WO2017133301A1

WO2017133301A1 - New type of sapo molecular sieve and method for synthesis thereof

Info

Publication number: WO2017133301A1
Application number: PCT/CN2016/106380
Authority: WO
Inventors: 王德花; 田鹏; 刘中民; 郜贝贝; 杨淼; 向骁
Original assignee: 中国科学院大连化学物理研究所
Priority date: 2016-02-04
Filing date: 2016-11-18
Publication date: 2017-08-10
Also published as: CN107032363B; CN107032363A

Abstract

Provided are a SAPO molecular sieve having CHA and GME intergrowth crystal phases, and a method for synthesizing same. The feature of broad peaks and sharp peaks coexisting is apparent in the XRD diffraction spectrogram of the SAPO molecular sieve, the inorganic framework thereof having the chemical composition (Si_xAl_yP_z)O₂, wherein x, y, and z represent the mole fractions of Si, Al, and P, respectively, having the ranges of x=0.01 to 0.28, y=0.35 to 0.55, and z=0.28 to 0.50, respectively, and x+y+z=1. The molecular sieve may serve as a catalyst for an acid catalysis reaction, such as a methanol-to-olefins reaction; a reductive elimination reaction is selected for NO_x, and also may be used for the adsorption and isolation of N₂, CH₄, and CO₂.

Description

A new type of SAPO molecular sieve and its synthesis method

Technical field

The invention belongs to the field of SAPO molecular sieves, and specifically relates to a novel type of SAPO molecular sieve and a synthetic method thereof.

Background technique

The silicoaluminophosphate molecular sieve (SAPO) series molecular sieve was developed by UCC in 1984 (US4440871) and is a microporous crystal composed of three tetrahedral units of SiO ₂ , AlO ₂ ^- and PO ₂ ⁺ . Since the skeleton has a negative charge, there are equilibrium cations outside the skeleton, so it has cation exchange performance. When the outer cation of the skeleton is H ⁺ , the molecular sieve has an acidic center, so it will possess acid-catalyzed reaction performance. The active component of phosphorus aluminosilicate molecular sieve as a catalyst has been used in fields such as refining and petrochemicals, such as catalytic cracking, hydrocracking, isomerization, aromatic alkylation, and conversion of oxygenates.

In general, the synthesis of SAPO molecular sieves requires organic amine/ammonium as a structure directing agent, which is synthesized by hydrothermal or solvothermal methods. Innovations in synthetic methods and the choice of templating agents have a critical impact on the control of product structure and performance. Studies have shown that the double template method (co-SDA) is a promising synthesis method for synthesizing new materials such as silicoalumino, aluminum phosphate and silicoaluminophosphate, which has attracted wide interest of researchers.

The series of novel molecular sieves synthesized by the invention exhibits the characteristics of broad peaks and peaks coexisting, and the XRD diffraction spectrum thereof is in the literature (Microporous and Mesoporous Materials, 30 (1999) 335-346; the official website of the International Molecular Sieve Association http:// www.iza-structure.org/databases/Catalog/ABC_6.pdf ) The spectra of silicoalulites with GME/CHA symbiotic structure are similar. We analyzed that this kind of molecular sieve is a new type of SAPO molecular sieve with GME/CHA symbiotic structure. With the relative proportion of GME and CHA two phases, the individual peak positions in the XRD diffraction spectrum of molecular sieve will shift and the relative intensity will change. Gmelinite (IUPAC Code GME) is a natural silica-alumina zeolite. The skeleton is deposited in AABBAABB(A). Its typical structure is characterized by a large 12-membered ring channel interconnected with a 8-membered ring to form a multi-dimensional Tunnel system. In general, GME tends to form a eutectic material with CHA (such as chabazite), and the skeleton of CHA is deposited in the form of AABBCCAABBCC (A), both of which belong to the ABC-6 family. Currently, all known natural GME zeolites are such symbiotic types with CHA. Due to the existence of symbiotic defects in the GME framework, the 12-membered ring channel is blocked, which in turn affects its adsorption performance, such as its inability to adsorb larger volumes of molecules such as cyclohexane. Louis D. Rollnarn first synthesized a pure phase GME with a clear 12-membered ring using polymer DABCO as a template (Journal of the American Chemical Society, 1978, 100(10): 3097-3100). Later, U.S. Patent 5,283,047 reported a pure phase GME structure containing transition metal, named ECR-26. It is believed that the addition of transition metal will eliminate the CHA eutectic phase and make the 12-member ring unblocked, showing better n-hexane adsorption performance. To date, there have been no reports on molecular sieves for synthesizing the GME structure composed of SAPO and the CHA/GME eutectic structure.

