CN103833047B

CN103833047B - SAPO-5/SAPO-18/SAPO-34 symbiotic composite molecular sieve and preparation method for same

Info

Publication number: CN103833047B
Application number: CN201410121464.8A
Authority: CN
Inventors: 邢爱华; 张新锋; 冯琦瑶; 石玉林; 王理
Original assignee: Shenhua Group Corp Ltd; National Institute of Clean and Low Carbon Energy
Current assignee: China Energy Investment Corp Ltd; National Institute of Clean and Low Carbon Energy
Priority date: 2014-03-28
Filing date: 2014-03-28
Publication date: 2015-06-24
Anticipated expiration: 2034-03-28
Also published as: CN103833047A

Abstract

The invention discloses a composite molecular sieve, which is obtained by the symbiosis of an SAPO-5 (silico-alumino-phosphate-5) molecular sieve, an SAPO-18 molecular sieve and an SAPO-34 molecular sieve. The composite molecular sieve is characterized in that the molar ratio of raw materials for preparing the composite molecular sieve, namely R:SiO2:Al2O3:P2O5:H2O is (1.2-1.8):(0.2-0.8):1:(0.9-1.25):(40-80), wherein R represents a triethylamine or N,N-diisopropylethylamine template agent. A catalyst which is prepared from the composite molecular sieve and is used for preparing light olefin from an organic oxygen-containing compound is high in catalytic activity and propene and butene selectivity and long in service life.

Description

A kind of SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen and preparation method thereof

Technical field

The present invention relates to a kind of composite molecular screen by SAPO-5 molecular sieve, SAPO-18 molecular sieve and the symbiosis of SAPO-34 molecular sieve and preparation method thereof, this composite molecular screen for the preparation of the catalyzer of organic oxygen-containing compound producing light olefins, and significantly can improve the productive rate of propylene and butylene.

Background technology

Petro-technology route produces the method for low-carbon alkene as an alternative, and the technique of organic oxygen-containing compound, such as methyl alcohol and/or dimethyl ether low-carbon alkene is day by day subject to people and pays close attention to.This technique uses molecular sieve catalyst usually.The molecular sieve catalyst of organic oxygen-containing compound producing light olefins is proposed and the ZSM-5 molecular sieve adopted by Mobil company of the U.S. the earliest, but this molecular sieve pore passage is comparatively large, surface acidity is comparatively strong, the selectivity of ethene and/or propylene is also lower, simultaneously, also can generate the by product such as aromatic hydrocarbons and paraffin, so people begin one's study and develop the more practical molecular sieve catalyst of other organic oxygen-containing compound producing light olefins.

Afterwards, people develop again the catalytic active component of molecular sieve as organic oxygen-containing compound producing light olefins catalyzer in various little duct gradually, such as T zeolite molecular sieve, erionite molecular sieve, chabazite (CHA) molecular sieve, but these catalyzer in use show easy coking and the fast feature of deactivation rate, and these shortcomings cause their further genralrlization and application to be restricted.

USP4499327 and US5095163 discloses the Catalysts and its preparation method of a kind of aluminosilicophosphate (SAPO) as methanol-to-olefins (MTO).Thereafter, numerous document is also had to disclose multiple SAPO family molecular sieves, especially SAPO-34 molecular sieve as the active ingredient of the catalyzer of preparing light olefins from methanol.

Such as, CN102557073A discloses a kind of preparation method of SAPO-34 molecular sieve, the method is by the order by merging of optimizing materials and the state of Primogel, take two sections of ways heating up and control temperature rise rate, improve the degree of crystallinity of synthesized SAPO-34 molecular sieve, effectively controlling the strength of acid of SAPO-34 molecular sieve and sour density, making it for having higher ethene and/or Propylene Selectivity during methanol to olefins reaction.

CN101767800B also discloses a kind of preparation method of SAPO-34 molecular sieve, and the method improves the relative crystallinity of SAPO-34 molecular sieve and the selectivity of light olefin in MTO reaction by adopting fluorochemical as auxiliary template agent.

Usually, silicon aluminium phosphate (SAPO) molecular sieve that can be used as the catalytic active component of organic oxygen-containing compound producing light olefins catalyzer has SAPO-5, SAPO-11, SAPO-17, SAPO-18 and/or SAPO-34 molecular sieve etc., and wherein general with SAPO-34 molecular sieve, although above-mentioned SAPO Series Molecules sieve is all by [SiO ₄], [AlO ₄] and [PO ₄] tetrahedron element is formed, but their microcosmic crystalline structure there are differences, and such as, the crystalline structure of SAPO-34 molecular sieve is chabazite (CHA) type; And the crystalline structure of SAPO-18 molecular sieve is AEI structure, although its AEI structure is the microcosmic pore passage structure similar with CHA structure.

In fact, the AEI structure elementary cell of SAPO-18 molecular sieve is two six-ring and tetra-atomic ring, and its orifice diameter is 0.43 nanometer, and therefore, it belongs to pore zeolite structure.Experiment shows: as the catalytic active component of organic oxygen-containing compound producing light olefins catalyzer, and SAPO-18 molecular sieve has the work-ing life more superior than SAPO-34 molecular sieve.

In reaction for preparing light olefins from methanol, though SAPO-34 shows ethene and the more excellent product selectivity of propylene, but in reaction process, easily form carbon distribution fast and make rapid catalyst deactivation.And the sour position of SAPO-18 molecular sieve B is less, medium tenacity acid site is weak compared with SAPO-34 molecular sieve, and therefore SAPO-34/SAPO-18 composite molecular screen can reduce carbon deposition rate, the life-span of extending catalyst.

CN102372291A discloses composite molecular screen of a kind of SAPO-18/SAPO-34 symbiosis and preparation method thereof, which solves the problem that existing molecular sieve bore diameter is single, catalytic activity is not high.The method is by adopting the template being applicable to SAPO-18 and SAPO-34 growth simultaneously, control the proportioning raw materials be applicable in the crystallization liquid of SAPO-18 and SAPO-34 growth, the crystallization temperature of SAPO-18 and the SAPO-34 growth involved by adjustment, synthesizes the composite molecular screen of SAPO-18 and SAPO-34 symbiosis under hydrothermal conditions.When above-mentioned composite molecular screen is used for methanol to olefins reaction, ethene and propene yield can reach more than 80%, and the life-span can reach 120 minutes.

