CN115869997A

CN115869997A - Silicoaluminophosphate fluidized bed catalyst and preparation method and application thereof

Info

Publication number: CN115869997A
Application number: CN202111129672.9A
Authority: CN
Inventors: 管洪波; 刘红星; 叶迎春; 丁佳佳
Original assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Current assignee: China Petroleum and Chemical Corp; Sinopec Shanghai Research Institute of Petrochemical Technology
Priority date: 2021-09-26
Filing date: 2021-09-26
Publication date: 2023-03-31

Abstract

The invention discloses a silicoaluminophosphate fluidized bed catalyst and a preparation method and application thereof. The preparation method of the silicoaluminophosphate fluidized bed catalyst comprises the following steps: (1) Mixing a second silicon source, a second aluminum source, a second phosphorus source and water to obtain a mixed solution I, mixing the mixed solution I with the seed crystal, and preparing into dry glue; mixing the dry glue with a binder, a base material and water to form a suspension III; (2) Shearing the suspension III obtained in the step (1) at a high speed, and then performing spray drying to obtain solid microspheres; (3) And (3) carrying out gas phase crystallization on the solid microspheres obtained in the step (2), an organic template agent and water, and roasting to obtain the silicoaluminophosphate fluidized bed catalyst. The silicoaluminophosphate fluidized bed catalyst prepared by the method has the characteristics of good wear resistance and high crystallinity, and is high in catalytic activity and selectivity of products ethylene and propylene when used for preparing ethylene and propylene from methanol and/or dimethyl ether.

Description

Silicoaluminophosphate fluidized bed catalyst and preparation method and application thereof

Technical Field

The invention relates to the field of preparation of molecular sieve catalysts, in particular to a silicoaluminophosphate fluidized bed catalyst, a preparation method thereof and application thereof in preparation of olefin from an oxygen-containing compound.

Background

Ethylene and propylene are important basic raw materials for modern petrochemical industry. The traditional preparation method of ethylene and propylene depends on petroleum raw materials, and combines the actual distribution situation of fossil energy of rich coal, poor gas and little oil in China, so that the production level of the coal chemical industry in China is improved and changed, and the development of a novel coal chemical technology accords with the national security and energy strategy in China. The methanol-to-olefin (MTO) route has attracted extensive attention because the raw material can be obtained from synthesis gas in a large amount, cheaply and conveniently, and in recent years, dozens of methanol-to-olefin (MTO) devices are put into commercial operation one after another, so that very good economic and social benefits are obtained.

The core of the technology for preparing olefin from methanol is the development of molecular sieve catalysts, and most of the catalysts used in the early preparation of olefin from methanol are silicon-aluminum zeolite molecular sieves, such as ZSM-5, but the pore size is relatively large, the acidity is too strong, and the yield of low-carbon olefin is not high. In 1982, united states carbon compound company (UCC) synthesized SAPO series silicoaluminophosphate molecular sieves for the first time, among which SAPO-34 molecular sieves, which have a chabazite-like structure, a small pore diameter, moderate acidity and strong hydrothermal stability, and showed excellent low carbon olefin selectivity in the reaction of catalyzing methanol to prepare low carbon olefins, have attracted extensive attention of researchers in various countries.

