Preparation method and application of SAPO or AlPO molecular sieve

Abstract

The invention relates to a preparation method of a novel SAPO or AlPO molecular sieve, which comprises the following steps: (1) carrying out molding treatment on a first mixture containing a first template agent, an aluminum source, a phosphorus source and an optional silicon source to obtain a precursor; and (2) carrying out crystallization reaction on a second mixture containing the precursor and a second template agent to obtain the SAPO or AlPO molecular sieve. According to the preparation method, the SAPO or AlPO molecular sieve is obtained in a manner of directly mixing, molding and crystallizing the raw materials, so that the preparation method has the characteristics of high yield and single-kettle yield, energy conservation and emission reduction, and can meet the industrial production of high-performance adsorbents.

Description

Technical Field

[0001] The invention belongs to the field of molecular sieve synthesis, and in particular relates to a preparation method of SAPO or AlPO molecular sieve and application thereof. Background Art

[0002] In the 19th century, Union Carbide Corporation of the United States successfully synthesized aluminum phosphate molecular sieves and their derivatives. Aluminum phosphate / silicoaluminum phosphate molecular sieves have good thermal stability and hydrothermal stability, adjustable acidity, etc. They can be used for catalytic reactions of various hydrocarbons and show good adsorption properties. They have good application prospects in the fields of petrochemicals, coal chemical industry, functional materials, etc. 4 The hydrothermal crystallization method is commonly used in the synthesis of molecular sieves. During the crystallization and washing process, a large amount of wastewater containing organic amines / quaternary ammonium bases will be generated, which is very difficult to treat. SAPO and AlPO 4 The preparation process of molecular sieves generally involves first crystallizing to obtain molecular sieve powder, then mixing it with a binder, a carrier, etc., and obtaining a formed molecular sieve through spraying, extrusion, etc. This method has a long preparation process, high cost, and low product adsorption capacity.

[0003] Therefore, developing a new method for preparing spherical SAPO or AlPO molecular sieves is of great significance to the sustainable development of economy and environment. Summary of the invention

[0004] In view of the problems of long production process and high cost of SAPO or AlPO molecular sieve in the prior art, the present invention provides a new method for preparing spherical SAPO or AlPO molecular sieve. The preparation method adopts the method of directly mixing and molding raw materials and recrystallizing to obtain SAPO or AlPO molecular sieve, which has the characteristics of high yield and single-pot productivity, energy saving and emission reduction, and can meet the industrial production of high-performance adsorbents.

[0005] In order to achieve the above object, one aspect of the present invention provides a method for preparing SAPO or AlPO molecular sieve, the preparation method comprising:

[0006] (1) subjecting a first mixture containing a first template, an aluminum source, a phosphorus source, and an optional silicon source to a molding process to obtain a precursor;

[0007] (2) subjecting the second mixture containing the precursor and the second template to a crystallization reaction to obtain the SAPO or AlPO molecular sieve.

[0008] In some embodiments, in step (1), the silicon source is SiO 2 The aluminum source is Al 2 O 3 Phosphorus source is P 2 O 5The molar ratio of the silicon source, the aluminum source and the phosphorus source is (0-1.0):1.0:(0.8-1.2), preferably (0-0.6):1.0:(0.8-1.0). In some specific embodiments, the silicon source is SiO 2 The aluminum source is Al 2 O 3 Phosphorus source is P 2 O 5 The molar ratio of the silicon source, the aluminum source and the phosphorus source can be 0.6:1:0.8, 0.0:1:1, 0.3:1:1, 0.5:1:1, 0.4:1:0.9 or any value therebetween.

[0009] In some embodiments, the first mixture includes a first template, an aluminum source, a phosphorus source, and a silicon source, and a silicoaluminophosphate (SAPO) molecular sieve is obtained according to the preparation method. In other embodiments, the first mixture includes a first template, an aluminum source, and a phosphorus source, and an aluminum phosphate (AlPO) molecular sieve is obtained according to the preparation method.

[0010] In some embodiments, the phosphorus source includes at least one of phosphoric acid, phosphorous acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate or polyphosphoric acid, preferably selected from phosphoric acid and / or ammonium hydrogen phosphate.