Usually, micro porous molecular sieve has regular microvoid structure, suitable acidity, good hydrothermal stability, but micro porous molecular sieve also can generate comparatively macromole in reaction process, and narrow duct causes macromole product mass transfer diffusional resistance excessive, product is out comparatively difficult from duct internal divergence, thus, exacerbate the coking of molecular sieve catalyst duct, and cause catalyst deactivation.

For methanol to olefins reaction, molecular sieve inside diffusional resistance have impact on the rate of diffusion of product; Generate target product-alkene in the cage of molecular sieve after, alkene is in the process of external diffusion, acidic site in molecular sieve can there is further oligomeric, condensation, hydrogen transfer reactions, cause catalyst carbon deposit or generate by product alkane, this reduces the selectivity of object product-alkene, and cause catalyzer coking and deactivation.

Another kind of SAPO Series Molecules sieve is SAPO-5 molecular sieve, and it belongs to AFI type molecular sieve, the one-dimensional linear of the twelve-ring that its skeleton is alternately made up of two tetra-atomic rings and six-ring and not cross one another channel system, and it belongs to macroporous type micro porous molecular sieve.If introduce appropriate wide-aperture SAPO-5 molecular sieve in the SAPO-34 molecular sieve of small-bore, will likely improve the performance of SAPO-34 molecular sieve and catalyzer thereof, and overcome the shortcoming of above-mentioned SAPO-34 molecular sieve catalyst.

CN102372290A discloses a kind of synthetic method of SAPO-5 and SAPO-34 coexisting molecular sieve, and described method is by optimizing material proportion, and obtain SAPO-5 and SAPO-34 coexisting molecular sieve, wherein, material proportion is: Al ₂o ₃: P ₂o ₅: SiO ₂: R:H ₂o mol ratio is 1.0:(0.2-2.0): (0.1-2.0): (0.5-2.5): (20-100), wherein, R represents template.

CN102049294B discloses molecular sieve of a kind of composite structure and its preparation method and application, in fact, it is a kind of AlPO-5/SAPO-34 composite molecular screen, in the preparation process of this composite molecular screen, SAPO-34 molecular sieve is incorporated in the raw material of preparation AlPO-5 molecular sieve and goes, the composite molecular screen that final formation is synthesized by AlPO-5 and SAPO-34.When this composite molecular screen is used for organic oxygen-containing compound reaction for preparing light olefins, because AlPO-5 has macropore and/or the meso-hole structure of some amount, the work-ing life of molecular sieve catalyst is extended to some extent, and adds the selectivity of propylene.But in above-mentioned AlPO-5/SAPO-34 composite molecular screen, AlPO-5 and SAPO-34 is not obviously symbiosis.

Above patent documentation is introduced with for referencial use in full at this.

Traditional MTO technology is product for the purpose of ethene and/or propylene mainly, butylene and C ₅the above component of+hydrocarbon is only by product.But C ₄hydrocarbon is the important raw materials for production of petrochemical complex and organic chemical industry, and its purposes comes into one's own day by day.C ₄olefin downstream derivative is wide in variety, and market potential is large.

The 2-propyl enanthol produced by butylene is the main raw material producing DPHP, and China in the DPHP wide market coming years, and has good economic benefit.Develop extraordinary polyolefine and specialty elastomer, as polybutene, polyisobutene, styrene-butadiene rubber(SBR) with take iso-butylene as development of raw materials MTBE, ETBE or produce through iso-butylene-MTBE-isooctene the requirement that octane-iso alkylate oil all meets " derived product is based on general synthetic materials " proposed in country 12 planning, products obtained therefrom differentiation degree is low, and added value is high, by force functional.

Improve the ratio of olefin downstream high-end product, develop and produce the PP Pipe Compound such as extraordinary polyethylene and polypropylene, it is industry development guilding policy that polyisoprene rubber, rare earth polybutadiene rubber, quickening realize the replacement of alkene industrial product structure adjustment and escalation.Now, C ₄hydrocarbon resource is mainly derived from the by product of refining of petroleum, preparing ethylene by steam cracking and methanol-to-olefins (MTO) technique, so, C ₄hydrocarbon resource need further expand.

The C of conventional methanol alkene (MTO) technique using SAPO-34 molecular sieve catalyst only by-product about 5.5% (to methyl alcohol) ₄hydrocarbon mixture, this C ₄in hydrocarbon mixture, 1,3-butadiene, iso-butylene content are lower, and main ingredient is butene-1 and butene-2, and they account for 90%.(see " olefin hydrocarbon making by coal and the derived product market requirement and Analysis on Processing Technology ", Wu Xiuzhang).For realizing C ₄hydrocarbon utilizes and reaches scale and benefit, need improve C ₄hydrocarbon output, like this, just urgently exploitation has high C ₄the catalyzer of olefine selective.

The present invention is devoted to solve above-mentioned technical barrier, and strives developing a kind of SAPO-5/SAPO-18/SAPO-34 composite molecular screen for the preparation of organic oxygen-containing compound alkene catalyst in work-ing life simultaneously with good catalytic activity, higher propylene and/or butylene selectivity and excellence.

Summary of the invention

According to a first aspect of the invention, provide a kind of composite molecular screen, formed by SAPO-5 molecular sieve, SAPO-18 molecular sieve and the symbiosis of SAPO-34 molecular sieve, it is characterized in that: prepare this composite molecular screen raw material used and meet following ratio: R:SiO ₂: Al ₂o ₃: P ₂o ₅: H ₂o mol ratio is (1.2-1.8): (0.2-0.8): 1:(0.9-1.25): (40-80), wherein, R represents triethylamine or N, N-diisopropyl ethyl amine template.

Preferably, prepare this composite molecular screen raw material used and meet following ratio further: Et ₃n:SiO ₂: Al ₂o ₃: P ₂o ₅: H ₂o mol ratio is 1.5:(0.3,0.4 or 0.6): 1:1:50.

Usually, in the raw material of the above-mentioned composite molecular screen of preparation, SiO ₂come from tetraethoxy, silicon sol, white carbon black, water glass, white carbon black or their arbitrary mixtures; Al ₂o ₃come from pseudo-boehmite, pseudobochmite, Alumina gel, aluminum isopropylate, aluminium salt, aluminate, activated alumina or their arbitrary mixtures; P ₂o ₅come from phosphoric acid, phosphorous acid, phosphoric acid salt and/or phosphorous oxides.