Summary of the invention

It is an object of the present invention to provide a novel class of SAPO molecular sieves having GME and CHA eutectic structures.

According to an embodiment of the present invention, there is provided a SAPO molecular sieve having a GME and a CHA eutectic structure, the X-ray diffraction pattern of the molecular sieve containing at least a diffraction peak as shown in Table 1 below.

Table 1

According to another embodiment of the present invention, there is provided a novel SAPO molecular sieve having a GME and a CHA eutectic structure, the X-ray diffraction pattern of the molecular sieve containing at least a diffraction peak as shown in Table 2 below.

Table 2

According to another embodiment of the present invention, there is provided a novel SAPO molecular sieve having a GME and CHA eutectic structure, the X-ray diffraction pattern of the molecular sieve containing at least a diffraction peak as shown in Table 3 below.

table 3

The inorganic skeleton of the molecular sieve has the following chemical composition: (Si _x Al _y P _z )O ₂ , wherein: x, y, and z represent the molar fractions of Si, Al, and P, respectively, and the ranges are x=0.01 to 0.28, respectively. , y = 0.35 to 0.55, z = 0.28 to 0.50, and x + y + z = 1. Preferably, x = 0.07 to 0.20, y = 0.43 to 0.52, z = 0.30 to 0.45, and x + y + z = 1. The anhydrous chemical composition of the molecular sieve in the presence of the templating agent can be expressed as: mR1·nR3·(Si _x Al _y P _z )O ₂ , wherein: R1 is diisopropanolamine or diethanolamine, and R3 is trimethylamine; m is the (Si _x Al _y P _z) moles of R1 templating agent per mole of O _2, n is the number of moles of O ₂ in R3 templating agent per mole of _{_{_{(Si x Al y P z)}}} , m = 0.01 ~ 0.08, n=0.01～0.20; x, y, and z represent the molar fractions of Si, Al, and P, respectively, and the ranges are x=0.01 to 0.28, y=0.35 to 0.55, z=0.28 to 0.50, and x+y+z. =1.

A further object of the present application is to provide a method of synthesizing a novel class of SAPO molecular sieves.

According to an embodiment of the present application, there is provided a method of synthesizing a molecular sieve of the above type, comprising the steps of:

a) Deionized water, silicon source, aluminum source, phosphorus source, templating agent R1 and templating agent R2 are mixed in proportion to obtain an initial gel mixture having the following molar ratio:

SiO ₂ /Al ₂ O ₃ =0.15 to 2.0;

P ₂ O ₅ /Al ₂ O ₃ =0.5 to 1.5;

H ₂ O/Al ₂ O ₃ = 8 to 40;

R1/Al ₂ O ₃ = 5 to 20;

R2/Al ₂ O ₃ = 0.1 to 1.5;

R1 is diisopropanolamine (DIPA) or diethanolamine (DEOA); R2 is trimethylamine (TMA), benzyltrimethylammonium chloride (BTACl), benzyltrimethylammonium hydroxide (BTAOH) Any one or any combination of any ones.

b) the initial gel mixture obtained is charged into a high-pressure synthesis kettle, sealed, heated to 160-220 ° C, and crystallized under autogenous pressure for 5 to 72 hours;

c) After the crystallization is completed, the solid product is separated, washed, and dried to obtain the molecular sieve.

