Preparation process of phosphate silane

Abstract

The invention belongs to the technical field of preparation of phosphate silane, and particularly relates to a preparation process of phosphate silane. Phosphoric acid is encapsulated in a pore channel in situ by utilizing a confinement effect of the pore channel of the MOF, the water content of a system is strictly controlled through vacuum dehydration activation of MIL-101 (Cr)-PO4, the hydrolysis side reaction of phosphate silane caused by the water content is avoided, the purity of a product is improved, a phosphoric acid P-OH bond is activated by a Cr < 3 + > Lewis acid site in an MOF framework, the reaction activity of phosphoric acid is improved, and a silanization reaction is promoted; therefore, the reaction time is shortened. In addition, the silicon carbide micro-channel reactor is adopted, segmented temperature control is achieved, the selectivity of the product is improved, and the purity of the product is further improved. The Ag < + > modified molecular sieve membrane and the MOF material can be recycled, compared with a DMF reagent used in a traditional process, the solvent cost can be well saved, meanwhile, waste salt can be prevented from being generated, and therefore the waste treatment cost is reduced.

Description

Technical Field

[0001] This invention belongs to the field of phosphate ester silane preparation technology, specifically relating to a preparation process for phosphate ester silanes. Background Technology

[0002] The existing processes for preparing phosphate ester silanes have several problems. Using solvents such as DMF to dehydrate the raw materials not only makes subsequent separation difficult but also easily causes solvent residue, affecting product purity. Traditional reaction routes involve numerous side reactions and require the use of acid-binding agents, which not only increases costs but also generates waste salts and other waste products. In the purification process, vacuum distillation is energy-intensive and may lead to product decomposition.

[0003] Based on this, the present invention proposes a preparation process for phosphate ester silanes, hoping to overcome the shortcomings of the prior art. Summary of the Invention

[0004] The purpose of this invention is to address the existing problems by providing a process for preparing phosphate silanes.

[0005] This invention is achieved through the following technical solution:

[0006] A process for preparing a phosphate ester silane includes the following steps:

[0007] S1. Add MIL-101(Cr) to deionized water, add phosphoric acid dropwise under stirring, reflux and then vacuum dry to obtain MIL-101(Cr)-PO4, and then perform vacuum dehydration and activation treatment to obtain activated MIL-101(Cr)-PO4.

[0008] S2. A silicon carbide microchannel reactor is used, with TMCS (trimethylchlorosilane) vapor in the gas phase, THF suspension of phosphoric acid encapsulated in MOF in the liquid phase, and MOF support in the solid phase, to carry out gas-liquid-solid three-phase micro-interface catalytic condensation reaction.

[0009] S3. Pass the reaction solution into supercritical CO2 to elute the adsorbed HCl. The desorbed MOF is returned to S1 for recycling.

[0010] S4. Filter the desorbed reaction solution and wash the resulting wet salt with solvent.

[0011] S5. Take the filtered liquid, add the extraction solvent to extract, and let it stand to separate the layers.

[0012] S6. Collect the supernatant after extraction and perform vacuum distillation on it to obtain crude phosphate silane;

[0013] S7. The crude phosphate ester silane obtained by separation is passed through Ag +The modified molecular sieve membrane is used for deep dechlorination. The dechlorinated retentate is then introduced into a short-path molecular distillation apparatus for distillation to obtain the final phosphate silane product.

[0014] Further, the mass-to-volume ratio of MIL-101(Cr) to deionized water in step S1 is 1g:25~30mL;

[0015] The mass ratio of MIL-101 (Cr) to phosphoric acid is 5:3;

[0016] The reflux temperature is 75~85℃, and the reflux time is 20~26h;

[0017] The vacuum drying temperature is 75~85℃, and the vacuum drying pressure is 10. -3 mbar;

[0018] The vacuum dehydration activation temperature is 120℃ and the pressure is 10. -3 mbar, time is 2~3h, final moisture content ≤10ppm.

[0019] Furthermore, the channel diameter of the silicon carbide microchannel reactor described in step S2 is 500 μm;

[0020] The method for preparing the MOF-encapsulated phosphoric acid THF suspension is as follows: the activated MIL-101(Cr)-PO4 is mixed with THF (tetrahydrofuran) to prepare a THF suspension with a concentration of 200 g / L, and the suspension is subjected to ultrasonic dispersion treatment for 30 to 40 min.