Preferably, by regulating triethylamine in above-mentioned composite molecular screen raw material or N, N-diisopropyl ethyl amine template and SiO ₂consumption, adjusts SAPO-5 molecular sieve, SAPO-18 molecular sieve and the relative content of SAPO-34 molecular sieve in composite molecular screen, and then adjusts pore passage structure distribution and the acidity of described composite molecular screen.

According to a second aspect of the invention, provide a kind of preparation method of above-mentioned composite molecular screen, it comprises the following steps successively:

(1) in proportion by aluminium source, phosphorus source, silicon source, triethylamine or N, N-diisopropyl ethyl amine template and water mix at the temperature of 20 DEG C-90 DEG C, control the rate of addition of each step raw material, obtain comprising aluminium source, phosphorus source, silicon source, triethylamine template or N, the mixing solutions of N-diisopropyl ethyl amine and water, in above-mentioned mixing solutions, triethylamine or N, N-diisopropyl ethyl amine template: SiO ₂: Al ₂o ₃: P ₂o ₅: H ₂the mol ratio of O is (1.2-1.8): (0.2-0.8): 1:(0.9-1.25): (40-80); (2) described mixing solutions is stirred until each component disperses of mixing solutions is even, mixing solutions described in ageing subsequently, until form gel mixture; (3) gel mixture is put into 170 DEG C of-210 DEG C of reactors and carry out Hydrothermal Synthesis crystallization 24-80 hour; (4) the solid crystal thing that crystallization is formed is separated, drier described solid crystal thing, obtain the former powder of composite molecular screen; (5) the former powder 2-8 hour of the above-mentioned composite molecular screen of roasting at 450-650 DEG C, removing triethylamine wherein or N, N-diisopropyl ethyl amine template, obtain by the composite molecular screen of SAPO-5 molecular sieve, SAPO-18 molecular sieve and the symbiosis of SAPO-34 molecular sieve.

In above-mentioned preparation method, preferably, described silicon source is tetraethoxy, silicon sol, white carbon black, water glass, white carbon black or their arbitrary mixtures; Described aluminium source is pseudo-boehmite, pseudobochmite, Alumina gel, aluminum isopropylate, aluminium salt, aluminate, activated alumina or their arbitrary mixtures; Described phosphorus source is phosphoric acid, phosphorous acid, phosphoric acid salt and/or phosphorous oxides.

Preferably, in above-mentioned preparation method, in step (4), the solid crystal thing that described separation crystallization is formed refers to: the solid crystal thing that centrifuging is formed, to remove the crystallisate mother liquor that Hydrothermal Synthesis crystallization produces, with solid crystal thing described in deionized water wash at least one times, then solid crystal thing described in centrifuging is at least one times.

Preferably, in above-mentioned preparation method, the described mixing solutions in step (1) is prepared by the following method: aluminium source, phosphorus source and silicon source mix with water by (1) respectively, forms aluminium source solution, phosphorus source solution and silicon source solution; (2) lentamente aluminium source solution is added drop-wise in the solution of phosphorus source, or phosphorus source solution is added drop-wise in the solution of aluminium source, form the mixing solutions in aluminium source and phosphorus source; (3) lentamente silicon source solution is added drop-wise in the mixing solutions in aluminium source and phosphorus source, or the mixing solutions in aluminium source and phosphorus source is added drop-wise in the solution of silicon source, form the mixing solutions in aluminium source, phosphorus source and silicon source; (4) in the mixing solutions in described aluminium source, phosphorus source and silicon source, add triethylamine or N, N-diisopropyl ethyl amine template again, thus form the mixing solutions comprising aluminium source, phosphorus source, silicon source, triethylamine or N, N-diisopropyl ethyl amine template and water.

According to a third aspect of the invention we, provide a kind of catalyzer by organic oxygen-containing compound producing light olefins, the catalytic active component of described catalyzer is above-mentioned composite molecular screen or the composite molecular screen prepared by aforesaid method.

Preferably, above-mentioned organic oxygen-containing compound is methyl alcohol and/or dme; Described low-carbon alkene is ethene, propylene and/or butylene.

Accompanying drawing explanation

Fig. 1 is scanning electron microscope (SEM) photo of SAPO-5/SAPO-18/SAPO-34 composite molecular screen of the present invention.

Fig. 2 is the X-ray diffracting spectrum of SAPO-5/SAPO-18/SAPO-34 composite molecular screen in embodiment 1.

Fig. 3 is the X-ray diffracting spectrum of SAPO-5/SAPO-18/SAPO-34 composite molecular screen in embodiment 2.

The X-ray diffracting spectrum of SAPO-5/SAPO-18/SAPO-34 composite molecular screen in Fig. 4 embodiment 3.

Fig. 5 be in embodiment 1 SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen as reaction product selectivity each during catalyzer and the relation curve in reaction times.

Fig. 6 be in embodiment 3 SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen C as reaction product selectivity each during catalyzer and the relation curve in reaction times.

Fig. 7 be in embodiment 4 SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen D as reaction product selectivity each during catalyzer and the relation curve in reaction times.

Fig. 8 be in comparative example 1-1 SAPO-5 molecular sieve as reaction product selectivity each during catalyzer and the relation curve in reaction times.

Fig. 9 be in comparative example 1-3 SAPO-34 molecular sieve as reaction product selectivity each during catalyzer and the relation curve in reaction times.

Figure 10 be in comparative example 1-2 SAPO-5/SAPO-34 composite molecular screen as reaction product selectivity each during catalyzer and the relation curve in reaction times.

Embodiment

By being further explained in detail the present invention below with reference to the description of embodiment and accompanying drawing, but below describe only for enabling general technical staff of the technical field of the invention clearly understand principle of the present invention and marrow, and do not mean that any type of restriction is carried out to the present invention.

SAPO-5/SAPO-18/SAPO-34 composite molecular screen of the present invention is by having the SAPO-5 lamella molecular sieve of twelve-ring pore passage structure and the SAPO-18 lamella molecular sieve with octatomic ring pore passage structure and the cubes SAPO-34 symbiosis with the octatomic ring pore passage structure selecting by force shape forms, twelve-ring SAPO-5 molecular sieve is because having certain catalytic cracking reaction activity in acid, its macroporous structure eliminates the shape selectivity to the butene product comprising iso-butylene, can make to react rich and produce butylene; Octatomic ring SAPO-18 acidic zeolite is moderate, and it is when catalysis organic oxygen-containing compound reaction for preparing light olefins, and catalytic activity is higher, and due to medium tenacity acid site acidity more weak, stability is better, and catalyst carbon deposit deactivation rate prepared therefrom is slow; The octatomic ring SAPO-34 molecular sieve selecting by force shape has suitable Bronsted acidity and pore passage structure, larger specific surface area, good absorption property and good hydrothermal stability, and it presents good catalytic activity and olefin product selectivity to organic oxygen-containing compound olefine reaction.