Wherein, the silicon source is any silicon-containing substance that can be used for molecular sieve synthesis; the aluminum source is any aluminum-containing substance that can be used for molecular sieve synthesis; and the phosphorus source is any which can be used for molecular sieve synthesis. A substance containing phosphorus.

Preferably, the silicon source in step a) is selected from one or more of silica sol, active silica, orthosilicate, metakaolin; the aluminum source is selected from the group consisting of aluminum salt, activated alumina, and thin One or more of diaspore, alkoxy aluminum, metakaolin; the phosphorus source is selected from one or more of orthophosphoric acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate, organic phosphide, and phosphorus oxide. Kind. Preferably, the crystallization process in step b) can be carried out either statically or dynamically.

Preferably, said step a) initial gel mixture has SiO ₂ /Al ₂ O ₃ = 0.25-1.8.

Preferably, said step a) initially in the gel mixture P ₂ O ₅ /Al ₂ O ₃ = 0.8 to 1.5.

Preferably, the step a) initial gel mixture has an R1/Al ₂ O ₃ = 6.0-18.

Preferably, said step a) initial gel mixture has R2/Al ₂ O ₃ = 0.25-1.0.

The organic templating agent benzyltrimethylammonium chloride (BTACl) and benzyltrimethylammonium hydroxide (BTAOH) in R2 are decomposed in the molecular sieve synthesis to form trimethylamine and enter the pore cage of the molecular sieve.

In the above method for synthesizing molecular sieves, when R1 is diisopropanolamine and the crystallization temperature is 160-195 ° C, it is advantageous to synthesize a molecular sieve having the XRD diffraction spectrum shown in Table 1; when R1 is diisopropanol Amine, when the crystallization temperature is 195-220 ° C, it is advantageous to synthesize the molecular sieve with the XRD diffraction spectrum shown in Table 2; when R1 is diethanolamine, the molar ratio of R1/R2 is 4-16, which is beneficial to the synthesis of Table 1. The molecular sieve; when R1 is diethanolamine and the R1/R2 molar ratio is 16.1-60, it is advantageous to synthesize a molecular sieve having the XRD diffraction spectrum shown in Table 2.

A further object of the present application is to provide a catalyst for removing NO _x selective reduction reaction, it was 400 ~ 700 ℃ was air calcined in the above-described molecular sieves and / or molecular sieve synthesized according to the method described above.

A further object of the present application is to provide a catalyst for the conversion of an oxygenate to an olefin which is obtained by calcining the above molecular sieve and/or molecular sieve synthesized according to the above method in air at 400 to 700 °C.

A further object of the present application is to provide an adsorbent for adsorption separation and separation of carbon dioxide from methane and/or nitrogen, which is obtained by calcining the above molecular sieve and/or molecular sieve synthesized according to the above method in air at 400 to 700 ° C. of. For the adsorptive separation of carbon dioxide from methane and/or nitrogen, it can be used for the separation of CO ₂ from CH ₄ , the separation of CO ₂ from N ₂ , and the separation of CO ₂ and CH ₄ + N ₂ mixed gas.

The beneficial effects that can be produced by the present invention include:

(1) A new class of SAPO molecular sieves was obtained.

(2) The prepared molecular sieve can be used as a catalyst for acid-catalyzed reaction and conversion of oxygenate to olefin The hydrocarbon reacts and exhibits good catalytic properties.

(3) The prepared molecular sieve exhibits excellent gas adsorption separation performance.

DRAWINGS

1, 3 and 5 are XRD patterns of the synthesized products in Example 1, Example 2 and Example 3, respectively. 2, 4 and 6 are scanning electron micrographs (SEM) of the synthesized products in Example 1, Example 2 and Example 3, respectively.

detailed description

The invention is further illustrated below in conjunction with the examples. It is to be understood that the examples are not intended to limit the scope of the invention. The experimental methods in the following examples which do not specify the specific conditions are usually carried out according to conventional conditions or according to the conditions recommended by the manufacturer. Unless otherwise specified, the raw materials used in this application are purchased commercially and used without special treatment.

