Preparation method and application of H-type ZSM-5 molecular sieve catalyst

Abstract

The invention provides a preparation method of an H-type ZSM-5 molecular sieve catalyst, which comprises the following steps: pickling a sodium-type ZSM-5 molecular sieve with an acidic aqueous solution at 80 DEG C for 2 hours, with the mass fraction of acid in the acidic aqueous solution being 5-10%, and the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve being (5-20): 1, and after acid pickling, repeatedly washing with deionized water to be neutral, and drying at 120 DEG C for 4 hours to obtain the H-type ZSM-5 molecular sieve catalyst. The invention also provides application of the H-type ZSM-5 molecular sieve catalyst. Through cooperative regulation and control of the liquid-solid ratio and the acid concentration, the H-type ZSM-5 molecular sieve catalyst has a proper acid site, so that the H-type ZSM-5 molecular sieve catalyst can play a role in adsorbing a basic catalyst and can also play a role in catalyzing a ring-opening polymerization reaction in synthesis of polyether, hydroxyl groups of polyether are closer to theoretical hydroxyl groups, and the synthesis efficiency of polyether is improved. In addition, metal ion residues of the basic catalyst in the polyether product are reduced.

Description

Technical Field

[0001] This invention relates to the technical field of molecular sieve catalysts, specifically to a method for preparing an H-type ZSM-5 molecular sieve catalyst and its application. Background Technology

[0002] The existing common method for converting H-type ZSM-5 molecular sieves involves multiple exchanges of sodium-type ZSM-5 molecular sieves with ammonium salts, followed by sequential filtration, washing, drying, and calcination. This method is cumbersome. Obtaining H-type ZSM-5 molecular sieves through inorganic acid exchange can easily damage catalyst activity. Furthermore, there is currently no research on the regulation of acidic sites in H-type ZSM-5 molecular sieves for both adsorbing alkaline catalysts and catalyzing ring-opening polymerization. Summary of the Invention

[0003] To overcome the shortcomings of the prior art, the present invention aims to provide a method for preparing H-type ZSM-5 molecular sieve catalyst. Through the synergistic regulation of liquid-solid ratio and acid concentration, the H-type ZSM-5 molecular sieve catalyst has suitable acidic sites, thereby enabling it to both adsorb alkaline catalysts and catalyze ring-opening polymerization reactions in the synthesis of polyethers. This makes the hydroxyl groups of the polyether closer to the theoretical hydroxyl groups and also helps to reduce the residual metal ions of alkaline catalysts in the polyether products.

[0004] To solve the above problems, the technical solution adopted by the present invention is as follows: A method for preparing an H-type ZSM-5 molecular sieve catalyst includes the following steps: Sodium-type ZSM-5 molecular sieves were acid-washed with an acidic aqueous solution at a temperature of 80°C for 2 hours. The mass fraction of acid in the acidic aqueous solution was 5%-10%, and the volume (mL) of the acidic aqueous solution was 5-20:1 compared with the mass (g) of the sodium-type ZSM-5 molecular sieve. After pickling, wash repeatedly with deionized water until neutral; After washing, the catalyst was dried at 120°C for 4 hours to obtain the H-type ZSM-5 molecular sieve catalyst.

[0005] In some possible implementations, the acid in the acidic aqueous solution is selected from at least one of phosphoric acid, nitric acid, and sulfuric acid.

[0006] In some possible implementations, the acid in the acidic aqueous solution has a mass fraction of 5%-7.5%, and the acid in the acidic aqueous solution is phosphoric acid.

[0007] In some possible implementations, the volume (mL) of the acidic aqueous solution is 5-15 times the mass (g) of the sodium-type ZSM-5 molecular sieve.

[0008] This application also provides an application of the H-type ZSM-5 molecular sieve catalyst obtained by the preparation method described above. The H-type ZSM-5 molecular sieve catalyst is used to catalyze the ring-opening polymerization reaction of an alcohol initiator and an epoxide under alkaline catalyst to obtain an intermediate, and then to catalyze the addition of a new epoxide to the system to perform ring-opening polymerization to obtain a polyether product. The H-type ZSM-5 molecular sieve catalyst is also used to adsorb alkaline catalyst to reduce the residual metal ions in the polyether product.