The present invention strives that one of technical problem underlying solved is under the prerequisite guaranteeing high Propylene Selectivity, improve the selectivity of butylene in organic oxygen-containing compound olefine reaction, and adopt and to control in synthesized gel rubber triethylamine or N, N-diisopropyl ethyl amine template and SiO ₂content, optimizing materials proportioning and order by merging, regulation and control crystallization time series of steps, successfully synthesis has the lamellar of acid micropore and macropore and the composite molecular sieves of cubic once.The complex type molecular sieve of preparation method's synthesis of the present invention has good diffusion flux and suitable acidity, when using it for organic oxygen-containing chemical combination olefine reaction, has higher propylene and butylene selectivity, is conducive to realizing Coal Chemical Industry C ₄the large-scale production of alkene resource downstream derivative thing.

Above-mentioned SAPO-5/SAPO-18/SAPO-34 composite molecular screen can be used as the catalyzer of catalytic active component for the preparation of organic oxygen-containing compound, particularly reaction for preparing light olefins from methanol.When using the catalyzer of so preparation, the reaction of preparing light olefins from methanol richly can produce propylene and butylene.Preferably, when using above-mentioned catalyzer, in reaction for preparing light olefins from methanol, ethylene selectivity can at about 10-15%, and Propylene Selectivity can at about 35-40%, and butylene selectivity can at about 20-30%; In butylene product, 1-butylene can account for 15-20%, and 2-butylene can account for 46-56%, and iso-butylene can account for 21-37%.

The present inventor is in the process of preparation SAPO-5 molecular sieve, SAPO-34 molecular sieve and SAPO-5/SAPO-34 composite molecular screen, find amazedly: when each proportioning raw materials is in the specified range of a relative narrower, such as, as triethylamine or N, N-diisopropyl ethyl amine template: SiO ₂: Al ₂o ₃: P ₂o ₅: H ₂o mol ratio is (1.2-1.8): (0.2-0.8): 1:(0.9-1.25): time (40-80), what obtain is not SAPO-5 molecular sieve, SAPO-34 molecular sieve or SAPO-5/SAPO-34 composite molecular screen, but SAPO-5/SAPO-18/SAPO-34 three-phase composite molecular sieve.The present inventor, on this basis, completes the present invention through performing creative labour and a large amount of screening operations.

Preferably, the present invention, by the preparation method of the composite molecular screen of SAPO-5/SAPO-18/SAPO-34 molecular sieve symbiosis, comprises the following steps successively:

(1) in proportion by aluminium source, phosphorus source, silicon source, triethylamine or N, N-diisopropyl ethyl amine template and water mix at the temperature of 20 DEG C-90 DEG C, control the rate of addition of each step raw material, obtain comprising aluminium source, phosphorus source, silicon source, triethylamine or N, the mixing solutions of N-diisopropyl ethyl amine template and water, in above-mentioned mixing solutions, triethylamine or N, N-diisopropyl ethyl amine template: SiO ₂: Al ₂o ₃: P ₂o ₅: H ₂the mol ratio of O is (1.2-1.8): (0.2-0.8): 1:(0.9-1.25): (40-80); (2) described mixing solutions is stirred until each component disperses of mixing solutions is even, mixing solutions 2-24 hour described in ageing subsequently, until form gel mixture; (3) gel mixture is put into 170 DEG C of-210 DEG C of reactors and carry out Hydrothermal Synthesis crystallization 24-80 hour; (4) be separated the solid crystal thing that formed of crystallization, then at 80 DEG C-120 DEG C dry described solid crystal thing 2-12 hour, obtain the former powder of composite molecular screen; (5) the former powder 2-8 hour of the above-mentioned composite molecular screen of roasting at 450-650 DEG C, removing triethylamine wherein or N, N-diisopropyl ethyl amine template, obtain by the composite molecular screen of SAPO-5 molecular sieve, SAPO-18 molecular sieve and the symbiosis of SAPO-34 molecular sieve.

Usually, in above-mentioned steps (5), carrying out roasting to the former powder of described composite molecular screen is to remove template, and preferably, maturing temperature is 450-650 DEG C, is more preferably 500-600 DEG C; Preferably, roasting time is 2-8 hour, is more preferably 3-6 hour.

Preferably, the preparation method of the organic oxygen-containing compound producing light olefins catalyzer that the present invention is catalytic active component with above-mentioned SAPO-5/SAPO-18/SAPO-34 composite molecular screen, comprises the following steps successively:

(1) above-mentioned SAPO-5/SAPO-18/SAPO-34 composite molecular screen, molding adhesive, additive, peptizing agent are mixed with water, each self-forming solution or slurries.When each self-forming solution or slurries, can be auxiliary in heating or stir, to promote to mix, but water deionized water; (2) SAPO-5/SAPO-18/SAPO-34 composite molecular screen slurries are mixed with molding adhesive solution, additive slurries, peptizing agent solution successively, final formation Homogeneous phase mixing slurries, and leave standstill or ageing; (3) the mixed slurries after standing or ageing are carried out spray drying forming, obtain shaped granule, then through roasting, thus, obtain described SAPO-5/SAPO-18/SAPO-34 composite molecular sieve catalyst.

Wherein, the weight ratio of described SAPO-5/SAPO-18/SAPO-34 composite molecular screen, molding adhesive, additive, peptizing agent is preferably 1:0.1-0.6:0.5-1.5:0.01-0.25.

In above-mentioned steps (1), the weight ratio of each material and water can respectively: SAPO-5/SAPO-18/SAPO-34 composite molecular screen: water=1:0.2-5.0, is preferably 1:0.5-3.0; Binding agent: water=1:0.5-5.0, is preferably 1:1.0-3.0; Additive: water=1:0.5-5.0, is preferably 1:1.0-3.0; Peptizing agent: water=1:0.2-5.0, is preferably 1:0.5-4.5.Preferably, the mixing time of each solution, slurries or mixed solution is 5-60 minute, is more preferably 15-30 minute.