Unless otherwise specified, the test conditions of this application are as follows:

The elemental composition was determined using a Philips Magix 2424 X-ray fluorescence analyzer (XRF).

X-ray powder diffraction phase analysis (XRD) was carried out using an X'Pert PRO X-ray diffractometer from the PANalytical Company of the Netherlands, a Cu target, a Kα radiation source (λ = 0.15418 nm), a voltage of 40 kV, and a current of 40 mA.

The specific surface area and pore size distribution of the samples were determined using a Micromeritics ASAP Model 2020 physical adsorber. Before the analysis, the sample was preheated at 350 ° C for 6 h, and the free volume of the sample tube was measured with He as the medium. When the sample was analyzed, the adsorption and desorption measurements were carried out at a liquid nitrogen temperature (77 K) using nitrogen as an adsorption gas. The specific surface area of the material was determined using the BET formula; the total pore volume of the material was calculated using the amount of adsorption of N ₂ at a relative pressure (P/P ₀ ) of 0.99. The micropore surface area and micropore volume were calculated by the t-plot method. When calculated, the cross-sectional area of the N ₂ molecule was taken to be 0.162 nm ² .

The SEM morphology analysis was performed using a Hitachi (SU8020) type scanning electron microscope.

Carbon nuclear magnetic resonance ( ¹³ C MAS NMR) analysis was performed using a Varian Infinity plus 400 WB solid-state nuclear magnetic spectrum analyzer with a BBO MAS probe operating at a magnetic field strength of 9.4T.

The CHN elemental analysis was performed using a Vario EL Cube elemental analyzer made in Germany.

The invention is described in detail below by means of examples, but the invention is not limited to the examples.

Example 1

The molar ratio of each raw material and the crystallization conditions are shown in Table 4. The specific batching process is as follows: the diisopropanolamine solid is melted into a liquid solvent in a 60 ° C water bath, and the pseudoboehmite (Al ₂ O ₃ mass percentage 72.5%) and diisopropanolamine (mass percentage) Mixing 99%), stirring, then adding silica sol (SiO ₂ mass percentage 30.04%), stirring evenly, then adding phosphoric acid (H ₃ PO ₄ mass percentage 85%) dropwise, stirring evenly, then adding water And the solution of trimethylamine was stirred to form a gel, and the gel was transferred to a stainless steel reaction vessel. After the reaction kettle was placed in an oven, the temperature was programmed to crystallization at 180 ° C for 48 h. After the crystallization was completed, the solid product was centrifuged, washed, and dried in air at 100 ° C to obtain a sample of the molecular sieve raw powder. The sample was subjected to XRD analysis, and the peak shape exhibited characteristics of broad peaks and peaks. The XRD diffraction pattern is shown in Fig. 1, and the XRD diffraction data is shown in Table 5. After the sample was calcined and the template was removed, the specific surface area and pore volume were measured. The sample had a high BET specific surface area (657 m ² g ^-1 ) and a large pore volume (0.3 cm ³ g ^-1 ), according to t-plot. The micropore specific surface area and micropore volume calculated by the method were 596 m ² g ^-1 and 0.26 cm ³ g ^{-1 , respectively} .

The scanning electron micrograph of the obtained sample is shown in Fig. 2. It can be seen that the morphology of the obtained sample is a hexagonal plate-like layered layer, and the surface of the crystal grain is rough, and the particle size ranges from 3 to 5 μm.

Example 2

The molar ratio of each raw material and the crystallization conditions are shown in Table 4. The specific batching process is the same as in the first embodiment. The solvent is diethanolamine. After the reaction kettle is placed in an oven, the temperature is programmed to be crystallization at 200 ° C for 36 h. After the crystallization was completed, the solid product was centrifuged, washed, and dried in air at 100 ° C to obtain a sample of the molecular sieve raw powder. The sample was subjected to XRD analysis, and the peak shape exhibited characteristics of broad peaks and peaks. The XRD diffraction pattern is shown in Fig. 3, and the XRD diffraction data is shown in Table 6. After the sample was calcined and the template was removed, the specific surface area and pore volume were measured. The sample had a high BET specific surface area of 617 m ² g ^-1 and a large pore volume of 0.28 cm ³ g ^-1 , which was calculated according to the t-plot method. The specific pore surface area and micropore volume were 553 m ² g ^-1 and 0.27 cm ³ g ^{-1 , respectively} .