When the molecular sieve is applied to industrial catalysis, 100 percent of the molecular sieve can not be adopted to prepare a catalyst for industrial process. Firstly, because the molecular sieve has poor cohesive property and too fine granularity, the molecular sieve is difficult to be formed into a catalyst which is directly applied to an industrial process, and secondly, because the manufacturing cost of the molecular sieve is generally higher, if 100 percent of the molecular sieve is adopted as the industrial catalyst, the cost is increased. Industrial processes generally require that the catalyst be of a shape and strength to accommodate an industrial reactor. In the case of fluidized bed reactors, the catalyst itself is required to have good attrition resistance to meet the requirements of industrial processes due to the continuous circulating flow or turbulence of the catalyst in the reactor. In the prior art, the molecular sieve is prepared into a fluidized bed catalyst, and generally, the molecular sieve is directly prepared into suspension with a binder, a liquid medium and the like, and then the suspension is subjected to shearing, drying, roasting and other means to prepare a finished microsphere catalyst. For example, CN101259425A, CN1341584A is the molecular sieve fluidized bed catalyst prepared by the method. However, the activity and selectivity of the fluidized bed molecular sieve catalyst prepared by the above method still need to be further improved. CN101318143B aims at the problems of low wear resistance and poor catalytic performance of a fluidized bed catalyst for preparing ethylene and propylene from methanol and/or dimethyl ether, a method for modifying a binder is adopted, so that the high wear resistance of the fluidized bed catalyst is improved, but the method still has the problem that acidic slurry causes damage to a molecular sieve structure to a certain extent in the preparation process of a microsphere catalyst.

Disclosure of Invention

Aiming at the defects of the prior art, the invention provides a silicoaluminophosphate fluidized bed catalyst and a preparation method and application thereof. The silicoaluminophosphate fluidized bed catalyst prepared by the method has the characteristics of good wear resistance and high crystallinity, and is high in catalytic activity and selectivity of products ethylene and propylene when used for preparing ethylene and propylene from methanol and/or dimethyl ether.

The invention provides a preparation method of a silicoaluminophosphate fluidized bed catalyst, which comprises the following steps:

(1) Mixing a second silicon source, a second aluminum source, a second phosphorus source and water to obtain a mixed solution I, mixing the mixed solution I with the seed crystal, and preparing into dry glue; mixing the dry glue with a binder, a base material and water to form a suspension III;

(2) Shearing the suspension III obtained in the step (1) at a high speed, and then performing spray drying to obtain solid microspheres;

(3) And (3) carrying out gas phase crystallization on the solid microspheres obtained in the step (2), an organic template agent and water, and roasting to obtain the silicoaluminophosphate fluidized bed catalyst.

Further, the synthesis method of the seed crystal in the step (1) comprises the following steps: preparing an initial gel mixture from a first phosphorus source, a first aluminum source, a first silicon source, a template agent and water, stirring and aging for 1-24 h, performing hydrothermal crystallization for 0.1-8 h at 170-220 ℃, and then performing solid-liquid separation to obtain the seed crystal.

Further, in the method for synthesizing the seed crystal in the step (1), in the initial gel mixture, the first silicon source is SiO ₂ The first aluminum source is calculated by Al ₂ O ₃ Counting the first phosphorus source as P ₂ O ₅ Counting, template agent: siO 2 ₂ ：Al ₂ O ₃ ：P ₂ O ₅ ：H ₂ The molar ratio of O is (0.5-10): (0.05 to 3): (0.2-3): (0.2-3): (20-200).

Further, in the method for synthesizing the seed crystal in the step (1), the hydrothermal crystallization temperature is 190-210 ℃, and the hydrothermal crystallization time is 0.5-6 hours.

Further, in the step (1), a second phosphorus source, a second aluminum source, a second silicon source and water are mixed to obtain a mixed solution I, wherein the second silicon source is SiO ₂ The second aluminum source is calculated as Al ₂ O ₃ In terms of a second phosphorus source, P ₂ O ₅ The molar ratio of each substance is as follows: al (aluminum) ₂ O ₃ :SiO ₂ :P ₂ O ₅ :H ₂ O＝1:(0.05～2):(0.05～2):(10～200)。

Further, mixing the mixed solution I and the seed crystal in the step (1) to form a mixed solution II, wherein the seed crystal accounts for 1-30% of the weight of the dry basis in the mixed solution II, heating to 80-120 ℃ under stirring, and evaporating water to obtain the dry glue.

Further, after the dry glue is ground in the step (1), the dry glue is uniformly mixed with the binder, the matrix material and water to form a suspension III.