In a more preferred, described molding adhesive is pseudo-boehmite; Described additive is kaolin (stone); Described peptizing agent is dust technology, and based on the gross weight of acid solution, acid concentration is 5-45%, preferred 10-40%.

In method for preparing catalyst of the present invention, the mean particle size (diameter) of above-mentioned SAPO-5/SAPO-18/SAPO-34 composite molecular screen, binding agent, additive, preferably more than 75 microns, is more preferably 0.1-20 micron.

In a preferred embodiment, the weight ratio of described SAPO-5/SAPO-18/SAPO-34 composite molecular screen, binding agent, additive, peptizing agent is 1:0.15-0.55:0.65-1.45:0.05-0.20.

In above-mentioned steps (2), preferably, first described SAPO-5/SAPO-18/SAPO-34 composite molecular screen slurries mix with molding adhesive solution, form the first mixed solution; Then, this first mixed solution mixes with additive slurries, forms the second mixed solution; This second mixed solution mixes with peptizing agent solution again, forms the third mixed solution, i.e. mixed serum, and based on slurries gross weight, its solid content is 8-35%, is preferably 10-30%, is more preferably 15-25%.Therefore, should be understood that: " successively " mixing adds follow-up blending ingredients in the mixed solution of back formation, thus formed containing more multi-component mixed solution.

In above-mentioned steps (2), the mixing time of each mixing step is approximately 5-80 minute, is preferably 7-60 minute, is more preferably 10-45 minute.

Preferably, in above-mentioned steps (2), strong stirring mixing is carried out to the mixed serum comprising SAPO-5/SAPO-18/SAPO-34 composite molecular screen, molding adhesive, additive, peptizing agent and water, to form Homogeneous phase mixing slurries.Preferably, strong stirring mixing colloidal mill and/or high-shear boxshear apparatus carry out.

Such as, the time of above-mentioned strong stirring mixing is 10-80 minute, is particularly preferably 30-70 minute, most preferably is 35-60 minute; Preferably, colloidal mill and/or high-shear boxshear apparatus rotating speed are 4000-12000 rev/min, are more preferably 4500-10000 rev/min, are particularly preferably 5000-8000 rev/min.

Usually, the standing or Aging Temperature of above-mentioned Homogeneous phase mixing slurries is 10-80 DEG C, is preferably 15-45 DEG C, most preferably is 20-40 DEG C.Preferably, standing or digestion time is 1-48 hour, is more preferably 12-24 hour.

Based on slurries gross weight, to leave standstill or the solid content of Homogeneous phase mixing slurries after ageing is 8-35%, be preferably 10-30%, more preferably 15-25%.

Preferably, the operational condition of above-mentioned Homogeneous phase mixing slurries spray drying forming is as follows: spray-dryer temperature in: 250-400 DEG C, temperature out: 100-200 DEG C.Shaped granule particle diameter: 40-100 micron, preferred 45-90 micron.

Usually, the maturing temperature of shaped granule is 450-650 DEG C, is more preferably 500-600 DEG C; Roasting time is preferably 2-8 hour, is more preferably 5-hour.The catalyzer formed contains the material from components such as SAPO-5/SAPO-18/SAPO-34 composite molecular screen, molding adhesive, additive and peptizing agents, in butt, each components by weight is: SAPO-5/SAPO-18/SAPO-34 composite molecular screen: molding adhesive: additive: peptizing agent=1:0.1-0.6:0.5-1.5:0.01-0.25, is preferably 1:0.15-0.55:0.65-1.45:0.05-0.20.The mean particle size of final SAPO-5/SAPO-18/SAPO-34 composite molecular sieve catalyst is preferably 60-80 micron.

The present invention's low silicon SAPO-5/SAPO-18/SAPO-34 composite molecular screen and the preferred working conditions of catalyzer as follows: temperature of reaction: 300-500 DEG C, preferred 400-500 DEG C; Reaction pressure: 0-0.5MPa; Methanol quality air speed: 1.0-5.0/ hour; Under this working conditions, methanol conversion is close to 100%; Propylene+butylene yield is between 60-70%; SAPO-5/SAPO-18/SAPO-34 composite molecular screen work-ing life, catalyzer work-ing life of SAPO-5/SAPO-18/SAPO-34 composite molecular screen was more than 2 hours more than 200 minutes.

Embodiment

Embodiment 1: the SAPO-5/SAPO-18/SAPO-34 composite molecular screen of preparation symbiosis

By 12 grams of pseudo-boehmites and 20.0 grams of deionized water mix and blends, form aluminium source solution, be phosphoric acid and 20.0 grams of deionized water mix and blends of 85 % by weight by 11.89 grams of concentration, form phosphorus source solution, be 40 % by weight silicon sol and 4.5 grams of deionized water mix and blends by 4.86 grams of concentration, form silicon source solution.

Then, phosphorus source solution is slowly added drop-wise in the solution of aluminium source, forms the mixing solutions in aluminium source and phosphorus source, uniform stirring 1 hour, again silicon source solution is joined in the mixing solutions in aluminium source and phosphorus source, uniform stirring 1 hour, form the mixing solutions in silicon source, aluminium source and phosphorus source.Afterwards, in above-mentioned mixing solutions, add 7.8 grams of triethylamine template, then add 7 grams of deionized waters, ageing 2 hours under whipped state, thus, form gel.

In above process, triethylamine template: SiO in mixing solutions ₂: Al ₂o ₃: P ₂o ₅: H ₂the mol ratio of O is 1.5:0.6:1:1:50.

It is in the stainless steel crystallization still of tetrafluoroethylene (teflon) that the gel formed after above-mentioned ageing is loaded inner bag, carries out Hydrothermal Synthesis crystallization 48 hours under 200oC.After the cooling of crystallization still, solid crystallized product is through deionized water centrifuge washing and filtration, after being 200 below μ S/cm to scavenging solution specific conductivity, again at 120 DEG C by dry 8 hours of solid crystallized product, weigh, obtain the former powder of SAPO-5/SAPO-18/SAPO-34 composite molecular screen.

Finally, the former powder of the above-mentioned composite molecular screen of roasting 5 hours in air atmosphere and under 600oC, obtain SAPO-5/SAPO-18/SAPO-34 composite molecular screen, this composite molecular screen is marked as molecular sieve-4 A.