The scanning electron micrograph of the obtained sample is shown in Fig. 4. It can be seen that the morphology of the obtained sample is a layered stacked disc having a particle size ranging from 3 to 5 μm.

Example 3

The molar ratio of each raw material and the crystallization conditions are shown in Table 4. The specific compounding process was the same as in Example 1. The solvent was diisopropanolamine. After the reaction kettle was placed in an oven, the temperature was programmed to crystallization at 190 ° C for 48 hours. After the crystallization was completed, the solid product was centrifuged, washed, and dried in air at 100 ° C to obtain a sample of the molecular sieve raw powder. The sample was subjected to XRD analysis, and the peak shape exhibited characteristics of broad peaks and peaks. The XRD diffraction pattern is shown in Fig. 5, and the XRD diffraction data is shown in Table 7. After the sample was calcined and the template was removed, the specific surface area and pore volume were measured. The sample had a high BET specific surface area of 632 m ² g ^-1 and a large pore volume of 0.29 cm ³ g ^-1 , which was calculated according to the t-plot method. The specific pore surface area and micropore volume were 574 m ² g ^-1 and 0.28 cm ³ g ^{-1 , respectively} .

The scanning electron micrograph of the obtained sample is shown in Fig. 6. It can be seen that the morphology of the obtained sample is a lamellar layered layer having a particle size ranging from 3 to 5 μm.

Table 4 Molecular sieve synthesis ingredients and crystallization conditions table

* is static crystallization synthesis, the rest is dynamic crystallization synthesis. (Static is to put the synthesis kettle directly in the oven to stand still, dynamic crystallization is to stir the synthetic gel by the rotation of the kettle body, the rotation of the synthesis kettle is driven by the motor placed outside the oven, the rotation speed can be Adjusted by the inverter.)

Table 5 XRD results of the sample of Example 1

Table 6 XRD results of the sample of Example 2

Table 7 XRD results of the sample of Example 3

Example 4

The specific proportion of ingredients and crystallization conditions are shown in Table 4. The specific batching process is the same as in Example 1.

The synthesized samples were subjected to XRD analysis, and representative data results are shown in Table 8.

Scanning electron micrographs showed that the morphology of the obtained sample was similar to that of the sample of Example 1.

Table 8 XRD results of the sample of Example 4

Example 5

The synthesized samples were subjected to XRD analysis, and representative data results are shown in Table 9.

Table 9 XRD results of the sample of Example 5

Example 6-8

The synthesized samples were subjected to XRD analysis, and the results of XRD data of Examples 6, 7, and 8 were close to those of Tables 5, 8, and 9, respectively.

The content of GME crystal phase in the silica-phosphorus aluminum molecular sieves provided in Examples 1 and 4-8 was compared with the diffraction spectra of the different ratios of GME/CHA symbiotic silicoaluminosilicate crystal phases given on the official website of the International Molecular Sieve Association. It is significantly higher than the CHA phase.

Example 9

The specific proportion of ingredients and crystallization conditions are shown in Table 4. The specific batching process is the same as in Example 2.

The synthesized samples were subjected to XRD analysis, and representative data results are shown in Table 10.

Scanning electron micrographs showed that the morphology of the obtained sample was similar to that of the sample of Example 2.

Table 10 XRD results of the sample of Example 9

Example 10

The synthesized samples were subjected to XRD analysis, and representative data results are shown in Table 11.

Table 11 XRD results of the sample of Example 10

Example 11-14

The synthesized samples were subjected to XRD analysis, and the results of XRD data of Examples 11, 12, 13, and 14 were similar to Tables 6, 10, and 11, respectively.