[0021] Furthermore, the gas-liquid-solid three-phase micro-interface catalytic condensation described in step S2 is controlled in stages: the first stage is 0~15s, the channel temperature is 25℃, and the TMCS vapor injection rate is 10mL / min; the second stage is 15~30s, the channel temperature is increased to 40℃, the TMCS vapor injection rate is increased to 15mL / min, and the residence time is 30s.

[0022] Furthermore, the elution and adsorption temperature in step S3 is 60°C and the pressure is 15 MPa.

[0023] Furthermore, the solvent mentioned in step S4 is MTBE (methyl tert-butyl ether), and the washing is performed 2 to 3 times.

[0024] Furthermore, the extractant mentioned in step S5 is MTBE, and the amount of extractant used is 20-30% of the total mass of the filtrate.

[0025] Furthermore, in step S6, during the vacuum distillation stage, n-hexane is introduced to distill off hexamethyldisiloxane at a lower temperature, thereby obtaining high-purity phosphate silane.

[0026] Furthermore, the Ag mentioned in step S7 + The preparation of modified molecular sieve membranes includes the following steps:

[0027] (1) Place the α-Al2O3 ceramic membrane tube into the dielectric barrier discharge plasma (DBD) reactor, introduce a mixture of acrylic acid and argon gas with a volume ratio of 1:9, and treat with 300W for 10~15min;

[0028] (2) Dissolve 2-methylimidazole and 2-mercaptobenzimidazole in methanol at a molar ratio of 9:1 and stir to obtain a mixed solution of ligands;

[0029] AgNO3 and Zn(NO3)2·6H2O were dissolved in methanol at a molar ratio of 1:19 and stirred until dissolved to obtain a mixed metal solution.

[0030] The metal solution is added dropwise to the ligand solution, and stirred at 200-300 rpm for 20-30 min to obtain the precursor solution;

[0031] (3) Immerse the ceramic membrane tube treated in step (1) into the precursor solution, vertically pull it at a speed of 5 cm / min, dry it at room temperature to form an initial seed layer, and then put it into a stainless steel reactor with a polytetrafluoroethylene liner. Add the precursor solution, use microwave-assisted synthesis, and react at 80℃ and 300W power for 30 min to grow ZIF-8 crystals on the substrate to form a film.

[0032] (4) The ZIF-8 / α-Al2O3 molecular sieve membrane was immersed in a 0.01M sodium ascorbate solution, and the membrane surface was scanned with an ultraviolet laser to carry out a photocatalytic reduction reaction;

[0033] (5) Immerse the membrane tube after the photocatalytic reduction reaction in a 0.1M 1,2-ethylenedithiol ethanol solution and treat it at 60~70℃ for 0.5~1h. After treatment, rinse the surface of the membrane tube with ethanol and then purge it under a nitrogen atmosphere.

[0034] Furthermore, the distillation conditions described in step S7 are: a temperature of 130°C and a pressure of 0.01 mbar.

[0035] Furthermore, the main reaction formula for the preparation of the phosphate ester silane is:

[0036] .

[0037] In this invention, MOF and MIL-101 (Cr) are the same material.

[0038] The present invention has the following advantages over the prior art:

[0039] 1. This invention utilizes the confinement effect of MOF channels to encapsulate phosphate in situ within the channels. Vacuum dehydration activation with MIL-101(Cr)-PO4 is employed to strictly control the moisture content of the system, avoiding water-induced hydrolysis of phosphate ester silanes, thus improving product purity. The Cr content in the MOF framework is also reduced. 3+ Lewis acid sites activate the P-OH bond of phosphate, enhancing the reactivity of phosphoric acid, promoting silanization, and improving reaction efficiency, thereby shortening the reaction time. Furthermore, this invention employs a silicon carbide microchannel reactor with segmented temperature control, improving product selectivity and further enhancing product purity. Finally, Ag... + Modified molecular sieve membranes are used for deep dechlorination to meet the stringent requirements of high-end lithium battery electrolytes for high chlorine content. Thiol coordination end-capping is used to form a covalent network, increasing Ag content. + The membrane's stability and recyclability effectively reduce costs.