Comparative example 1-1: preparation SAPO-5 molecular sieve

Except becoming except 2.6 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 1, obtain SAPO-5 molecular sieve, this molecular sieve is marked as molecular sieve-4 A-1.

Comparative example 1-2: preparation SAPO-5/SAPO-34 composite molecular screen

Except becoming except 5.2 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 1, obtain SAPO-5/SAPO-34 composite molecular screen, this composite molecular screen is marked as molecular sieve-4 A-2.

Comparative example 1-3: preparation SAPO-34 molecular sieve

Except becoming except 10.4 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 1, obtain SAPO-34 molecular sieve, this molecular sieve is marked as molecular sieve-4 A-3.

Embodiment 2: the SAPO-5/SAPO-18/SAPO-34 composite molecular screen of preparation symbiosis

Except being that the silicon sol consumption of 40 % by weight becomes except 3.24 grams from 4.86 grams by concentration, repeat the process of embodiment 1.

In above process, triethylamine template: SiO in mixing solutions ₂: Al ₂o ₃: P ₂o ₅: H ₂the mol ratio of O is 1.5:0.4:1:1:50.

Obtain SAPO-5/SAPO-18/SAPO-34 composite molecular screen, this composite molecular screen is marked as molecular sieve B.

Comparative example 2-1: preparation SAPO-5 molecular sieve

Except becoming except 2.6 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 2, obtain SAPO-5 molecular sieve, this molecular sieve is marked as molecular sieve B-1.

Comparative example 2-2: preparation SAPO-5/SAPO-34 composite molecular screen

Except becoming except 5.2 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 2, obtain SAPO-5/SAPO-34 composite molecular screen, this composite molecular screen is marked as molecular sieve B-2.

Comparative example 2-3: preparation SAPO-34 molecular sieve

Except becoming except 10.4 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 2, obtain SAPO-34 molecular sieve, this molecular sieve is marked as molecular sieve B-3.

Embodiment 3: the SAPO-5/SAPO-18/SAPO-34 composite molecular screen of preparation symbiosis

Except being that the silicon sol consumption of 40 % by weight becomes except 2.43 grams from 4.86 grams by concentration, repeat the process of embodiment 1.

In above process, triethylamine template: SiO in mixing solutions ₂: Al ₂o ₃: P ₂o ₅: H ₂the mol ratio of O is 1.5:0.3:1:1:50.

Obtain SAPO-5/SAPO-18/SAPO-34 composite molecular screen, this composite molecular screen is marked as molecular sieve C.

Comparative example 3-1: preparation SAPO-5 molecular sieve

Except becoming except 2.6 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 3, obtain SAPO-5 molecular sieve, this molecular sieve is marked as molecular sieve C-1.

Comparative example 3-2: preparation SAPO-5/SAPO-34 composite molecular screen

Except becoming except 5.2 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 3, obtain SAPO-5/SAPO-34 composite molecular screen, this composite molecular screen is marked as molecular sieve C-2.

Comparative example 3-3: preparation SAPO-34 molecular sieve

Except becoming except 10.4 grams by the consumption of triethylamine template from 7.8 grams, repeat the process of embodiment 3, obtain SAPO-34 molecular sieve, this molecular sieve is marked as molecular sieve C-3.

Embodiment 4: the chemically composited molecular sieve of preparation SAPO-5/SAPO-18/SAPO-34

By 17.6 grams of pseudo-boehmites and 35.0 grams of deionized water mix and blends, form aluminium source solution, be phosphoric acid and 35.0 grams of deionized water mix and blends of 85 % by weight by 20.0 grams of concentration, form phosphorus source solution, be silicon sol and 2.5 grams of deionized water mix and blends of 40 % by weight by 2.9 grams of concentration, form silicon source solution.

Then, phosphorus source solution is slowly added drop-wise in the solution of aluminium source, forms the mixing solutions in aluminium source and phosphorus source, uniform stirring 1 hour, again silicon source solution is joined in the mixing solutions in aluminium source and phosphorus source, uniform stirring 1 hour, form the mixing solutions in silicon source, aluminium source and phosphorus source.Afterwards, in above-mentioned mixing solutions, add 14.1 grams of N, N-diisopropyl ethyl amine template, then add 2.6 grams of deionized waters, ageing 2 hours under whipped state, thus, form gel.

In above process, N, N-diisopropyl ethyl amine template: SiO in above-mentioned mixing solutions ₂: Al ₂o ₃: P ₂o ₅: H ₂the mol ratio of O is 1.2:0.2:1:0.95:50.

It is in the stainless steel crystallization still of tetrafluoroethylene (teflon) that the gel formed after above-mentioned ageing is loaded inner bag, carries out Hydrothermal Synthesis crystallization 8 hours, then under 175oC, carry out Hydrothermal Synthesis crystallization 72 hours under 140oC.After the cooling of crystallization still, solid crystallized product is through deionized water centrifuge washing and filtration, after being 200 below μ S/cm to scavenging solution specific conductivity, again at 120 DEG C by dry 8 hours of solid crystallized product, weigh, obtain the former powder of SAPO-5/SAPO-18/SAPO-34 composite molecular screen.

Finally, the former powder of the above-mentioned composite molecular screen of roasting 5 hours in air atmosphere and under 600oC, obtain SAPO-5/SAPO-18/SAPO-34 composite molecular screen, this composite molecular screen is marked as molecular sieve D.

Test case

Test case 1: to the physical property measurement of SAPO-5/SAPO-18/SAPO-34 composite molecular screen of the present invention

(1) X-ray diffraction (XRD) is analyzed

X-ray diffraction (XRD) analysis is carried out to the SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen of the present invention obtained in embodiment 1-3, obtain Fig. 2-4, can find from Fig. 2-4: occurred in the XRD spectra of the SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen obtained in embodiment 1-3 simultaneously SAPO-5 molecular sieve, SAPO-18 molecular sieve and the characteristic diffraction peak of SAPO-34 molecular sieve, this illustrates the chemically composited structure defining above-mentioned three kinds of molecular sieves.

(5) scanning electron microscope (SEM) is analyzed

Fig. 1 is SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen scanning electron microscope (SEM) photo of the present invention of synthesis in embodiment 1, as can be seen from stereoscan photograph: the SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen grain-size of the present invention's synthesis is between 3-10 micron, and it has the laminated structure of typical SAPO-5 molecular sieve and SAPO-18 molecular sieve and the cube structure of SAPO-34 molecular sieve.This also illustrates that SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen of the present invention defines chemically composited structure.