[0009] Compared with the prior art, the beneficial effects of the present invention are as follows: In this application, by synergistically controlling the liquid-to-solid ratio and acid concentration of the acidic aqueous solution and the sodium-type ZSM-5 molecular sieve, the resulting H-type ZSM-5 molecular sieve catalyst possesses suitable acidic sites. This allows it to both adsorb alkaline catalysts and catalyze ring-opening polymerization in the synthesis of polyethers, resulting in polyether hydroxyl groups that are closer to the theoretical hydroxyl groups. Furthermore, it helps reduce the residual metal ions of the alkaline catalyst in the polyether product. In addition, the preparation method provided in this application does not require high-temperature calcination or repeated exchange operations, thus improving operational simplicity.

[0010] The present invention will be further described in detail below with reference to specific embodiments. Detailed Implementation

[0011] The technical solutions in the embodiments of this application will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. Based on the embodiments in this application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of this application.

[0012] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

[0013] The following describes some embodiments of the present invention in detail. Unless otherwise specified, the following embodiments and features can be combined with each other.

[0014] One embodiment of this application provides a method for preparing an H-type ZSM-5 molecular sieve catalyst, the preparation method comprising the following steps.

[0015] The sodium-type ZSM-5 molecular sieve was acid-washed with an acidic aqueous solution at a temperature of 80°C for 2 hours. The acid mass fraction of the acid in the acidic aqueous solution was 5%-10%, and the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 5-20:1.

[0016] After pickling, wash repeatedly with deionized water until neutral.

[0017] After washing, the catalyst was dried at 120°C for 4 hours to obtain the H-type ZSM-5 molecular sieve catalyst.

[0018] In this application, by synergistically controlling the liquid-to-solid ratio and acid concentration of the acidic aqueous solution and the sodium-type ZSM-5 molecular sieve, the resulting H-type ZSM-5 molecular sieve catalyst possesses suitable acidic sites. This allows it to both adsorb alkaline catalysts and catalyze ring-opening polymerization in the synthesis of polyethers, resulting in polyether hydroxyl groups that are closer to the theoretical hydroxyl groups. Furthermore, it helps reduce the residual metal ions of the alkaline catalyst in the polyether product. In addition, the preparation method provided in this application does not require high-temperature calcination or repeated exchange operations, thus improving operational simplicity.

[0019] In some embodiments, the acid in the acidic aqueous solution is selected from at least one of phosphoric acid, nitric acid, and sulfuric acid.

[0020] Preferably, the acid in the acidic aqueous solution has a mass fraction of 5%-7.5%, and the acid in the acidic aqueous solution is phosphoric acid.

[0021] Preferably, the volume (mL) of the acidic aqueous solution is 5-15 times the mass (g) of the sodium-type ZSM-5 molecular sieve.

[0022] Another embodiment of this application provides an application of an H-type ZSM-5 molecular sieve catalyst, which is obtained by the above-described preparation method. The H-type ZSM-5 molecular sieve catalyst is used in a system where, after a ring-opening polymerization reaction of an alcohol initiator and an epoxide is catalyzed by an alkaline catalyst to obtain an intermediate, the intermediate is further added to the epoxide to undergo ring-opening polymerization to obtain a polyether product. The H-type ZSM-5 molecular sieve catalyst is also used to adsorb the alkaline catalyst to reduce residual metal ions in the polyether product.

[0023] The following is a detailed description of the embodiments.

[0024] Example 1 Preparation of H-type ZSM-5 molecular sieve catalysts First, 2g of sodium-type ZSM-5 molecular sieve was acid-washed with a 5% (w / w) phosphoric acid aqueous solution at 80℃ for 2 hours. The volume of the phosphoric acid aqueous solution used was 10mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 5:1. After acid washing, the sieve was repeatedly washed with deionized water until neutral. After washing, the sieve was dried at 120℃ for 4 hours to remove moisture, thus obtaining the H-type ZSM-5 molecular sieve catalyst.

[0025] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.09g of potassium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 88g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0026] Add 1.47g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 70℃, and then add 120g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes. Control the reaction temperature to maintain 70±2℃ to obtain crude 1,4-butynediol block polyether.

[0027] The crude polyether was cooled to 60°C, 15g of deionized water was added, and the mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0028] The finished product of Example 1 was tested, and the results were: hydroxyl value 384.2 mg KOH / g, and potassium and sodium ion content 10.1 ppm.

[0029] Example 2 Preparation of H-type ZSM-5 molecular sieve catalysts First, 2g of sodium-type ZSM-5 molecular sieve was acid-washed with a 5% (w / w) sulfuric acid aqueous solution at 80℃ for 2 hours, using 10mL of sulfuric acid aqueous solution. Therefore, the volume (mL) of the acidic aqueous solution was 5:1 compared to the mass (g) of the sodium-type ZSM-5 molecular sieve. After acid washing, the sieve was repeatedly washed with deionized water until neutral. Following washing, it was dried at 120℃ for 4 hours to remove moisture, yielding the H-type ZSM-5 molecular sieve catalyst.