[0040] 2. The MOF material of the present invention can be recycled. Compared with the traditional process using DMF reagent, it can save solvent costs and avoid the generation of waste salt, thereby reducing the cost of waste disposal. Detailed Implementation

[0041] To further explain the present invention, the following specific embodiments are described.

[0042] Example 1

[0043] A process for preparing a phosphate ester silane includes the following steps:

[0044] S1. Add MIL-101(Cr) to deionized water at a mass-to-volume ratio of 1g:25mL. Add phosphoric acid dropwise while stirring, maintaining a mass ratio of MIL-101(Cr) to phosphoric acid of 5:3. Reflux at 75℃ for 20 hours, then at 75℃ for 10... -3 MIL-101(Cr)-PO4 was obtained by vacuum drying under mbar pressure, followed by vacuum dehydration and activation treatment at 120°C and 1000°C. -3 mbar, time 2h, final moisture content ≤10ppm, to obtain activated MIL-101(Cr)-PO4;

[0045] S2. The activated MIL-101(Cr)-PO4 was mixed with THF (tetrahydrofuran) to prepare a THF suspension with a concentration of 200 g / L. The suspension was then ultrasonically dispersed for 30 min to obtain a THF suspension of MOF-encapsulated phosphoric acid.

[0046] A silicon carbide microchannel reactor (channel diameter 500 μm) was used, with TMCS (trimethylchlorosilane) vapor in the gas phase, THF suspension of phosphoric acid encapsulated in MOF in the liquid phase, and MOF support in the solid phase to carry out gas-liquid-solid three-phase micro-interface catalytic condensation reaction.

[0047] The reaction was controlled in stages: the first stage lasted 5 seconds, the channel temperature was 25°C, and the TMCS vapor injection rate was 10 mL / min; the second stage lasted 15 seconds, the channel temperature was increased to 40°C, the TMCS vapor injection rate was increased to 15 mL / min, and the residence time was 30 seconds.

[0048] S3. Pass the reaction solution into supercritical CO2, 60℃, 15MPa to elute the adsorbed HCl, and return the desorbed MOF to S1 for recycling.

[0049] S4. The desorbed reaction solution is filtered, and the resulting wet salt is washed twice with MTBE (methyl tert-butyl ether).

[0050] S5. Take the filtered filtrate, add 20% of the total mass of the filtrate as the extraction agent MTBE for extraction, and let it stand to separate into layers;

[0051] S6. Collect the supernatant after extraction and treat it with vacuum distillation to obtain crude phosphate silane. In the vacuum distillation stage, n-hexane is introduced to distill off hexamethyldisiloxane at a lower temperature, thereby obtaining high-purity phosphate silane.

[0052] S7. The crude phosphate ester silane obtained by separation is passed through Ag + The modified molecular sieve membrane was used for deep dechlorination. The dechlorinated retentate was introduced into a short-path molecular distillation apparatus for distillation at a temperature of 130°C and a pressure of 0.01 mbar to obtain the final phosphate silane product.

[0053] The Ag mentioned + The preparation of modified molecular sieve membranes includes the following steps:

[0054] (1) Place the α-Al2O3 ceramic membrane tube into the dielectric barrier discharge plasma (DBD) reactor, introduce a mixture of acrylic acid and argon gas with a volume ratio of 1:9, and treat with 300W for 10min;

[0055] (2) Dissolve 2-methylimidazole and 2-mercaptobenzimidazole in methanol at a molar ratio of 9:1 and stir to obtain a mixed solution of ligands;

[0056] AgNO3 and Zn(NO3)2·6H2O were dissolved in methanol at a molar ratio of 1:19 and stirred until dissolved to obtain a mixed metal solution.

[0057] The metal solution was added dropwise to the ligand solution and stirred at 200 rpm for 20 min to obtain the precursor solution.

[0058] (3) Immerse the ceramic membrane tube treated in step (1) into the precursor solution, vertically pull it at a speed of 5 cm / min, dry it at room temperature to form an initial seed layer, and then put it into a stainless steel reactor with a polytetrafluoroethylene liner. Add the precursor solution, use microwave-assisted synthesis, and react at 80℃ and 300W power for 30 min to grow ZIF-8 crystals on the substrate to form a film.