Test case 2: molecular sieve catalytic active is assessed

Adopt fixed bed catalyst evaluating apparatus, catalytic activity and test in work-ing life are carried out to the molecular sieve obtained in embodiment 1-4, comparative example 1-1,1-2,1-3.

After above-mentioned molecular sieve is carried out compressing tablet and fragmentation, it is that 20-40 object part is stand-by as sieve sample that sieve gets granularity.

Take 1.0 grams of above-mentioned sieve samples respectively, with 4 grams of 20-40 object quartz sand Homogeneous phase mixing, and respectively they are put into reactor, nitrogen is passed in 500 DEG C of downhill reaction devices, activate above-mentioned molecular sieve 1 hour, then, temperature of reactor is down to 450 DEG C, reaction pressure is normal pressure, methanol solution as raw material after flow metering pump, mix with carrier gas, and enter in preheating oven under nitrogen-carrier gas is carried, methyl alcohol is gasificated into gas in preheating oven, then, enter in reactor, methyl alcohol carries out the reaction of producing light olefins under the katalysis of above-mentioned molecular sieve.

In above process, nitrogen flow rate: 150 ml/min, methanol weight air speed: 3.0/ hour, reaction product adopts off-line gas-chromatography to carry out composition analysis, wherein, when occurring alcohol and ether in gas chromatogram, illustrate that methanol conversion has not been 100%, now, stop test, start to the time now as molecular sieve work-ing life to react.

In the reaction using composite molecular screen of the present invention (embodiment) and existing molecular sieve (comparative example), measure each product composition corresponding to the differential responses time, by experimental result drafting pattern 5-Figure 10.

Fig. 5 be in embodiment 1 SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen A as reaction product selectivity each during catalyzer and the relation curve in reaction times.As calculated, the mol ratio of SAPO-5 molecular sieve in this composite molecular screen/(SAPO-18+SAPO-34) molecular sieve is 60:40.As can be seen from Figure 5: Propylene Selectivity is very stable, usually maintains about 40%; Ethylene selectivity extends with the reaction times and reduces gradually, finally, is reduced to 18% by 40%; And butylene selectivity increases gradually with reaction times prolongation, finally, be increased to about 30% by 14%.

In the reaction using the invention described above composite molecular screen A, measure butene product and comprise Trans-2-butene, cis-2-butene, 1-butylene and iso-butylene etc.

The invention described above composite molecular screen A(embodiment 1) be suitable as rich catalyzer or catalyst activity component of producing propylene and butylene.

Fig. 6 be in embodiment 3 SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen C as reaction product selectivity each during catalyzer and the relation curve in reaction times.As can be seen from Figure 6: Propylene Selectivity is also more stable, usually maintains about 35-38%; Ethylene selectivity is micro-after extending first increase gradually with the reaction times decline, finally, becomes to about 38% from 33%; And butylene selectivity declines gradually with reaction times prolongation, finally, drop to about 13% by 14%.

The invention described above composite molecular screen C(embodiment 3) be suitable as rich catalyzer or catalyst activity component of producing ethene and propylene.

Fig. 7 be in embodiment 4 SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen D as reaction product selectivity each during catalyzer and the relation curve in reaction times.As can be seen from Figure 7: Propylene Selectivity is relatively stable, usually about 37-35% is maintained; Ethylene selectivity extends with the reaction times and reduces gradually, finally, is reduced to 11% by 24%; And butylene selectivity increases gradually with reaction times prolongation, finally, be increased to about 30% by 19%.These changes are closely similar with Fig. 5.

Using the invention described above composite molecular screen D(embodiment 4) reaction in, measure butene product equally and comprise Trans-2-butene, cis-2-butene, 1-butylene and iso-butylene etc.

The invention described above composite molecular screen D(embodiment 4) be equally also suitable as rich catalyzer or catalyst activity component of producing propylene and butylene.

Fig. 8 be in comparative example 1-1 SAPO-5 molecular sieve-4 A-1 as reaction product selectivity each during catalyzer and the relation curve in reaction times.As can be seen from Figure 8: Propylene Selectivity is micro-after extending first increase gradually with the reaction times decline, but usually maintains between 41-43%; Butylene selectivity is more stable, usually maintains between 18-19%; And ethylene selectivity is minimum, it fluctuates to some extent with reaction times prolongation, but also usually maintains between about 11-13%.Generally speaking, during the SAPO-5 molecular sieve catalytic methanol to olefins reaction synthesized in comparative example 1-1, selectivity of light olefin order is from high to low followed successively by: propylene > butylene > ethene, propylene, butylene, ethylene selectivity are respectively 40%, 20% and about 10%.

Above-mentioned SAPO-5 molecular sieve-4 A-1(comparative example 1-1) be suitable as rich catalyzer or catalyst activity component of producing propylene and butylene, but its butylene selectivity is starkly lower than SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen (composite molecular screen A and D) of the present invention.

Fig. 9 be in comparative example 1-3 SAPO-34 molecular sieve-4 A-3 as reaction product selectivity each during catalyzer and the relation curve in reaction times.As can be seen from Figure 9: the products distribution rule of the SAPO-34 molecular sieve catalytic methanol to olefins reaction synthesized in comparative example 1-3, propylene and butylene selectivity extend with the reaction times and reduce, wherein, Propylene Selectivity is reduced to 33% by 40%, butylene selectivity drops to 8.7% by 15%, ethylene selectivity extends with the reaction times and increases, and is increased to 48% by 36%.

Above-mentioned SAPO-34 molecular sieve-4 A-3(comparative example 1-3) be suitable as rich catalyzer or catalyst activity component of producing ethene and propylene.

Figure 10 be in comparative example 1-2 SAPO-5/SAPO-34 composite molecular screen A-2 as reaction product selectivity each during catalyzer and the relation curve in reaction times.As calculated, in this composite molecular screen, the mol ratio of SAPO-5 molecular sieve/SAPO-34 molecular sieve is 80:20.As can be seen from Figure 10: during the SAPO-5/SAPO-34 plyability molecular sieve catalytic methanol to olefins reaction synthesized in comparative example 1-2, distribution of reaction products is: Propylene Selectivity is more stable, usually maintain between 35%-40%, ethylene selectivity extends with the reaction times and reduces gradually, 13% is reduced to by 29%, butylene selectivity extends with the reaction times and increases gradually, is increased to 22% by 14%.