[0030] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.09g of potassium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 88g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0031] Add 1.47g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 70℃, and then add 120g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes, and obtain crude 1,4-butynediol block polyether.

[0032] The crude polyether was cooled to 60°C, 15g of deionized water was added, and the mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0033] The finished product of Example 2 was tested, and the results were: hydroxyl value 386.2 mgKOH / g, potassium and sodium ion content 15.3ppm.

[0034] Example 3 Preparation of H-type ZSM-5 molecular sieve catalysts First, 2g of sodium-type ZSM-5 molecular sieve was acid-washed with a 5% (by mass) nitric acid aqueous solution at a temperature of 80℃ for 2 hours. The volume of the nitric acid aqueous solution was 10mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 5:1. After acid washing, the sieve was repeatedly washed with deionized water until neutral. After washing, the sieve was dried at 120℃ for 4 hours to remove moisture and obtain the H-type ZSM-5 molecular sieve catalyst.

[0035] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.09g of potassium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 88g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0036] 1.47g of H-type ZSM-5 molecular sieve catalyst was added to the intermediate, the temperature was raised to 70℃, and then 120g of propylene oxide was added dropwise. After the addition was completed, the aging reaction was continued until the pressure no longer changed, and crude 1,4-butynediol block polyether was obtained.

[0037] The crude polyether was cooled to 60°C, 15g of deionized water was added, and the mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0038] The finished product of Example 3 was tested, and the results were: hydroxyl value 390 mgKOH / g, potassium and sodium ion content 20.2ppm.

[0039] Comparing Examples 1 to 3, it can be seen that, under the same conditions, the hydroxyl value of the polyether product treated with phosphoric acid is closer to the theoretical hydroxyl value (381.6 mgKOH / g), and the potassium and sodium ion content is lower.

[0040] Example 4 Preparation of H-type ZSM-5 molecular sieve catalysts First, 4g of sodium-type ZSM-5 molecular sieve was acid-washed with a 5% (phosphoric acid) aqueous solution at a temperature of 80℃ for 2 hours. The volume of the acidic aqueous solution was 40mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 10:1. After acid washing, the sieve was repeatedly washed with deionized water until neutral. After washing, the sieve was dried at 120℃ for 4 hours to remove moisture and obtain H-type ZSM-5 molecular sieve catalyst.

[0041] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.20g of potassium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 176g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0042] Add 3.7g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 80℃, and then add 232g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes, and obtain crude 1,4-butynediol block polyether.

[0043] The crude polyether was cooled to 60°C, and 37g of deionized water was added. The mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0044] The finished product of Example 4 was tested, and the results were: hydroxyl value 383.0 mg KOH / g, and potassium and sodium ion content 5.1 ppm.

[0045] Example 5 Preparation of H-type ZSM-5 molecular sieve catalysts First, 4g of sodium-type ZSM-5 molecular sieve was acid-washed with a 7.5% (by mass) phosphoric acid aqueous solution at 80℃ for 2 hours. The volume of the phosphoric acid aqueous solution used was 40mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 10:1. After acid washing, the sieve was repeatedly washed with deionized water until neutral. After washing, it was dried at 120℃ for 4 hours to remove moisture, thus obtaining the H-type ZSM-5 molecular sieve catalyst.

[0046] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.20g of potassium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 176g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0047] Add 3.7g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 80℃, and then add 232g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes, and obtain crude 1,4-butynediol block polyether.

[0048] The crude polyether was cooled to 60°C, and 37g of deionized water was added. The mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0049] The finished product of Example 5 was tested, and the results were: hydroxyl value 382.8 mg KOH / g, and potassium and sodium ion content 3.5 ppm.

[0050] Example 6 Preparation of H-type ZSM-5 molecular sieve catalysts First, 4g of sodium-type ZSM-5 molecular sieve was acid-washed with a 10% (phosphoric acid) aqueous solution at a temperature of 80℃ for 2 hours. The volume of the acidic aqueous solution was 40mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 10:1. After acid washing, the solution was repeatedly washed with deionized water until neutral. After washing, the solution was dried at 120℃ for 4 hours to remove moisture, thus obtaining the H-type ZSM-5 molecular sieve catalyst for later use.