[0059] (4) The ZIF-8 / α-Al2O3 molecular sieve membrane was immersed in a 0.01M sodium ascorbate solution, and the membrane surface was scanned with an ultraviolet laser to carry out a photocatalytic reduction reaction;

[0060] (5) Immerse the membrane tube after the photocatalytic reduction reaction in a 0.1M 1,2-ethylenedithiol ethanol solution and treat it at 60℃ for 0.5h. After treatment, rinse the surface of the membrane tube with ethanol and then purge it under a nitrogen atmosphere.

[0061] Example 2

[0062] A process for preparing a phosphate ester silane includes the following steps:

[0063] S1. Add MIL-101(Cr) to deionized water at a mass-to-volume ratio of 1g:28mL. Add phosphoric acid dropwise while stirring, maintaining a mass ratio of MIL-101(Cr) to phosphoric acid of 5:3. Reflux at 80℃ for 23 hours, then at 80℃ for 10... -3 MIL-101(Cr)-PO4 was obtained by vacuum drying under mbar pressure, followed by vacuum dehydration and activation treatment at 120°C and 1000°C. -3 mbar, time 2.5h, final moisture content ≤10ppm, to obtain activated MIL-101(Cr)-PO4;

[0064] S2. The activated MIL-101(Cr)-PO4 was mixed with THF (tetrahydrofuran) to prepare a THF suspension with a concentration of 200 g / L. The suspension was then ultrasonically dispersed for 35 min to obtain a THF suspension of MOF-encapsulated phosphoric acid.

[0065] A silicon carbide microchannel reactor (channel diameter 500 μm) was used, with TMCS (trimethylchlorosilane) vapor in the gas phase, THF suspension of phosphoric acid encapsulated in MOF in the liquid phase, and MOF support in the solid phase to carry out gas-liquid-solid three-phase micro-interface catalytic condensation reaction.

[0066] The reaction was controlled in stages: the first stage lasted 10 seconds, the channel temperature was 25°C, and the TMCS vapor injection rate was 10 mL / min; the second stage lasted 20 seconds, the channel temperature was increased to 40°C, the TMCS vapor injection rate was increased to 15 mL / min, and the residence time was 30 seconds.

[0067] S3. Pass the reaction solution into supercritical CO2, 60℃, 15MPa to elute the adsorbed HCl, and return the desorbed MOF to S1 for recycling.

[0068] S4. The desorbed reaction solution is filtered, and the resulting wet salt is washed twice with MTBE (methyl tert-butyl ether).

[0069] S5. Take the filtered filtrate, add 25% of the total mass of the filtrate as the extraction agent MTBE for extraction, and let it stand to separate into layers;

[0070] S6. Collect the supernatant after extraction and treat it with vacuum distillation to obtain crude phosphate silane. In the vacuum distillation stage, n-hexane is introduced to distill off hexamethyldisiloxane at a lower temperature, thereby obtaining high-purity phosphate silane.

[0071] S7. The crude phosphate ester silane obtained by separation is passed through Ag + The modified molecular sieve membrane was used for deep dechlorination. The dechlorinated retentate was introduced into a short-path molecular distillation apparatus for distillation at a temperature of 130°C and a pressure of 0.01 mbar to obtain the final phosphate silane product.

[0072] The Ag mentioned + The preparation of modified molecular sieve membranes includes the following steps:

[0073] (1) Place the α-Al2O3 ceramic membrane tube into the dielectric barrier discharge plasma (DBD) reactor, introduce a mixture of acrylic acid and argon gas with a volume ratio of 1:9, and treat with 300W for 12min;

[0074] (2) Dissolve 2-methylimidazole and 2-mercaptobenzimidazole in methanol at a molar ratio of 9:1 and stir to obtain a mixed solution of ligands;

[0075] AgNO3 and Zn(NO3)2·6H2O were dissolved in methanol at a molar ratio of 1:19 and stirred until dissolved to obtain a mixed metal solution.

[0076] The metal solution was added dropwise to the ligand solution, and the mixture was stirred at 250 rpm for 25 min to obtain the precursor solution.