[0011] In some embodiments, the aluminum source includes at least one of pseudo-boehmite, aluminum hydroxide, aluminum isopropoxide, or aluminum oxide, preferably selected from pseudo-boehmite and / or aluminum isopropoxide.

[0012] In some embodiments, the silicon source includes at least one of white carbon black, silica sol or silica gel, preferably selected from white carbon black.

[0013] In some embodiments, the first template comprises at least one of triethylamine, diethylamine, di-n-propylamine, cyclohexylamine, morpholine, or a quaternary ammonium base.

[0014] In some embodiments, the second template includes at least one of triethylamine, diethylamine, di-n-propylamine, cyclohexylamine, morpholine, or a quaternary ammonium base.

[0015] In some embodiments, the first templating agent is the same as the second templating agent.

[0016] In the present invention, a first template is added during the molding process, and the first template reacts with the raw material to form the primary structure of the molecular sieve, inducing crystallization. If the template is only added during the crystallization reaction, the liquid-solid ratio will be too high, affecting the strength and product structure of the prepared molecular sieve.

[0017] In some embodiments, the aluminum source is Al 2 O 3The ratio of the molar amount of the aluminum source to the sum of the molar amounts of the first template and the second template is 1:(0.7-2.0), preferably 1:(0.8-1.5). 2 O 3 The ratio of the molar amount of the aluminum source to the sum of the molar amounts of the first template and the second template can be 1:0.7, 1:1.2, 1:1.25, 1:1.5, 1:2.0 or any value therebetween.

[0018] In some embodiments, the molar ratio of the first template to the second template is (0.6-0.95): (0.05-0.4), preferably (0.7-0.95): (0.05-0.3), and more preferably (0.85-0.95): (0.05-0.15). In some embodiments, the molar ratio of the first template to the second template is 0.6: 0.4, 0.7: 0.3, 0.8: 0.2, 0.85: 0.15, 0.9: 0.1, 0.95: 0.05 or any value therebetween.

[0019] In some embodiments, the water content of the precursor is 2-40%, preferably 5-30%, more preferably 10-20%. In some embodiments, the water content of the precursor is 2%, 10%, 15%, 20%, 40% or any value therebetween.

[0020] In some embodiments, the forming process comprises at least one of spray drying, spheronization, or extrusion pelletization and spheronization.

[0021] In some embodiments, the temperature of the crystallization reaction is 160-200°C, preferably 165-195°C.

[0022] In some embodiments, the crystallization reaction time is 12 to 48 hours, preferably 24 to 36 hours.

[0023] In some embodiments, step (1) further comprises drying the product after the molding process to obtain the precursor.

[0024] In some embodiments, the drying temperature is 80-150°C, preferably 90-120°C.

[0025] In some embodiments, the drying time is 2 to 24 hours, preferably 8 to 20 hours.

[0026] In some embodiments, step (2) further comprises calcining the product after the crystallization reaction to obtain the SAPO or AlPO molecular sieve.

[0027] In some embodiments, the calcination temperature is 550-650°C, preferably 550-580°C.

[0028] In some embodiments, the calcination treatment time is 2 to 12 hours, preferably 4 to 6 hours.

[0029] In some embodiments, the preparation method includes the following steps: (1) adding an aluminum source, a silicon source, and a phosphorus source to a template aqueous solution to form a precursor A, (2) drying the precursor A in step (1) to obtain a precursor B, (3) adding a stoichiometric ratio of the template to the precursor B obtained in step (2) for crystallization to obtain a product C, and (4) washing, filtering, drying, and calcining the crystallized product C in step (3) to obtain a SAPO or AlPO molecular sieve.

[0030] The present invention adopts the above preparation method to directly prepare SAPO or AlPO with good adsorption performance. 4 Molecular sieves improve the single-pot yield, reduce production costs, and generate almost no waste liquid. This is a green and environmentally friendly molecular sieve production method. 4 The water absorption rate of molecular sieve is >30%, which is a high-performance adsorbent.

[0031] Another aspect of the present invention provides a SAPO or AlPO molecular sieve prepared by the preparation method described in the first aspect.