[0051] Preparation of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.20g of potassium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 176g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0052] Add 3.7g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 80℃, and then add 232g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes, and obtain crude 1,4-butynediol block polyether.

[0053] The crude polyether was cooled to 60°C, and 37g of deionized water was added. The mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0054] The finished product of Example 6 was tested, and the results were: hydroxyl value 390.6 mg KOH / g, and potassium and sodium ion content 12.0 ppm.

[0055] Comparing the test results of Examples 4 to 6, it can be seen that when the mass fraction of acid in the acidic aqueous solution is 5%-7.5%, the hydroxyl value of the corresponding polyether is closer to the theoretical value, and the potassium and sodium ion content in the polyether product is lower.

[0056] Comparative Example 1 and Comparative Example 2 By changing the mass fraction of acid in the phosphoric acid aqueous solution in Example 4 to 2.5% and 15% respectively, while keeping other conditions unchanged, Comparative Example 1 and Comparative Example 2 were obtained.

[0057] The finished products of Comparative Examples 2 and 3 were tested, and the results were as follows: Comparative Example 1: hydroxyl value 392.3 mg KOH / g, potassium and sodium ion content 13.6 ppm; Comparative Example 2: hydroxyl value 395.6 mg KOH / g, potassium and sodium ion content 16.2 ppm. Comparing the results of the above examples and comparative examples, it can be seen that excessively high or low acid concentrations may reduce the catalytic activity of the H-type ZSM-5 molecular sieve catalyst, and may also lead to an increase in potassium and sodium ion content. Therefore, to achieve both adsorption of metal ions and improved catalytic activity, the acid concentration needs to be limited to a predetermined range.

[0058] Example 7 Preparation of H-type ZSM-5 molecular sieve catalysts First, 8g of sodium-type ZSM-5 molecular sieve was acid-washed with a 7.5% (phosphoric acid) aqueous solution at a temperature of 80℃ for 2 hours. The volume of the acidic aqueous solution was 120mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 15:1. After acid washing, the solution was repeatedly washed with deionized water until neutral. After washing, the solution was dried at 120℃ for 4 hours to remove moisture and obtain the H-type ZSM-5 molecular sieve catalyst.

[0059] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.43g of sodium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 352g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0060] Add 7.8g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 90℃, and then add 348g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes, and obtain crude 1,4-butynediol block polyether.

[0061] The crude polyether was cooled to 60°C, 78g of deionized water was added, and the mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0062] The finished product of Example 7 was tested, and the results were: hydroxyl value 382.6 mg KOH / g, and potassium and sodium ion content 6.8 ppm.

[0063] Example 8 Preparation of H-type ZSM-5 molecular sieve catalysts First, 8g of sodium-type ZSM-5 molecular sieve was acid-washed with a 10% (mass fraction) phosphoric acid aqueous solution at 80℃ for 2 hours. The volume of the phosphoric acid aqueous solution used was 160mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 20:1. After acid washing, the sieve was repeatedly washed with deionized water until neutral. After washing, it was dried at 120℃ for 4 hours to remove moisture, thus obtaining the H-type ZSM-5 molecular sieve catalyst.

[0064] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.43g of sodium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 352g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0065] Add 7.8g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 90℃, and then add 348g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes, and obtain crude 1,4-butynediol block polyether.

[0066] The crude polyether was cooled to 60°C, 78g of deionized water was added, and the mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0067] The finished product of Example 8 was tested, and the results were: hydroxyl value 388.6 mg KOH / g, and potassium and sodium ion content 11.2 ppm.

[0068] Comparing Examples 7 and 8, it can be seen that increasing the volume (mL) of the acidic aqueous solution, the mass (g) of the sodium-type ZSM-5 molecular sieve, and the mass fraction of the acid are all detrimental to reducing the potassium and sodium ion content and bringing the hydroxyl value closer to the theoretical hydroxyl value.

[0069] Example 9 Preparation of H-type ZSM-5 molecular sieve catalysts First, 8g of sodium-type ZSM-5 molecular sieve was acid-washed with a 7.5% (nitric acid) aqueous solution at a temperature of 80℃ for 2 hours. The volume of the acidic aqueous solution was 80mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 10:1. After acid washing, the sieve was repeatedly washed with deionized water until neutral. After washing, the sieve was dried at 120℃ for 4 hours to remove moisture and obtain the H-type ZSM-5 molecular sieve catalyst.

[0070] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.42g of sodium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 440g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0071] Add 7.4g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 100℃, and then add 464g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes, and obtain crude 1,4-butynediol block polyether.

