2h is stirred at 50 DEG C, is then separated by solid-liquid separation, 100 DEG C of dry 9h, 550 DEG C of roasting 6h.It weighs Sample after 20g roasting is added in the magnesium nitrate solution that 50mL concentration is 0.5mol/L, stands 12h, then dry at 120 DEG C Dry 12h obtains the modified zsm-5 zeolite that content of magnesium is 3% in 550 DEG C of roasting 6h.

It weighs appropriate zinc bromide to be dissolved in deionized water, above-mentioned modified ZSM-5 molecule is carried on using equi-volume impregnating Carrier, the dry 4h of 80 DEG C of nitrogen atmospheres are sieved, 500 DEG C of nitrogen atmospheres roast 4h, catalyst Z nBr is made₂/ Mg-ZSM-5, is denoted as D- 3.Catalyst weight group is obtained as ZnBr₂Weight content is 30% in terms of bromide, and 450 DEG C or less total acid contents are in catalyst 0.97mmol/g, 250 DEG C -350 DEG C of acid content account for the 75.3% of 450 DEG C or less total acid contents.

Bromomethane conversion preparing isobutene reaction carries out in continuous flow actuating miniature fixed bed reactors.Catalyst loading 5g, Unstripped gas is bromomethane and nitrogen mixed gas, and wherein bromomethane volume content is 70%, and reaction temperature is 230 DEG C, reaction pressure For 2MPa(absolute pressure), air speed 200h^-1.Before being passed through unstripped gas, catalyst activates under the mixed atmosphere of hydrogen, mixed gas Middle hydrogen volume content is 80%, and reducing condition is 450 DEG C, 0.3MPa(absolute pressure), 800h^-1, recovery time 4h is catalyzed after reduction Content of halogen in agent is restore total halogen content in procatalyst 93.71%.After stable reaction one hour, sampling analysis.Instead 1 should be the results are shown in Table.

1 catalyst reaction performance of table

Claims (22)

1. a kind of using modified zsm-5 zeolite as the preparation method of the preparing isobutene catalyst of carrier, it is characterised in that: including such as Lower process: (1) Hydrogen ZSM-5 molecular sieve carrier is respectively subjected to aqueous slkali, acid solution and magnesium salt solution impregnation；(2) will In zinc oxide is introduced to that treated Hydrogen ZSM-5 molecular sieve carrier；(3) to the Hydrogen ZSM-5 molecular sieve after introducing zinc oxide Carrier carries out bromination processing, and bromination zinc oxide weight content into catalyst is 0.5%-20%, and zinc bromide weight content is 10%- 50%。

2. according to the method described in claim 1, it is characterized by: impregnation process is as follows in step (1): by Hydrogen ZSM-5 molecular sieve carrier is added in aqueous slkali by the liquid-solid ratio of 5mL/g-25mL/g, in room temperature to 80 DEG C of stirring 0.5h-1.5h, It is separated by solid-liquid separation, obtained solid is in 80 DEG C -120 DEG C dry 6h-12h；It is solid by the liquid of 10mL/g-50mL/g by the sample after drying Than being added in acid solution, in 30 DEG C to 70 DEG C stirring 1h-3h, separation of solid and liquid, obtained solid in 80 DEG C -120 DEG C dry 6h-12h, Then at 450 DEG C of -650 DEG C of roasting 4h-8h；Roasting sample is added in magnesium salt solution, is added by every gram of ZSM-5 molecular sieve The ratio mixing for entering 1mL-5mL magnesium salt solution, stands 4h-12h, 80 DEG C -120 DEG C dry 6h-12h, then at 450 DEG C of -650 DEG C of roastings 4h-8h is burnt to get modified zsm-5 zeolite carrier.

3. according to the method described in claim 1, it is characterized by: aqueous slkali is NaOH, KOH or Na₂CO₃One in aqueous solution Kind is several, and the concentration of aqueous slkali is 0.1mol/L-2mol/L；Acid solution be one of hydrochloric acid, nitric acid or sulfuric acid solution or Several, the concentration of acid solution is 0.1mol/L-5mol/L；In obtained modified zsm-5 zeolite carrier, magnesium is carrying based on the element Weight content in body is 0.5%-10%.

4. according to the method described in claim 1, it is characterized by: zinc oxide is introduced to modified hydrogen ZSM-5 in step (2) The method of molecular sieve carrier uses impregnation method.

5. according to the method described in claim 4, it is characterized by: being impregnated using zinc solution Hydrogen ZSM-5 points modified Son sieve carrier, obtains bromomethane preparing isobutene catalyst precarsor after drying, roasting.