[0032] In some embodiments, the strength of the SAPO or AlPO molecular sieve is 40 to 80 N / particle, preferably 65 to 80 N / particle.

[0033] Another aspect of the present invention provides the use of the SAPO or AlPO molecular sieve prepared by the above preparation method as an adsorbent or catalyst.

[0034] In some embodiments, the SAPO or AlPO molecular sieve is used to remove water and impurities from an organic solvent.

[0035] In some embodiments, the organic solvent includes an alcohol solvent, including but not limited to isopropanol, ethanol, methanol, and the like.

[0036] Compared with the prior art, the present invention has at least the following beneficial effects:

[0037] (1) The present invention uses raw materials to directly mix, and then obtain SAPO or AlPO through molding, drying, crystallization, calcination, etc. 4The present invention directly obtains a shaped molecular sieve by a one-step method, which has the characteristics of high yield and single-pot productivity, energy saving and emission reduction, and basically no waste liquid is generated, which can meet the industrial production of high-performance adsorbents. The SAPO / AlPO prepared by the present invention 4 The static water absorption rate of the molecular sieve is greater than 30%, and it can be used to remove water and impurities from organic solvents, reducing production costs and wastewater treatment costs.

[0038] (2) The preparation method of the present invention can directly obtain a formed spherical molecular sieve, shortening the production process, reducing production costs, improving the single-pot yield, and being simple to operate. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] Figure 1 This is a process flow chart for preparing SAPO molecular sieve according to Example 1 of the present invention.

[0040] Figure 2 This is the XRD spectrum of the SAPO molecular sieve prepared in Example 1 of the present invention.

[0041] Figure 3 This is the XRD spectrum of the SAPO molecular sieve prepared in Comparative Example 1 of the present invention. DETAILED DESCRIPTION

[0042] For ease of understanding of the present invention, the present invention enumerates embodiment as follows. But those skilled in the art should understand that the embodiment is only to help understand the present invention, should not be regarded as specific limitation of the present invention. The endpoints and any value of the range disclosed in this article are not limited to the precise range or value, and these ranges or values ​​should be understood to include values ​​close to these ranges or values.

[0043] The endpoints and any values ​​of the ranges disclosed in this article are not limited to the precise ranges or values, and these ranges or values ​​should be understood to include values ​​close to these ranges or values. For numerical ranges, the endpoint values ​​of each range, the endpoint values ​​of each range and the individual point values, and the individual point values ​​can be combined with each other to obtain one or more new numerical ranges, which should be considered as specifically disclosed in this article.

[0044] The present invention will be described in detail below through examples. In the following examples, the test method for water absorption adopts the national standard "Zelectrolyte Static Water Adsorption Determination Method GB 6287-86". The molecular sieve strength test method refers to the national standard "Molecular sieve crushing resistance test method HG / T 2783-2020".

[0045] Example 1 Preparation of SAPO Molecular Sieve

[0046] refer to Figure 1The method shown is used to prepare SAPO molecular sieves.

[0047] (1) The molar ratio of silicon source, aluminum source and phosphorus source is SiO 2 :Al 2 O 3 :P 2 O 5 =0.6:1:0.8, wherein the phosphorus source is phosphoric acid, the aluminum source is aluminum isopropoxide, and the silicon source is white carbon black. The aluminum source, the silicon source, and the phosphorus source are added with a first template and water for molding, wherein the first template is triethylamine, and the molding method is spheronization molding, to obtain a spherical precursor A.

[0048] (2) Precursor A is dried to obtain spherical precursor B. The drying temperature is 120° C. and the drying time is 8 h.

[0049] (3) The obtained precursor B is added with a second template agent in a stoichiometric ratio for crystallization. The second template agent is triethylamine. The molar ratio of the first template agent to the second template agent is 0.85:0.15. The aluminum source (in the form of Al 2 O 3 The ratio of the molar amount of the first template and the molar amount of the second template is 1:1.2. The water content of the precursor B is 20%, the crystallization temperature is 195°C, and the crystallization time is 24h to obtain a molecular sieve.