Above-mentioned SAPO-5/SAPO-34 composite molecular screen A-2(comparative example 1-2) be suitable as rich catalyzer or catalyst activity component of producing propylene and butylene, but its butylene selectivity is starkly lower than SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen (composite molecular screen A and D) of the present invention.

In sum, the present invention have found a kind of SAPO-5/SAPO-18/SAPO-34 symbiosis composite molecular screen and preparation method thereof, this composite molecular screen catalytic performance in the reaction of organic oxygen-containing compound producing light olefins is excellent, and richly can produce propylene and butylene, particularly relative to existing congeneric elements sieve and catalyzer, butylene selectivity increases greatly, and butylene selectivity can reach 30%, and the overall selectivity of propylene and butylene can reach 70%.This novel three-phase composite molecular sieve can be used in the large-scale commercial production of propylene and butylene.

The term that this specification sheets is used and form of presentation are only used as descriptive and nonrestrictive term and form of presentation, are not intended to by any equivalents thereof exclude of the feature that represents and describe or its integral part outside when using these terms and form of presentation.

Although show and described several embodiment of the present invention, the present invention has not been restricted to described embodiment.On the contrary; those skilled in the art should recognize can carry out any accommodation and improvement to these embodiments when not departing from principle of the present invention and spirit, and protection scope of the present invention determined by appended claim and equivalent thereof.

Claims

1. a composite molecular screen, is formed by SAPO-5 molecular sieve, SAPO-18 molecular sieve and the symbiosis of SAPO-34 molecular sieve, it is characterized in that: prepare this composite molecular screen raw material used and meet following ratio:

R:SiO ₂: Al ₂o ₃: P ₂o ₅: H ₂o mol ratio is (1.2-1.8): (0.2-0.8): 1:(0.9-1.25): (40-80), wherein, R represents triethylamine or N, N-diisopropyl ethyl amine template.

2. composite molecular screen according to claim 1, wherein, prepare this composite molecular screen raw material used and meet following ratio:

R:SiO ₂: Al ₂o ₃: P ₂o ₅: H ₂o mol ratio is 1.5:(0.3,0.4 or 0.6): 1:1:50.

3. composite molecular screen according to claim 1 and 2, wherein, SiO ₂come from tetraethoxy, silicon sol, water glass, white carbon black or their arbitrary mixtures; Al ₂o ₃come from pseudo-boehmite, pseudobochmite, Alumina gel, aluminum isopropylate, aluminate, activated alumina or their arbitrary mixtures; P ₂o ₅come from phosphoric acid, phosphorous acid, phosphoric acid salt and/or phosphorous oxides.

4. composite molecular screen according to claim 1 and 2, wherein, by regulating triethylamine or N, N-diisopropyl ethyl amine template and SiO ₂consumption, adjustment SAPO-5 molecular sieve, SAPO-18 molecular sieve and the relative content of SAPO-34 molecular sieve in composite molecular screen, and then the pore passage structure distribution and the acidity that adjust described composite molecular screen.

5., according to a preparation method for one of any described composite molecular screen of claim 1-4, it comprises the following steps successively:

(1) in proportion by aluminium source, phosphorus source, silicon source, triethylamine or N, N-diisopropyl ethyl amine template and water mix at the temperature of 20 DEG C-90 DEG C, control the rate of addition of each step raw material, obtain comprising the mixing solutions of aluminium source, phosphorus source, silicon source, triethylamine or N, N-diisopropyl ethyl amine template and water;

(2) described mixing solutions is stirred until each component disperses of mixing solutions is even, mixing solutions described in ageing subsequently, until form gel mixture;

(3) gel mixture is put into 170 DEG C of-210 DEG C of reactors and carry out Hydrothermal Synthesis crystallization 24-80 hour;

(4) the solid crystal thing that crystallization is formed is separated, drier described solid crystal thing, obtain the former powder of composite molecular screen;

(5) the former powder 2-8 hour of the above-mentioned composite molecular screen of roasting at 450-650 DEG C, remove triethylamine wherein or N, N-diisopropyl ethyl amine template, obtains by the composite molecular screen of SAPO-5 molecular sieve, SAPO-18 molecular sieve and the symbiosis of SAPO-34 molecular sieve.

6. preparation method according to claim 5, wherein, described silicon source is tetraethoxy, silicon sol, water glass, white carbon black or their arbitrary mixtures; Described aluminium source is pseudo-boehmite, pseudobochmite, Alumina gel, aluminum isopropylate, aluminate, activated alumina or their arbitrary mixtures; Described phosphorus source is phosphoric acid, phosphorous acid, phosphoric acid salt and/or phosphorous oxides.

7. preparation method according to claim 5, wherein, in step (4), the solid crystal thing that described separation crystallization is formed refers to: the solid crystal thing that centrifuging is formed, to remove the crystallisate mother liquor that Hydrothermal Synthesis crystallization produces, with solid crystal thing described in deionized water wash at least one times, then solid crystal thing described in centrifuging is at least one times.

8. preparation method according to claim 5, wherein, the described mixing solutions in step (1) is prepared by the following method:

(1) respectively aluminium source, phosphorus source and silicon source are mixed with water, form aluminium source solution, phosphorus source solution and silicon source solution;

(2) lentamente aluminium source solution is added drop-wise in the solution of phosphorus source, or phosphorus source solution is added drop-wise in the solution of aluminium source, form the mixing solutions in aluminium source and phosphorus source;

(3) lentamente silicon source solution is added drop-wise in the mixing solutions in aluminium source and phosphorus source, or the mixing solutions in aluminium source and phosphorus source is added drop-wise in the solution of silicon source, form the mixing solutions in aluminium source, phosphorus source and silicon source;

(4) in the mixing solutions in described aluminium source, phosphorus source and silicon source, triethylamine or N is added again, N-diisopropyl ethyl amine template, thus form the mixing solutions comprising aluminium source, phosphorus source, silicon source, triethylamine or N, N-diisopropyl ethyl amine template and water.

9., by a catalyzer for organic oxygen-containing compound producing light olefins, the catalytic active component of described catalyzer is one of any described composite molecular screen of claim 1-4.

10. catalyzer according to claim 9, wherein, described organic oxygen-containing compound is methyl alcohol and/or dme; Described low-carbon alkene is ethene, propylene and/or butylene.