[0077] (3) Immerse the ceramic membrane tube treated in step (1) into the precursor solution, vertically pull it at a speed of 5 cm / min, dry it at room temperature to form an initial seed layer, and then put it into a stainless steel reactor with a polytetrafluoroethylene liner. Add the precursor solution, use microwave-assisted synthesis, and react at 80℃ and 300W power for 30 min to grow ZIF-8 crystals on the substrate to form a film.

[0078] (4) The ZIF-8 / α-Al2O3 molecular sieve membrane was immersed in a 0.01M sodium ascorbate solution, and the membrane surface was scanned with an ultraviolet laser to carry out a photocatalytic reduction reaction;

[0079] (5) Immerse the membrane tube after the photocatalytic reduction reaction in a 0.1M 1,2-ethylenedithiol ethanol solution and treat it at 65℃ for 0.7h. After treatment, rinse the surface of the membrane tube with ethanol and then purge it under a nitrogen atmosphere.

[0080] Example 3

[0081] A process for preparing a phosphate ester silane includes the following steps:

[0082] S1. Add MIL-101(Cr) to deionized water at a mass-to-volume ratio of 1g:30mL. Add phosphoric acid dropwise while stirring, maintaining a mass ratio of MIL-101(Cr) to phosphoric acid of 5:3. Reflux at 85℃ for 26 hours, then at 85℃ for 10... -3 MIL-101(Cr)-PO4 was obtained by vacuum drying under mbar pressure, followed by vacuum dehydration and activation treatment at 120°C and 1000°C. -3 mbar, time 3h, final moisture content ≤10ppm, to obtain activated MIL-101(Cr)-PO4;

[0083] S2. The activated MIL-101(Cr)-PO4 was mixed with THF (tetrahydrofuran) to prepare a THF suspension with a concentration of 200 g / L. The suspension was then ultrasonically dispersed for 40 min to obtain a THF suspension of MOF-encapsulated phosphoric acid.

[0084] A silicon carbide microchannel reactor (channel diameter 500 μm) was used, with TMCS (trimethylchlorosilane) vapor in the gas phase, THF suspension of phosphoric acid encapsulated in MOF in the liquid phase, and MOF support in the solid phase to carry out gas-liquid-solid three-phase micro-interface catalytic condensation reaction.

[0085] The reaction was controlled in stages: the first stage lasted 15 seconds, the channel temperature was 25°C, and the TMCS vapor injection rate was 10 mL / min; the second stage lasted 30 seconds, the channel temperature was raised to 40°C, the TMCS vapor injection rate was increased to 15 mL / min, and the residence time was 30 seconds.

[0086] S3. Pass the reaction solution into supercritical CO2, 60℃, 15MPa to elute the adsorbed HCl, and return the desorbed MOF to S1 for recycling.

[0087] S4. The desorbed reaction solution is filtered, and the resulting wet salt is washed three times with MTBE (methyl tert-butyl ether).

[0088] S5. Take the filtered filtrate, add 30% of the total mass of the filtrate as the extraction agent MTBE for extraction, and let it stand to separate into layers;

[0089] S6. Collect the supernatant after extraction and treat it with vacuum distillation to obtain crude phosphate silane. In the vacuum distillation stage, n-hexane is introduced to distill off hexamethyldisiloxane at a lower temperature, thereby obtaining high-purity phosphate silane.

[0090] S7. The crude phosphate ester silane obtained by separation is passed through Ag + The modified molecular sieve membrane was used for deep dechlorination. The dechlorinated retentate was introduced into a short-path molecular distillation apparatus for distillation at a temperature of 130°C and a pressure of 0.01 mbar to obtain the final phosphate silane product.

[0091] The Ag mentioned + The preparation of modified molecular sieve membranes includes the following steps:

[0092] (1) Place the α-Al2O3 ceramic membrane tube into the dielectric barrier discharge plasma (DBD) reactor, introduce a mixture of acrylic acid and argon gas with a volume ratio of 1:9, and treat with 300W for 15min;

[0093] (2) Dissolve 2-methylimidazole and 2-mercaptobenzimidazole in methanol at a molar ratio of 9:1 and stir to obtain a mixed solution of ligands;

[0094] AgNO3 and Zn(NO3)2·6H2O were dissolved in methanol at a molar ratio of 1:19 and stirred until dissolved to obtain a mixed metal solution.