[0050] (4) The crystallized molecular sieve is washed, filtered, dried and calcined at a temperature of 550°C for 4 hours. The strength of the molecular sieve prepared by this method is 80N / particle, and the static water absorption rate is 33%. Its XRD spectrum is as follows: Figure 2 shown.

[0051] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.99%, water is 100 mg / L, diisopropylamine is 30 mg / L, acetone is 70 mg / L, and other impurities are 100 mg / L.

[0052] Example 2 Preparation of AlPO molecular sieve

[0053] (1) The molar ratio of silicon source, aluminum source and phosphorus source is SiO 2 :Al 2 O 3 :P 2 O 5=0.0:1:1, wherein the phosphorus source is phosphoric acid and ammonium hydrogen phosphate (calculated as P element, the molar ratio is 1:1), the aluminum source is pseudo-boehmite, and the silicon source is white carbon black. The aluminum source, silicon source, and phosphorus source are added with a first template and water for molding, the first template is diethylamine, and the molding method is extrusion pelletizing and spheronization to obtain a spherical precursor A.

[0054] (2) Precursor A is dried to obtain spherical precursor B. The drying temperature is 90° C. and the drying time is 20 h.

[0055] (3) The obtained precursor B is added with a second template agent in a stoichiometric ratio for crystallization, wherein the second template agent is diethylamine, the molar ratio of the first template agent to the second template agent is 0.95:0.05, and the aluminum source (in the form of Al 2 O 3 The ratio of the molar amount of the first template and the molar amount of the second template is 1:0.7. The water content of the precursor B is 10%, the crystallization temperature is 185°C, and the crystallization time is 36h to obtain a molecular sieve.

[0056] (4) The crystallized molecular sieve is washed, filtered, dried and calcined at a temperature of 580°C for 6 hours. The strength of the molecular sieve prepared by this method is 70N / particle, and the static water absorption rate is 32%.

[0057] The prepared molecular sieve is used for dehydrating ethanol to prepare anhydrous ethanol. The water content of the raw ethanol is 5%. The liquid phase adsorption method is adopted. The mass ratio of the raw material to the adsorbent during the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of the ethanol is 99.50% and the water content is 0.5%.

[0058] Example 3 Preparation of SAPO Molecular Sieve

[0059] (1) The molar ratio of silicon source, aluminum source and phosphorus source is SiO 2 :Al 2 O 3 :P 2 O 5 =0.3:1:1, wherein the phosphorus source is phosphoric acid and ammonium hydrogen phosphate (calculated as P element, the molar ratio is 1:1), the aluminum source is pseudo-boehmite, and the silicon source is white carbon black. The aluminum source, silicon source, and phosphorus source are added with a first template and water for molding, the first template is triethylamine, and the molding method is spherical molding to obtain a spherical precursor A.

[0060] (2) Precursor A is dried to obtain spherical precursor B. The drying temperature is 110° C. and the drying time is 12 h.

[0061] (3) The obtained precursor B is added with a second template agent in a stoichiometric ratio for crystallization. The second template agent is triethylamine. The molar ratio of the first template agent to the second template agent is 0.9:0.1. The aluminum source (with Al2 O 3 The ratio of the molar amount of the first template and the molar amount of the second template is 1:2.0, the moisture content of the precursor B is 15%, the crystallization temperature is 190°C, and the crystallization time is 30h to obtain a molecular sieve.

[0062] (4) The crystallized molecular sieve is washed, filtered, dried and calcined at a temperature of 550° C. for 5 h. The strength of the molecular sieve prepared by this method is 75 N / particle, and the static water absorption rate is 32.5%.

[0063] The prepared molecular sieve was used for dehydrating methanol to prepare anhydrous methanol. The water content of the raw methanol was 4.8%. The liquid phase adsorption method was adopted with a raw material to adsorbent mass ratio of 5:1 and an adsorption time of 1 day. After adsorption, the methanol purity was 99.20% and the water content was 0.8%.

[0064] Example 4 Preparation of SAPO Molecular Sieve

[0065] (1) The molar ratio of silicon source, aluminum source and phosphorus source is SiO 2 :Al 2 O 3 :P 2 O 5 =0.5:1:1, wherein the phosphorus source is phosphoric acid, the aluminum source is pseudo-boehmite, and the silicon source is white carbon black. The aluminum source, the silicon source, and the phosphorus source are added with a first template and water for molding, wherein the first template is di-n-propylamine, and the molding method is spheronization molding, to obtain a spherical precursor A.