Further, in the step (1), the pH value of the suspension III is 2.5-5.5; the solid content in the suspension III is 20wt% -50 wt%. Further, in the step (1), the first aluminum source or the second aluminum source is at least one selected from aluminum isopropoxide, pseudo-boehmite or alumina; the first phosphorus source or the second phosphorus source is at least one selected from phosphoric acid, phosphate or phosphorous acid; the first silicon source or the second silicon source is at least one of TEOS, white carbon black or silica sol.

Further, in the seed crystal synthesis method in the step (1), the template is at least one selected from TEAOH, TPA, triethylamine, diethylamine or morpholine.

Further, the binder in the step (1) is selected from silica sol and/or aluminum sol; the matrix material is at least one of clay, hydrotalcite and kaolin.

Further, in the step of mixing the dry glue with the binder, the matrix material and the water to form the suspension III in the step (1), the weight ratio of the dry glue to the binder, the matrix material and the water is (10-30): (5-10): (5-20): (40-80).

Further, in step (2), the high speed shearing is required to make at least 90% of the particles in the suspension have an average particle size of less than 8 microns, and preferably an average particle size of 2 to 5 microns.

Further, in the step (2), the average particle size of the solid microspheres is 50 to 90 micrometers, and preferably the average particle size is 60 to 80 micrometers.

Further, in the step (2), the spray drying can adopt a conventional method in the field, wherein the inlet temperature is 270-300 ℃, the outlet temperature is 110-130 ℃, and the rotating speed of the rotary atomizer is 8000-16000 rpm.

Further, in the step (3), the organic template agent is triethylamine and morpholine, wherein the mass ratio of triethylamine to morpholine is 1.5-4: 1.

further, in the step (3), the crystallization temperature is 140 to 220 ℃, the crystallization time is 12 to 72 hours, and preferably, the crystallization temperature is 160 to 200 ℃, and the crystallization time is 24 to 48 hours.

Further, the mass ratio of the solid microspheres, the organic template and the water in the step (3) is (20-30): (20 to 40): (30 to 60).

Further, the gas phase crystallization in the step (3) is more specifically: placing the solid microspheres on the upper part of a gas phase reaction kettle, placing a mixture consisting of an organic template agent and water on the liquid phase position at the lower part of the reaction kettle, reacting for 12-72 hours at the crystallization temperature of 140-220 ℃, and roasting for 3-6 hours at the temperature of 400-700 ℃ to obtain the silicoaluminophosphate fluidized bed catalyst.

In a second aspect, the invention provides a silicoaluminophosphate fluidized bed catalyst prepared by the above method.

Further, the catalyst comprises a silicoaluminophosphate molecular sieve, preferably at least one of SAPO-5, SAPO-11, SAPO-17, SAPO-18, SAPO-34, SAPO-35, SAPO-44, SAPO-47 and SAPO-56.

Furthermore, the molecular sieve accounts for 5-80 wt% of the catalyst.

Furthermore, the catalyst also comprises a binder and a matrix material.

Further, the relative crystallinity of the silicoaluminophosphate molecular sieve in the catalyst is 100-130%.

Further, the silicoaluminophosphate fluidized bed catalyst has an attrition index of not greater than 1.0 mass%/hour.

In a third aspect, the invention provides the use of the silicoaluminophosphate fluidized bed catalyst in the preparation of olefins from oxygenates.

Further, the oxygenate is preferably methanol and/or dimethyl ether, and the olefin is propylene and ethylene.

Further, the reaction conditions for the preparation of olefins from oxygenates include: the reaction temperature is 440-490 ℃, and the mass space velocity is 4.0-15.0 h ^-1 The reaction pressure is 0.10-0.17 MPa.

Further, the application employs a fluidized bed.