[0072] The crude polyether was cooled to 60°C, 60g of deionized water was added, and the mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0073] The finished product of Example 9 was tested, and the results were: hydroxyl value 386.5 mg KOH / g, and potassium and sodium ion content 7.6 ppm.

[0074] Example 10 Preparation of H-type ZSM-5 molecular sieve catalysts First, 6g of sodium-type ZSM-5 molecular sieve was acid-washed with an 8% sulfuric acid aqueous solution at a temperature of 80℃ for 2 hours. The volume of the sulfuric acid aqueous solution was 90mL, meaning the ratio of the volume (mL) of the acidic aqueous solution to the mass (g) of the sodium-type ZSM-5 molecular sieve was 15:1. After acid washing, the solution was repeatedly washed with deionized water until neutral. After washing, the solution was dried at 120℃ for 4 hours to remove moisture and obtain the H-type ZSM-5 molecular sieve catalyst.

[0075] Specific applications of H-type ZSM-5 molecular sieve catalysts 86g of molten 1,4-butynediol was added to a reaction vessel, followed by 0.25g of potassium hydroxide. After the addition was complete, the air inside the vessel was replaced twice with nitrogen. Stirring was then started to ensure thorough mixing of the materials. The temperature was raised to 70°C, and 264g of ethylene oxide was slowly added dropwise. After the addition was complete, the reaction was continued until the pressure no longer changed, thus obtaining the 1,4-butynediol polyethoxy ether intermediate.

[0076] Add 5.6g of H-type ZSM-5 molecular sieve catalyst to the intermediate, heat to 75℃, and then add 580g of propylene oxide dropwise. After the addition is complete, continue the ripening reaction until the pressure no longer changes, and obtain crude 1,4-butynediol block polyether.

[0077] The crude polyether was cooled to 60°C, and 83g of deionized water was added. The mixture was stirred for 60 minutes. The molecular sieve catalyst was first filtered out (collected and reused), and then the water in the crude product was removed to obtain the 1,4-butynediol block polyether product.

[0078] The finished product of Example 10 was tested, and the results were: hydroxyl value 384.2 mg KOH / g, potassium and sodium ion content 4.8 ppm.

[0079] In this application, the hydroxyl value was determined according to the phthalic anhydride method specified in GB / T 7383-2007. The potassium and sodium ion contents were determined using a PerkinElmer_NexlON 350S inductively coupled plasma mass spectrometer.

[0080] The materials used in this application are conventional materials that are readily available for purchase.

[0081] The above embodiments are merely preferred embodiments of the present invention and should not be construed as limiting the scope of protection of the present invention. Any non-substantial changes and substitutions made by those skilled in the art based on the present invention shall fall within the scope of protection claimed by the present invention.

Claims

1. A method for preparing an H-form ZSM-5 molecular sieve catalyst, characterized in that, The method comprises the following steps: The sodium type ZSM-5 molecular sieve is subjected to acid pickling with an acidic aqueous solution, the acid pickling temperature is 80°C, the acid pickling time is 2 hours, the mass fraction of acid in the acidic aqueous solution is 5%-10%, and the volume (mL) of the acidic aqueous solution is 5-20 times the mass (g) of the sodium type ZSM-5 molecular sieve; After the acid pickling, the sodium type ZSM-5 molecular sieve is repeatedly washed with deionized water until neutral; After the washing, the sodium type ZSM-5 molecular sieve is dried at 120°C for 4 hours to obtain the H type ZSM-5 molecular sieve catalyst.

2. The production method according to claim 1, wherein The acid in the acidic aqueous solution is at least one of phosphoric acid, nitric acid and sulfuric acid.

3. The production method according to claim 2, wherein The mass fraction of acid in the acidic aqueous solution is 5%-7.5%, and the acid in the acidic aqueous solution is phosphoric acid.

4. The production method according to claim 3, wherein The volume (mL) of the acidic aqueous solution is 5-15 times the mass (g) of the sodium type ZSM-5 molecular sieve.

5. Use of the H-form ZSM-5 molecular sieve catalyst prepared by the preparation method according to any one of claims 1 to 4, characterized in that, The H type ZSM-5 molecular sieve catalyst is used to catalyze the ring-opening polymerization of an intermediate after an alcohol initiator and an epoxide are subjected to ring-opening polymerization under the catalysis of a basic catalyst to obtain the intermediate, and the H type ZSM-5 molecular sieve catalyst is also used to adsorb the basic catalyst to reduce the residual metal ions in the polyether product.