[0066] (2) Precursor A is dried to obtain spherical precursor B. The drying temperature is 120° C. and the drying time is 9 h.

[0067] (3) The obtained precursor B is added with a second template agent in a stoichiometric ratio for crystallization. The second template agent is di-n-propylamine. The molar ratio of the first template agent to the second template agent is 0.8:0.2. The aluminum source (in the form of Al 2 O 3 The ratio of the molar amount of the first template and the molar amount of the second template is 1:1.5. The water content of the precursor B is 20%, the crystallization temperature is 190°C, and the crystallization time is 24h to obtain a molecular sieve.

[0068] (4) The crystallized molecular sieve is washed, filtered, dried and calcined at a temperature of 550° C. for 4 hours. The strength of the molecular sieve prepared by this method is 65N / particle, and the static water absorption rate is 31%.

[0069] The prepared molecular sieve is used for dehydrating ethanol to prepare anhydrous ethanol. The water content of the raw ethanol is 5%. The liquid phase adsorption method is adopted. The mass ratio of the raw material to the adsorbent during the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of the ethanol is 99.55% and the water content is 0.45%.

[0070] Example 5 Preparation of SAPO Molecular Sieve

[0071] (1) The molar ratio of silicon source, aluminum source and phosphorus source is SiO 2 :Al 2 O 3 :P 2 O 5 =0.4:1:0.9, wherein the phosphorus source is phosphoric acid, the aluminum source is pseudo-boehmite, and the silicon source is silica sol. The aluminum source, silicon source, and phosphorus source are added with a first template and water for molding, wherein the first template is cyclohexylamine, and the molding method is extrusion, spheronization, and pelletization to obtain a spherical precursor A.

[0072] (2) Precursor A is dried to obtain spherical precursor B. The drying temperature is 100° C. and the drying time is 20 h.

[0073] (3) The obtained precursor B is added with a second template agent in a stoichiometric ratio for crystallization. The second template agent is cyclohexylamine. The molar ratio of the first template agent to the second template agent is 0.8:0.2. The aluminum source (in the form of Al 2 O 3 The ratio of the molar amount of the first template and the second template to the molar amount of the first template is 1:1.25. The water content of the precursor B is 20%, the crystallization temperature is 180°C, and the crystallization time is 24h to obtain a molecular sieve.

[0074] (4) The crystallized molecular sieve is washed, filtered, dried and calcined at a temperature of 580°C for 4 hours. The strength of the molecular sieve prepared by this method is 72N / particle, and the static water absorption rate is 30.5%.

[0075] The prepared molecular sieve was used for dehydrating methanol to prepare anhydrous methanol. The water content of the raw methanol was 4.8%. The liquid phase adsorption method was adopted with a raw material to adsorbent mass ratio of 5:1 and an adsorption time of 1 day. After adsorption, the methanol purity was 99.60% and the water content was 0.4%.

[0076] Example 6 Preparation of SAPO Molecular Sieve

[0077] The molecular sieve was prepared according to the method of Example 1, except that the molar ratio of the first template to the second template was 0.7:0.3. The strength of the molecular sieve prepared by this method was 50N / particle, and the static water absorption rate was 30.5%.

[0078] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.98%, water is 200 mg / L, diisopropylamine is 40 mg / L, acetone is 110 mg / L, and other impurities are 142 mg / L.

[0079] Example 7 Preparation of SAPO Molecular Sieve

[0080] The molecular sieve was prepared according to the method of Example 1, except that the molar ratio of the first template to the second template was 0.6:0.4. The strength of the molecular sieve prepared by this method was 45N / particle, and the static water absorption rate was 30.3%.

[0081] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.98%, water is 210 mg / L, diisopropylamine is 39 mg / L, acetone is 118 mg / L, and other impurities are 145 mg / L.