Compared with the prior art, the invention has the following advantages:

(1) The inventor finds that in the spray drying pulping process of the silicoaluminophosphate fluidized bed catalyst prepared by the preparation method in the prior art, the acidic solution environment can erode the framework structure of the silicoaluminophosphate molecular sieve, so that the wear resistance of the finished catalyst is influenced, the original B acid position of the molecular sieve can be damaged to a certain extent, the loss of the B acid position is caused, and the performance of the catalyst is further influenced. In the method provided by the invention, the abrasion resistance and the catalytic performance of the catalyst are prevented from being reduced due to the damage of the molecular sieve framework by a method of molding and then crystallizing. In the process of preparing the dry glue, the new large crystal molecular sieve rich in lattice defects is introduced as a seed crystal, and in the process of preparing the dry glue by evaporating the solution to dryness, the large crystal molecular sieve collapses into tiny crystal fragments in a hydrothermal environment and is dispersed in the dry glue, so that the molecular sieve with high crystallinity can be more easily obtained in the gas phase crystallization process. The solid microspheres obtained by spray drying the dry glue are not contacted with a high-temperature aqueous solution in the gas phase crystallization process, so that the prepared silicoaluminophosphate fluidized bed catalyst has the characteristics of high molecular sieve crystallinity and good wear resistance.

(2) The silicoaluminophosphate fluidized bed catalyst prepared by the preparation method of the invention has higher main product selectivity and longer catalyst life in the reaction of preparing olefin from methanol and/or dimethyl ether.

Drawings

FIG. 1 is an XRD pattern of the fluidized bed microspherical catalyst obtained in examples 2 to 6 and comparative examples 1 to 2.

Detailed Description

The following detailed description of the embodiments of the present invention is provided, but it should be noted that the scope of the present invention is not limited by the embodiments, but is defined by the appended claims.

All publications, patent applications, patents, and other references mentioned in this specification are herein incorporated by reference in their entirety. Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art. In case of conflict, the present specification, including definitions, will control.

When the specification concludes with the claims defining the existence of materials, methods, procedures, means, or components, or the like, that are regarded as being "known to one of ordinary skill in the art", "prior art", or the like, it is intended that the subject matter so derived encompass those materials, methods, procedures, means, or components which have been conventionally used in the art at the time of filing this application, but which may not be so commonly used at the present time, but will become known in the art as being suitable for a similar purpose.

It should be expressly understood that two or more of the aspects (or embodiments) disclosed in the context of this specification can be combined with each other as desired, and that such combined aspects (e.g., methods or systems) are incorporated in and constitute a part of this original disclosure, while remaining within the scope of the present invention.

Unless otherwise expressly indicated, all percentages, parts, ratios, etc. mentioned in this specification are by weight unless otherwise not in accordance with the conventional knowledge of those skilled in the art.

In the present invention, the crystalline phase of the molecular sieve is performed on a Bruker D8 polycrystalline X-ray diffraction (XRD) instrument, a graphite monochromator, using a Cu-Ka radiation source (Ka 1 wavelength λ =0.15406 nm), a scanning angle 2 θ of 5 to 50 °, and a scanning rate of 1 °/min.

In the invention, when the sample is subjected to XRD measurement under the same test conditions, the better the crystallinity of the sample is, the stronger the corresponding XRD characteristic diffraction peak is, and the relative crystallinity of other samples is calculated by taking the sample in the comparative example 1 as the crystallinity of 100%.

In the invention, the abrasion index measuring method comprises the following steps: weighing 50.0g of microspherical catalyst on a VINCI Technologies D5757-11 abrader, loading the microspherical catalyst into the abrader, controlling and adjusting the air feeding pressure (pressure after adjustment) to be 2.0bar (gauge pressure), enabling the working flow to be about 10L/min (under a standard state), starting timing at the same time, blowing and grinding for 1h, stopping gas supply, taking off a powder collecting system, weighing the mass of the powder collecting system to be accurate to 0.01g, then reinstalling the powder collecting system on the abrader, continuing blowing and grinding for 4h, stopping gas supply, taking off the powder collecting system, weighing the mass of the powder collecting system to be accurate to 0.01g. The abrasion index w, the value of which is expressed in mass fraction per hour (%/h), is calculated according to the formula (1):

in the formula: m is ₅ -the mass of the powder collection system after 5h in grams (g);

m ₁ -a mass value in grams (g) for the powder collection system after 1 h;

m is a number of masses of the sample in grams (g);

m ₀ -the mass of the powder collection system before testing in grams (g).