The content of CHA crystal phase in the silica-phosphorus aluminum molecular sieves provided in Examples 2 and 9-14 was compared with the diffraction spectra of the different ratios of GME/CHA symbiotic silicoaluminosilicate crystal phases given on the official website of the International Molecular Sieve Association. It is higher than the GME crystal phase.

Example 15

The specific proportion of ingredients and crystallization conditions are shown in Table 4. The specific batching process is the same as in Example 3.

The synthesized samples were subjected to XRD analysis, and representative data results are shown in Table 12.

Scanning electron micrographs showed that the morphology of the obtained sample was similar to that of Example 3.

Table 12 XRD results of the sample of Example 15

Example 16

The synthesized samples were subjected to XRD analysis, and representative data results are shown in Table 13.

Table 13 XRD results of the sample of Example 16

Example 17-19

The synthesized samples were subjected to XRD analysis, and the results of XRD data of Examples 17, 18, and 19 were close to those of Tables 7, 12, and 13, respectively.

The content of CHA crystal phase in the silica-phosphorus aluminum molecular sieves provided in Examples 3 and 15-19 is compared with the diffraction spectra of the different ratios of GME/CHA symbiotic silicoaluminosilicate crystal phases given on the official website of the International Molecular Sieve Association. It should be close to the content of the GME crystal phase.

Example 20

¹³ C MAS NMR analysis of the original powder samples of Examples 1-10 was carried out by comparison with ¹³ C MAS NMR standard spectra of diisopropanolamine, diethanolamine and trimethylamine, and it was found that diisopropanolamine was used as a solvent. The sample has both a resonance peak of diisopropanolamine and trimethylamine, and the sample synthesized by using diethanolamine as a solvent has a resonance peak of diethanolamine and trimethylamine. Quantitative analysis was performed based on the NMR peaks characteristic of the two substances, and the ratio of the two was determined.

The CHN elemental analysis of the original powder samples of Examples 1-10 was carried out by XRF analysis of the bulk elemental composition of the molecular sieve product. Based on the results of CHN elemental analysis, XRF and ¹³ C MAS NMR analysis, the composition of the molecular sieve raw powder is shown in Table 14:

Table 14

实施例Example	样品原粉组成Sample raw powder composition
11	0.05DIPA·0.08TMA(Si_0.121Al_0.480P_0.399)O₂ 0.05DIPA·0.08TMA (Si _0.121 Al _0.480 P _0.399 )O ₂
22	0.07DIPA·0.02TMA(Si_0.118Al_0.470P_0.412)O₂ 0.07DIPA·0.02TMA(Si _0.118 Al _0.470 P _0.412 )O ₂
33	0.02DEOA·0.20TMA(Si_0.231Al_0.427P_0.342)O₂ 0.02DEOA·0.20TMA(Si _0.231 Al _0.427 P _0.342 )O ₂
44	0.03DIPA·0.10TMA(Si_0.134Al_0.483P_0.383)O₂ 0.03DIPA·0.10TMA(Si _0.134 Al _0.483 P _0.383 )O ₂
55	0.025DIPA·0.15TMA(Si_0.180Al_0.468P_0.352)O₂ 0.025DIPA·0.15TMA(Si _0.180 Al _0.468 P _0.352 )O ₂
66	0.029DIPA·0.056TMA(Si_0.110Al_0.481P_0.409)O₂ 0.029DIPA·0.056TMA(Si _0.110 Al _0.481 P _0.409 )O ₂
77	0.04DEOA·0.18TMA(Si_0.242Al_0.401P_0.357)O₂ 0.04DEOA·0.18TMA(Si _0.242 Al _0.401 P _0.357 )O ₂
88	0.08DEOA·0.20TMA(Si_0.280Al_0.440P_0.280)O₂ 0.08DEOA·0.20TMA(Si _0.280 Al _0.440 P _0.280 )O ₂
99	0.01DEOA·0.01TMA(Si_0.010Al_0.490P_0.500)O₂ 0.01DEOA·0.01TMA(Si _0.010 Al _0.490 P _0.500 )O ₂
1010	0.031DIPA·0.058TMA(Si_0.130Al_0.483P_0.387)O₂ 0.031DIPA·0.058TMA(Si _0.130 Al _0.483 P _0.387 )O ₂

The original powder samples of Examples 1-10 were separately ground and pressed with potassium bromide and subjected to FT-IR characterization. They all showed a characteristic vibration absorption peak attributed to the double six-membered ring at 637 cm ^-1 . There is a double six-membered ring in the sample.