[0095] The metal solution was added dropwise to the ligand solution, and the mixture was stirred at 300 rpm for 30 min to obtain the precursor solution.

[0096] (3) Immerse the ceramic membrane tube treated in step (1) into the precursor solution, vertically pull it at a speed of 5 cm / min, dry it at room temperature to form an initial seed layer, and then put it into a stainless steel reactor with a polytetrafluoroethylene liner. Add the precursor solution, use microwave-assisted synthesis, and react at 80℃ and 300W power for 30 min to grow ZIF-8 crystals on the substrate to form a film.

[0097] (4) The ZIF-8 / α-Al2O3 molecular sieve membrane was immersed in a 0.01M sodium ascorbate solution, and the membrane surface was scanned with an ultraviolet laser to carry out a photocatalytic reduction reaction;

[0098] (5) Immerse the membrane tube after the photocatalytic reduction reaction in a 0.1M 1,2-ethylenedithiol ethanol solution and treat it at 70℃ for 1h. After treatment, rinse the surface of the membrane tube with ethanol and then purge it under a nitrogen atmosphere.

[0099] Comparative Example 1

[0100] Compared with Example 2, Comparative Example 1 omits the vacuum dehydration and activation treatment in step S1, while the other steps are the same as in Example 2.

[0101] Comparative Example 2

[0102] Compared with Example 2, Comparative Example 2 replaced the staged controlled reaction with a single condition: 35°C, TMCS 12.5 mL / min, retention time 30 s, and other steps were the same as in Example 2.

[0103] Comparative Example 3

[0104] Compared with Example 2, Comparative Example 3 shows that Ag in step S7... + The modified molecular sieve membrane was replaced with a commercially available ordinary ZIF-8 molecular sieve membrane (Jiangsu Xianfeng Nanomaterials Technology Co., Ltd.), and the other steps were the same as in Example 2.

[0105] The yields of the products in each example and comparative example were calculated by weighing, and the purity of the products was tested by high performance liquid chromatography.

[0106] The test results are shown in Table 1 below.

[0107] Table 1

[0108] Yield (%) Product purity (%) Example 1 86.5 99.5 Example 2 86.5 99.6 Example 3 86.4 99.5 Comparative Example 1 72.3 95.1 Comparative Example 2 78.4 97.3 Comparative Example 3 86.0 98.0

[0109] As can be seen from Table 1 above, the product yields and purity of Examples 1-3 are significantly higher than those of Comparative Examples 1-3, indicating that the vacuum dehydration activation, staged micro-reaction, and Ag of the present invention are effective. + The use of modified molecular sieve membranes can effectively ensure the purity and yield of the product.

[0110] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A process for preparing phosphate ester silanes, characterized in that, Includes the following steps: S1. Add MIL-101(Cr) to deionized water, add phosphoric acid dropwise under stirring, reflux and then vacuum dry to obtain MIL-101(Cr)-PO4, and then perform vacuum dehydration and activation treatment to obtain activated MIL-101(Cr)-PO4. S2. A silicon carbide microchannel reactor is used, with TMCS vapor in the gas phase, THF suspension of phosphoric acid encapsulated in MOF in the liquid phase, and MOF support in the solid phase, to carry out gas-liquid-solid three-phase micro-interface catalytic condensation reaction. S3. Pass the reaction solution into supercritical CO2 to elute the adsorbed HCl. The desorbed MOF is returned to S1 for recycling. S4. Filter the desorbed reaction solution and wash the resulting wet salt with solvent. S5. Take the filtered liquid, add the extraction solvent to extract, and let it stand to separate the layers. S6. Collect the supernatant after extraction and perform vacuum distillation on it to obtain crude phosphate silane; S7. The crude phosphate ester silane obtained by separation is passed through Ag + The modified molecular sieve membrane is used for deep dechlorination. The dechlorinated retentate is then introduced into a short-path molecular distillation apparatus for distillation to obtain the final phosphate silane product.