[ example 1 ] A method for producing a polycarbonate

12.1 g of gamma-Al ₂ O ₃ Mixing with 35.0 g of deionized water uniformly to form a mixed solution a;23.3 grams of orthophosphoric acid (85% by weight), 37.5 grams of deionized water were mixed well to form solution b; a and b are mixed and stirred for 2 hours at room temperature to form a mixed solution c; keeping stirring, sequentially adding 31 g of triethylamine, 4.5 g of silica sol and 27.0 g of deionized water into the solution c, and fully stirring to obtain an initial gel mixture for synthesizing the SAPO-34 molecular sieve; wherein the silicon source is SiO ₂ Calculated by Al as the aluminum source ₂ O ₃ In terms of phosphorus source, P ₂ O ₅ Counting, template agent: siO 2 ₂ ：Al ₂ O ₃ ：P ₂ O ₅ ：H ₂ The molar ratio of O is 3:0.3:1:1:55. crystallizing the mixture at 200 deg.C for 4 hr, quenching, and performing solid-liquid separation to obtain seed crystal.

[ example 2 ]

23g 85% phosphoric acid and 28.2gSiO were mixed under stirring ₂ Adding 30% silica sol into 94g deionized water, mixing thoroughly, adding 14.6g alumina, and adding Al ₂ O ₃ ∶P ₂ O ₅ ∶1.25SiO ₂ ∶75H ₂ O, stirring for 24 hours at room temperature, adding 3.0g of the seed crystal obtained in example 1, gradually raising the temperature to 80 ℃, and continuing to stir for 3-5When the reaction time is short, the viscosity of the system gradually increases and becomes colloidal as water evaporates during the reaction. Putting the colloid into an oven, heating at 120 ℃ for more than 12 hours, and completely evaporating the water to obtain the dry colloid.

Grinding the dry glue into powder, and weighing the raw materials according to the proportion of 20 percent (mass) of dry glue powder, 13 percent (mass) of kaolin, 7 percent (mass) of alumina sol and 60 percent (mass) of deionized water. Except for water, the raw material proportion is dry basis mass ratio. The following operations are carried out: firstly, mixing weighed dry glue powder with deionized water, stirring for 1 hour, and fully stirring; shearing for 15 minutes at high speed by using a high-speed shearing machine, adding the alumina sol, quickly stirring for 15 minutes, and shearing for 15 minutes by using the high-speed shearing machine; adding kaolin, stirring for 30 minutes to obtain a uniform state, and obtaining a suspension. The resulting suspension was subjected to high-speed shearing with a high-speed shearing machine for 45 minutes to obtain a suspension before spray-drying, which had a pH of 4.5. The particle size of this suspension was measured by a laser particle sizer and the average particle size was 3.6 microns. The suspension was spray dried at an inlet temperature of 290 deg.C, an outlet temperature of 130 deg.C, and a rotary atomizer speed of 15000 rpm. Solid microspheres with an average particle size of 80 microns were obtained.

9.0g of solid microspheres are placed at the upper part of a reaction kettle, and the lower part of the reaction kettle is a mixed solution consisting of 7.5g of composite template agent and 15g of water, wherein the mass ratio of triethylamine to morpholine is 3: 1. And (3) crystallizing the reaction kettle for 48 hours at 180 ℃ after sealing, fully washing and filtering the obtained product after cooling, drying the product for 5 hours at 120 ℃, and roasting the product for 6 hours at 550 ℃ to obtain the silicoaluminophosphate fluidized bed catalyst. The molecular sieve in the catalyst accounts for about 40-50 wt%.

[ example 3 ]

The procedure and conditions of example 2 were followed except that 5g of seed crystals were added during the preparation of the dry gel. The molecular sieve in the catalyst accounts for about 40-50 wt%.

[ example 4 ]

The procedure and conditions of example 2 were followed except that the amount of seed crystals added during the preparation of the dry gel was 8g. The molecular sieve in the catalyst accounts for about 40-50 wt%.