6. according to the method described in claim 5, it is characterized by: the drying condition is, -150 DEG C of temperature 60 C；Time is 1h-24h；The roasting condition is 200 DEG C -800 DEG C of temperature；Time is 1h-24h；Zinc salt is nitrate, hydrochloride, acetic acid One or more of salt, citrate.

7. according to the method described in claim 1, it is characterized by: the bromination processing refers to be contained using gas phase in step (3) Bromine compounds handles the sample of load zinc oxide.

8. according to the method described in claim 7, it is characterized by: bromine-containing compound refers to bromomethane, methylene bromide, tribromo first One or more of alkane.

9. according to the method described in claim 1, it is characterized by: in step (3), using gas phase bromine-containing compound and indifferent gas The mixed gas of body carries out bromination processing, and bromomethane volumetric concentration is not less than 20%.

10. according to the method described in claim 1, it is characterized by: specific bromination process is as follows: the sample of zinc oxide will be loaded It is placed in continuous fixed bed reactor, 150 DEG C -400 DEG C is warming up under inert atmosphere and is passed through gas phase bromine-containing compound gas, Gas space velocity is 50h^-1-1000 h^-1；System pressure is 0.1MPa-0.5MPa when processing, and the processing time is 0.5h-8h.

11. the catalyst of claims 1 to 10 either method preparation, it is characterised in that: the catalyst is by zinc oxide, zinc bromide And modified zsm-5 zeolite carrier composition, based on the weight content of catalyst, zinc oxide content 0.5%-20%, zinc bromide contains Amount be 10%-50%, modified zsm-5 zeolite vector contg be 40%-85%, ZSM-5 molecular sieve carrier silica alumina ratio be 20 ~ 200。

12. catalyst according to claim 11, it is characterised in that: use NH₃In the catalyst that-TPD is measured 450 DEG C with Lower total acid content is 0.5mmol/g-1.3mmol/g, and 250 DEG C -350 DEG C of acid content accounts for the 20%-90% of 450 DEG C or less total acid contents.

13. application of the catalyst described in claim 11 in preparing isobutene, it is characterised in that: including carrying out hydrogen to catalyst Reduction activation makes the content of halogen in catalyst restore the 20%-90% of total halogen content in procatalyst, then makes halogenated first Catalyst after alkane is activated with above-mentioned hydrogen reducing contacts, to prepare isobutene.

14. application according to claim 13, it is characterised in that: the condition of the hydrogen reducing activation makes in catalyst Content of halogen be restore procatalyst in total halogen content 30%-80%.

15. application according to claim 13, it is characterised in that: the mode of the hydrogen reducing activation is included in indifferent gas By catalyzer temperature-elevating to 300 DEG C -600 DEG C under atmosphere；Then passing to air speed is 200h^-1-2000h^-1Hydrogen or hydrogen and indifferent gas The mixed gas of body keeps 2h-16h in 0.1MPa-0.5MPa, and hydrogen volume percentage composition is 10%-95% in mixed gas.

16. application according to claim 15, it is characterised in that: be warming up to 350 DEG C -550 DEG C；Then passing to air speed is 500h^-1-1000h^-1Hydrogen or hydrogen and inert gas mixed gas, keep 4h-8h in 0.1MPa-0.3MPa, it is described mixed Closing hydrogen volume percentage composition in gas is 30%-90%.

17. application according to claim 13, it is characterised in that: the halide is a halide, dihalo first One of alkane, three halides are a variety of.

18. application according to claim 13, it is characterised in that: the condition of the contact include reaction temperature be 150 DEG C- 350℃；Reaction pressure is 0.1MPa-5MPa；Air speed is 50h^-1-1000h^-1。

19. application according to claim 18, 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。

20. application according to claim 13, it is characterised in that: including under inert atmosphere by catalyzer temperature-elevating to 300 DEG C- 600℃；Then passing to air speed is 200h^-1-2000h^-1Hydrogen or hydrogen and inert gas mixed gas, in 0.1MPa- After 0.5MPa handles 2h-16h, it is down to reaction temperature and is passed through halide and reacted, hydrogen volume percentage in the gaseous mixture Content is 10%-95%%.

21. application according to claim 13, it is characterised in that: raw material is the gaseous mixture of halide and inert gas Body, the volumetric concentration of halide is 10%-90% in mixed gas.

22. application according to claim 13, it is characterised in that: the reaction of halide preparing isobutene is in fixed bed, fluidisation It is carried out in bed, moving bed, slurry bed system or fluidized bed reactor.