2. The preparation process of a phosphate ester silane according to claim 1, characterized in that, The mass-to-volume ratio of MIL-101(Cr) to deionized water in step S1 is 1g:25~30mL; The mass ratio of MIL-101 (Cr) to phosphoric acid is 5:3; The reflux temperature is 75~85℃, and the reflux time is 20~26h; The vacuum drying temperature is 75~85℃, and the vacuum drying pressure is 10. -3 mbar; The vacuum dehydration activation temperature is 120℃ and the pressure is 10. -3 mbar, time is 2~3h, final moisture content ≤10ppm.

3. The preparation process of a phosphate ester silane according to claim 1, characterized in that, The silicon carbide microchannel reactor described in step S2 has a channel diameter of 500 μm; The method for preparing the MOF-encapsulated phosphoric acid THF suspension is as follows: the activated MIL-101(Cr)-PO4 is mixed with THF to prepare a THF suspension with a concentration of 200 g / L, and the suspension is subjected to ultrasonic dispersion treatment for 30 to 40 min. The gas-liquid-solid three-phase micro-interface catalytic condensation reaction is controlled in stages: the first stage is 0~15s, the channel temperature is 25℃, the TMCS vapor injection rate is 10mL / min; the second stage is 15~30s, the channel temperature is raised to 40℃, the TMCS vapor injection rate is increased to 15mL / min, and the residence time is 30s.

4. The preparation process of a phosphate ester silane according to claim 1, characterized in that, The elution and adsorption temperature in step S3 is 60°C and the pressure is 15 MPa.

5. The preparation process of a phosphate ester silane according to claim 1, characterized in that, The solvent used in step S4 is MTBE, and the washing is performed 2 to 3 times.

6. The preparation process of a phosphate ester silane according to claim 1, characterized in that, The extractant mentioned in step S5 is MTBE, and the amount of extractant used is 20-30% of the total mass of the filtrate.

7. The preparation process of a phosphate ester silane according to claim 1, characterized in that, In step S6, during the vacuum distillation stage, n-hexane is introduced to distill off hexamethyldisiloxane at a lower temperature, thereby obtaining high-purity phosphate silane.

8. The preparation process of a phosphate ester silane according to claim 1, characterized in that, The Ag mentioned in step S7 + The preparation of modified molecular sieve membranes includes the following steps: (1) Place the α-Al2O3 ceramic membrane tube into the dielectric barrier discharge plasma reactor, introduce a mixture of acrylic acid and argon gas with a volume ratio of 1:9, and treat with 300W for 10~15min; (2) Dissolve 2-methylimidazole and 2-mercaptobenzimidazole in methanol at a molar ratio of 9:1 and stir to obtain a mixed solution of ligands; AgNO3 and Zn(NO3)2·6H2O were dissolved in methanol at a molar ratio of 1:19 and stirred until dissolved to obtain a mixed metal solution. The metal solution is added dropwise to the ligand solution, and stirred at 200-300 rpm for 20-30 min to obtain the precursor solution; (3) Immerse the ceramic membrane tube treated in step (1) into the precursor solution, vertically pull it at a speed of 5 cm / min, dry it at room temperature to form an initial seed layer, and then put it into a stainless steel reactor with a polytetrafluoroethylene liner. Add the precursor solution, use microwave-assisted synthesis, and react at 80℃ and 300W power for 30 min to grow ZIF-8 crystals on the substrate to form a film. (4) The ZIF-8 / α-Al2O3 molecular sieve membrane was immersed in a 0.01M sodium ascorbate solution, and the membrane surface was scanned with an ultraviolet laser to carry out a photocatalytic reduction reaction; (5) Immerse the membrane tube after the photocatalytic reduction reaction in a 0.1M 1,2-ethylenedithiol ethanol solution and treat it at 60~70℃ for 0.5~1h. After treatment, rinse the surface of the membrane tube with ethanol and then purge it under a nitrogen atmosphere.

9. The preparation process of a phosphate ester silane according to claim 1, characterized in that, The distillation conditions described in step S7 are: temperature 130℃ and pressure 0.01mbar.

10. The preparation process of a phosphate ester silane according to claim 1, characterized in that, The main reaction formula for the preparation of the phosphate ester silane is: 。

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