Example 21

The sample obtained in Example 1 was subjected to copper exchange in a 0.01 mol/L copper nitrate solution at a solid-liquid ratio of 1:30. After the exchange of the samples calcined at 650 ℃ temperature 2h, after removal of the template agent for selective reduction of NH ₃ reacts with NO _x removal catalyst properties were characterized. The specific experimental procedures and conditions are as follows: After calcination, the sample was sieved, and 0.1 g of a 60 to 80 mesh sample was weighed and mixed with 0.4 g of quartz sand (60 to 80 mesh), and charged into a fixed bed reactor. The reaction was started by nitrogen activation at 600 ° C for 40 min, then the temperature was lowered to 120 ° C, and the temperature was programmed to 550 ° C. The reaction raw material gas was: NO: 500 ppm, NH ₃ : 500 ppm, O ₂ : 5%, H ₂ O: 5%, gas flow rate: 300 ml/min. The reaction product was subjected to online FTIR analysis using a Bruker Tensor 27 instrument. The reaction results showed that the conversion of NO was 55% at 150 ° C, and the conversion of NO was greater than 90% in the wide temperature range of 200-550 ° C. Similarly, Example 2 and Example 3 Samples obtained after the same as in Example 1, treated sample also showed a better removal of NO _x selective reduction of catalytic performance.

Example 22

The sample obtained in Example 2 was calcined at 550 ° C for 4 hours, and then tableted and crushed to 20 to 40 mesh. 1.0 g of the sample was weighed into a fixed bed reactor, and MTO reaction evaluation was performed. The reaction was carried out by a nitrogen gas activation at 550 ° C for 1 hour and then cooling to 450 ° C. The methanol was carried by nitrogen, the nitrogen flow rate was 40 ml/min, and the methanol weight space velocity was 4.0 h ^-1 . The reaction product was analyzed by on-line gas chromatography (Varian 3800, FID detector, capillary column PoraPLOT Q-HT). The results are shown in Table 15.

Table 15 Results of methanol conversion to olefins in samples

a: the methanol conversion rate is 100% of the time (dimethyl ether is regarded as the reaction raw material);

b: highest (ethylene + propylene) selectivity at 100% methanol conversion.

Example 23

The sample obtained in Example 3 was calcined at 550 ° C for 4 hours. The adsorption isotherms of CO ₂ , CH ₄ , N ₂ were measured by a Micromeritics Gemini VII 2390 apparatus. The sample was pretreated for 4 hours at 350 ° C and N ₂ atmosphere before the measurement. The adsorption test was at a constant temperature of 25 ° C and a pressure of 101 kPa. The results of adsorption separation are shown in Table 16. Similarly, the samples obtained in Example 1 and Example 2 also exhibited higher CO ₂ adsorption capacity and high CO ₂ /CH ₄ adsorption separation ratio.

Table 16 CO ₂ /CH ₄ adsorption separation results of samples

The present application is disclosed in the above preferred embodiments, but is not intended to limit the scope of the claims. Any one of ordinary skill in the art can make various possible changes and modifications without departing from the spirit of the present application. The scope should be determined by the scope defined by the claims of the present application.

The present application claims priority to Chinese Patent Application No. 201610081120.8, filed on Feb. 4, 2016, which is hereby incorporated by reference in its entirety.