[0082] Example 8 Preparation of SAPO Molecular Sieve

[0083] The molecular sieve was prepared according to the method of Example 1, except that the water content of the precursor B in step (3) was 2%. The strength of the molecular sieve prepared by this method was 63N / particle, and the static water absorption rate was 31.2%.

[0084] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.98%, water is 142 mg / L, diisopropylamine is 36 mg / L, acetone is 96 mg / L, and other impurities are 129 mg / L.

[0085] Example 9 Preparation of SAPO Molecular Sieve

[0086] The molecular sieve was prepared according to the method of Example 1, except that the water content of the precursor B in step (3) was 10%. The strength of the molecular sieve prepared by this method was 50N / particle, and the static water absorption rate was 30.8%.

[0087] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1, and the adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.99%, water is 125 mg / L, diisopropylamine is 34 mg / L, acetone is 81 mg / L, and other impurities are 127 mg / L.

[0088] Example 10 Preparation of SAPO Molecular Sieve

[0089] The molecular sieve was prepared according to the method of Example 1, except that the water content of the precursor B in step (3) was 40%. The strength of the molecular sieve prepared by this method was 40N / particle, and the static water absorption rate was 30.1%.

[0090] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.98%, water is 137 mg / L, diisopropylamine is 38 mg / L, acetone is 95 mg / L, and other impurities are 132 mg / L.

[0091] Comparative Example 1

[0092] The molecular sieve was prepared according to the method of Example 1, except that the molecular sieve powder was first prepared, and then a binder was added to form a spherical molecular sieve. Specifically, the molar ratio of the aluminum source, the silicon source, the phosphorus source, and the template (R) was SiO 2 :Al 2 O 3 :P 2 O 5 :R=0.6:1:0.8:1.2, wherein the phosphorus source is phosphoric acid, the aluminum source is aluminum isopropoxide, the silicon source is white carbon black, and the template is triethylamine. The aluminum source, silicon source, phosphorus source and template are crystallized at a crystallization temperature of 195°C and a crystallization time of 24h to obtain a molecular sieve powder. A binder is added to the molecular sieve powder for rolling and forming, and the binder is alumina, and the addition amount is 30%. After washing and filtering, it is dried and calcined at a calcination temperature of 550°C and a calcination time of 4h. A spherical molecular sieve is obtained.

[0093] The strength of the molecular sieve prepared by this method is 54N / particle, and the static water absorption rate is 22%. The XRD spectrum of the molecular sieve is as follows Figure 3As shown, it can be seen that the XRD spectrum of the molecular sieve shows impurity peaks, which are derived from the added binder and will affect the adsorption performance of the molecular sieve.

[0094] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.97%, water is 300 mg / L, diisopropylamine is 45 mg / L, acetone is 140 mg / L, and other impurities are 160 mg / L.

[0095] Comparative Example 2

[0096] The molecular sieve was prepared according to the method of Example 1, except that the first template was not added in step (1), and only the second template was added in step (3) for crystallization. The aluminum source (in the form of Al 2 O 3 The molar ratio of the first template to the second template is 1:1.2. The strength of the molecular sieve prepared by the method is 45N / particle, and the static water absorption rate is 25%.

[0097] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.95%, water is 450 mg / L, diisopropylamine is 57 mg / L, acetone is 210 mg / L, and other impurities are 175 mg / L.

[0098] Comparative Example 3

[0099] The molecular sieve was prepared according to the method of Example 1, except that the first template was added only in step (1) for crystallization, and the aluminum source (in the form of Al 2 O 3 The molar ratio of the first template to the first template is 1:1.2. The strength of the molecular sieve prepared by the method is 50N / particle, and the static water absorption rate is 27%.

[0100] The prepared molecular sieve is used for dehydrating industrial isopropanol to prepare high-purity isopropanol. The raw material isopropanol has a purity of 99.95%, water is 800 mg / L, diisopropylamine is 60 mg / L, acetone is 240 mg / L, and other impurities are 200 mg / L. The liquid phase adsorption method is adopted. The mass ratio of raw material to adsorbent in the adsorption process is 5:1. The adsorption time is 1 day. After adsorption, the purity of isopropanol is 99.98%, water is 207 mg / L, diisopropylamine is 37 mg / L, acetone is 113 mg / L, and other impurities are 139 mg / L.