[ example 5 ]

The procedure and conditions of example 3 were followed except that the spray slurry was weighed in proportions of 15% by mass of dry colloidal powder, 18% by mass of kaolin, 7% by mass of alumina sol, and 60% by mass of deionized water. The molecular sieve in the catalyst accounts for about 40-50 wt%.

[ example 6 ]

The procedure and conditions of example 3 were followed except that the spray slurry was prepared by weighing 25 mass% of dry glue powder, 8 mass% of kaolin, 7 mass% of alumina sol and 60 mass% of deionized water. The molecular sieve in the catalyst accounts for about 40-50 wt%.

[ example 7 ]

The procedures and conditions of example 3 were followed except that 9.0g of solid microspheres were placed in the upper part of a reaction vessel, and the lower part of the reaction vessel was a mixed solution of 10.0g of composite template agent and 15g of water, wherein the mass ratio of triethylamine to TEAOH was 3: 1. After the reaction kettle is sealed, the mixture is crystallized for 36 hours at 200 ℃. The molecular sieve in the catalyst accounts for about 40-50 wt%.

Comparative example 1

12.1 g of gamma-Al ₂ O ₃ Evenly mixing the mixture and 35.0 g of deionized water to form a mixed solution a;23.3 grams of orthophosphoric acid (85% by weight), 37.5 grams of deionized water were mixed well to form solution b; a and b are mixed and stirred for 2 hours at room temperature to form a mixed solution c; keeping stirring, sequentially adding 31 g of triethylamine, 4.5 g of silica sol and 27.0 g of deionized water into the solution c, and fully stirring to obtain an initial gel mixture for synthesizing the SAPO-34 molecular sieve; crystallizing the mixture at 200 deg.C for 24 hr, separating solid from liquid, washing, and drying to obtain molecular sieve raw powder.

The raw materials are weighed according to the proportion of 20 percent (mass) of molecular sieve raw powder, 13 percent (mass) of kaolin, 7 percent (mass) of alumina sol and 60 percent (mass) of deionized water. Except for water, the raw material proportion is dry basis mass ratio. The following operations are carried out: firstly, mixing a weighed molecular sieve with deionized water, stirring for 1 hour, and fully stirring; shearing for 15 minutes at high speed by using a high-speed shearing machine, adding the alumina sol, quickly stirring for 15 minutes, and shearing for 15 minutes by using the high-speed shearing machine; kaolin was added and stirred for 30 minutes to obtain a homogeneous state and a suspension with a pH of 4.4. The resulting suspension was subjected to high-speed shearing using a high-speed shearing machine for 45 minutes to obtain a suspension before spray-drying. The particle size of this suspension was measured by a laser particle sizer and the average particle size was 4.2 microns. Spray-drying the suspension at an inlet temperature of 280 ℃, an outlet temperature of 110 ℃ and a rotational speed of 10000rpm for a rotary atomizer. Obtaining the fluidized bed catalyst microspheres. The molecular sieve in the catalyst accounts for about 40-50 wt%.

Comparative example 2

The procedures and conditions of example 2 were followed except that no seed crystal was added during the dry gel preparation. The molecular sieve in the catalyst accounts for about 40-50 wt%.

[ example 8 ]

XRD (X-ray diffraction) characterization is carried out on the fluidized bed microspherical catalysts obtained in examples 2-6 and comparative examples 1-2, the result is shown in figure 1, the molecular sieve in the obtained fluidized bed catalyst is SAPO-34, and compared with comparative example 1, the SAPO-34 molecular sieve in the obtained catalysts has better crystallinity. The relative crystallinity of examples 2 to 6 is shown in Table 1, assuming that the crystallinity of comparative example 1 is 100%.