Claims

A silicoaluminophosphate (SAPO) molecular sieve having a CHA and GME symbiotic phase, characterized in that the X-ray diffraction pattern of the molecular sieve contains at least the following diffraction peaks:
A silicoaluminophosphate (SAPO) molecular sieve having a CHA and GME symbiotic phase, characterized in that the X-ray diffraction pattern of the molecular sieve contains at least the following diffraction peaks:
A silicoaluminophosphate (SAPO) molecular sieve having a CHA and GME symbiotic phase, characterized in that the X-ray diffraction pattern of the molecular sieve contains at least the following diffraction peaks:
The molecular sieve according to any one of claims 1 to 3, wherein the inorganic skeleton of the molecular sieve has a chemical composition of: (Si x Al y P z )O 2 , wherein: x, y, and z respectively represent Si The molar fractions of Al and P are in the range of x=0.01 to 0.28, y=0.35 to 0.55, z=0.28 to 0.50, and x+y+z=1.
The molecular sieve according to any one of claims 1 to 3, wherein the anhydrous chemical composition of the molecular sieve in the presence of the templating agent can be expressed as: mR1.nR3.(Si x Al y P z )O 2 , wherein : R1 is diisopropanolamine or diethanolamine, R3 is trimethylamine; m is the number of moles of R1 templating agent per mole of (Si x Al y P z )O 2 , n is per mole (Si x Al y P z The number of moles of R3 templating agent in O 2 , m=0.01-0.08, n=0.01-0.20; x, y, z respectively represent the molar fraction of Si, Al, P, respectively, and the range is x=0.01-0.28, y = 0.35 to 0.55, z = 0.28 to 0.50, and x + y + z = 1.
A method of synthesizing the molecular sieve according to any one of claims 1 to 5, comprising the steps of:

a) Deionized water, silicon source, aluminum source, phosphorus source, templating agent R1 and templating agent R2 are mixed in proportion to obtain an initial gel mixture having the following molar ratio:

SiO 2 /Al 2 O 3 =0.15 to 2.0;

P 2 O 5 /Al 2 O 3 =0.5 to 1.5;

H 2 O/Al 2 O 3 = 8 to 40;

R1/Al 2 O 3 = 5 to 20;

R2/Al 2 O 3 = 0.1 to 1.5;

Wherein R1 is diisopropanolamine (DIPA) or diethanolamine (DEOA); R2 is trimethylamine (TMA), benzyltrimethylammonium chloride (BTACl), benzyltrimethylammonium hydroxide (BTAOH) Any one or a mixture of any of them.

b) the initial gel mixture obtained in step a) is charged into a high pressure synthesis kettle, sealed, heated to 160-220 ° C, and crystallized under autogenous pressure for 5 to 72 hours;

c) After the crystallization is completed, the solid product is separated, washed, and dried to obtain the molecular sieve.
The method according to claim 6, wherein the silicon source in step a) is selected from one or more of silica sol, active silica, orthosilicate, metakaolin; One or more selected from the group consisting of aluminum salt, activated alumina, pseudoboehmite, alkoxy aluminum, metakaolin; the phosphorus source is selected from the group consisting of orthophosphoric acid, ammonium hydrogen phosphate, ammonium dihydrogen phosphate, and organic phosphorus Chemical One or more of substances and phosphorus oxides.
Process according to claim 6, characterized in that the crystallization process in step b) is carried out under static or dynamic conditions.
The method according to claim 6, wherein said step a) initial gel mixture has R1/Al 2 O 3 = 6.0 to 18.
The method according to claim 6, wherein said step a) initial gel mixture has R2/Al 2 O 3 = 0.25 to 1.0.
One kind of NO x selective reduction catalyst removal reaction, consisting of a molecular sieve claimed in any one of the claim or method according to any one of claims 6-10 synthesized molecular sieve at 400 to 700 °C is obtained by roasting in air.
A catalyst for the conversion of an oxygenate to an olefin, the molecular sieve synthesized by the molecular sieve according to any one of claims 1 to 5 or the method according to any one of claims 6 to 10, 400 to 700 °C is obtained by roasting in air.
A CH 4 /CO 2 , N 2 /CO 2 adsorption separation material synthesized by the molecular sieve according to any one of claims 1 to 5 or the method according to any one of claims 6 to 10. The molecular sieve is obtained by calcination in air at 400 to 700 °C.