[0101] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited thereto. Within the technical concept of the present invention, the technical solution of the present invention can be subjected to a variety of simple modifications, including the combination of various technical features in any other suitable manner, and these simple modifications and combinations should also be regarded as the contents disclosed by the present invention and belong to the protection scope of the present invention.

Claims

1. A method for preparing SAPO or AlPO molecular sieves, include: (1) subjecting a first mixture containing a first template, an aluminum source, a phosphorus source, and an optional silicon source to a molding process to obtain a precursor; (2) subjecting the second mixture containing the precursor and the second template to a crystallization reaction to obtain the SAPO or AlPO molecular sieve.

2. The preparation method according to claim 1, It is characterized in that In step (1), the silicon source is SiO 2 The aluminum source is Al 2 O 3 Phosphorus source is P 2 O 5 The molar ratio of the silicon source, the aluminum source and the phosphorus source is (0-1.0):1.0:(0.8-1.2), preferably (0-0.6):1.0:(0.8-1.0).

3. The preparation method according to claim 1 or 2, It is characterized in that The phosphorus source comprises at least one of phosphoric acid, phosphorous acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate or polyphosphoric acid, preferably selected from phosphoric acid and / or ammonium hydrogen phosphate; and / or The aluminum source comprises at least one of pseudo-boehmite, aluminum hydroxide, aluminum isopropoxide or aluminum oxide, preferably selected from pseudo-boehmite and / or aluminum isopropoxide; and / or The silicon source comprises at least one of white carbon black, silica sol or silica gel, preferably white carbon black; and / or The first template comprises at least one of triethylamine, diethylamine, di-n-propylamine, cyclohexylamine, morpholine or quaternary ammonium base; and / or The second template agent includes at least one of triethylamine, diethylamine, di-n-propylamine, cyclohexylamine, morpholine or quaternary ammonium base; Preferably, the first templating agent is the same as the second templating agent.

4. The preparation method according to any one of claims 1 to 3, It is characterized in that Aluminum source is Al 2 O 3 The ratio of the molar amount of the aluminum source to the sum of the molar amounts of the first template and the second template is 1:(0.7-2.0), preferably 1:(0.8-1.5); Preferably, the molar ratio of the first template to the second template is (0.6-0.95):(0.05-0.4), preferably (0.7-0.95):(0.05-0.3), and more preferably (0.85-0.95):(0.05-0.15).

5. The preparation method according to any one of claims 1 to 4, It is characterized in that The water content of the precursor is 2-40%, preferably 5-30%, and more preferably 10-20%.

6. The preparation method according to any one of claims 1 to 5, It is characterized in that The molding process comprises at least one of spray drying, spheronization or extrusion pelletization and spheronization.

7. The preparation method according to any one of claims 1 to 6, It is characterized in that The temperature of the crystallization reaction is 160-200° C., preferably 165-195° C.; and or Preferably, the crystallization reaction time is 12 to 48 hours, preferably 24 to 36 hours.

8. The preparation method according to any one of claims 1 to 7, It is characterized in that Step (1) further comprises drying the product after the molding process to obtain the precursor; and / or Step (2) further comprises calcining the product after the crystallization reaction to obtain the SAPO or AlPO molecular sieve; Preferably, the drying temperature is 80 to 150°C, preferably 90 to 120°C; Preferably, the drying time is 2 to 24 hours, preferably 8 to 20 hours; Preferably, the calcination temperature is 550-650°C, preferably 550-580°C; Preferably, the calcination treatment time is 2 to 12 hours, preferably 4 to 6 hours.

9. SAPO or AlPO molecular sieve prepared by the preparation method according to any one of claims 1 to 8, Preferably, the strength of the SAPO or AlPO molecular sieve is 40 to 80 N / particle, preferably 65 to 80 N / particle.

10. Use of the SAPO or AlPO molecular sieve prepared by the preparation method according to any one of claims 1 to 8 or the molecular sieve according to claim 1 as an adsorbent or catalyst, Preferably, the SAPO or AlPO molecular sieve is used to remove water and impurities from organic solvents.

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