TABLE 1 relative crystallinity of examples and comparative examples

Sample(s)

Comparative example 1

Comparative example 2

Example 2

Example 3

Example 4

Example 5

Example 6

Relative degree of crystallinity

100％

105％

108％

112％

119％

110％

127％

[ example 9 ]

The fluidized bed microspherical catalysts obtained in examples 2 to 7 and comparative examples 1 to 2 were evaluated in a fluidized bed under the following reaction conditions: 40g of catalyst, pure methanol feeding, reaction temperature of 480 ℃, space velocity (WHSV) of 4.0h ^-1 And the pressure is 0.1MPa. The results are shown in Table 2.

TABLE 2 catalytic performance of methanol to olefins of examples and comparative examples

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[ example 10 ]

The attrition index of the fluidized bed microspherical catalyst obtained in examples 2 to 7 and comparative examples 1 to 2 was measured. The results are shown in Table 2.

TABLE 2 abrasion index of catalysts obtained in examples and comparative examples

Sample(s)	Abrasion index (% by mass/hour)
		Example 2	0.52
Example 3	0.51
		Example 4	0.61
Example 5	0.44
		Example 6	0.70
Example 7	0.74
		Comparative example 1	1.22
Comparative example 2	1.01

Claims

1. A method for preparing a silicoaluminophosphate fluidized bed catalyst, comprising:

2. The method according to claim 1, wherein in step (1), the second phosphorus source, the second aluminum source, the second silicon source and water are mixed to obtain a mixture I, and the silicon source is SiO ₂ Calculated by Al as the aluminum source ₂ O ₃ In terms of phosphorus source, P ₂ O ₅ The molar ratio of each substance is as follows: al (aluminum) ₂ O ₃ :SiO ₂ :P ₂ O ₅ :H ₂ O＝1:(0.05～2):(0.05～2):(10～200)。

3. The preparation method according to claim 1, wherein the mixture I and the seed crystal in the step (1) are mixed into a mixture II, the seed crystal accounts for 1-30% of the dry weight of the mixture II, the mixture is stirred, the temperature is raised to 80-120 ℃, and water is evaporated to obtain the dry glue.

4. The method according to claim 1, wherein in the step (1), the first aluminum source or the second aluminum source is at least one selected from aluminum isopropoxide, pseudo-boehmite, and alumina; the first phosphorus source or the second phosphorus source is at least one selected from phosphoric acid, phosphate or phosphorous acid; the first silicon source or the second silicon source is at least one of TEOS, silica white or silica sol.

5. The method according to claim 1, wherein in the step (2), the average particle diameter of the solid microspheres is 50 to 90 micrometers, preferably 60 to 80 micrometers.

6. The method of claim 1, wherein in the step (3), the crystallization temperature is 140-220 ℃ and the crystallization time is 12-72 hours, preferably 160-200 ℃ and the crystallization time is 24-48 hours.

7. The preparation method according to claim 1, wherein the organic template in the step (3) is triethylamine and morpholine, wherein the mass ratio of triethylamine to morpholine is 1.5-4: 1; the mass ratio of the solid microspheres to the organic template to water is (20-30): (20 to 40): (30-60).

8. A silicoaluminophosphate fluidized bed catalyst obtainable by the method of manufacture according to any one of claims 1 to 7.

9. The silicoaluminophosphate fluidized bed catalyst of claim 8, wherein the catalyst comprises a silicoaluminophosphate molecular sieve, preferably at least one of SAPO-5, SAPO-11, SAPO-17, SAPO-18, SAPO-34, SAPO-35, SAPO-44, SAPO-47, SAPO-56.

10. The silicoaluminophosphate fluidized bed catalyst of claim 8, wherein the attrition index of the catalyst is not greater than 1.0 mass%/hour.

11. Use of the silicoaluminophosphate fluidized bed catalyst according to any one of claims 8 to 10 for the production of olefins from oxygenates.

12. Use according to claim 11, wherein the oxygenate is methanol and/or dimethyl ether.

13. The use according to claim 11, wherein the reaction conditions for the oxygenate to olefins comprise: the reaction temperature is 440-490 ℃, and the mass space velocity is 4.0-15.0 h ^-1 The reaction pressure is 0.10-0.17 MPa.