A silicon-zirconium super solid acid catalyst for synthesizing ethylene glycol by one-step method of synthesis gas, a preparation method and application thereof

Abstract

The application discloses a silicon-zirconium super strong solid acid catalyst for synthesizing ethylene glycol by one-step method of synthesis gas, a preparation method and application, and belongs to the technical field of catalytic chemistry. The preparation method comprises the following steps: placing a mixed solution containing a zirconium source, a template agent I and ethanol in a closed container, pre-crystallizing, and obtaining a zirconium source gel; slowly adding a mixed solution containing a silicon source, a template agent II, acid and water to the zirconium source gel under stirring, obtaining a mixed gel, placing the mixed gel in a closed container, hydrothermally crystallizing, washing and drying the hydrothermally crystallized product, and then roasting to obtain a silicon-zirconium super strong solid acid catalyst, and further metal modification can be continuously carried out. The catalyst prepared in the application can realize one-step continuous preparation of ethylene glycol by using water, hydrogen and carbon monoxide as raw materials in a fixed bed reactor.

Description

Technical Field

[0001] This application relates to a silicon-zirconium super-strong solid acid catalyst for one-step synthesis of ethylene glycol from syngas, its preparation method and application, belonging to the field of catalytic chemistry technology. Background Technology

[0002] Ethylene glycol, as an important chemical raw material, is widely used in polyester fibers, antifreeze, and other fields. Currently, its industrial production routes are mainly divided into petroleum-based and non-petroleum-based routes. The petroleum-based route uses ethylene as a raw material, which is produced through the hydration of ethylene oxide. This technology is mature but constrained by the volatility of petroleum resources. Among non-petroleum-based routes, the technology of producing ethylene glycol from syngas derived from coal or natural gas has attracted much attention, especially the oxalate hydrogenation process developed domestically, which has become the mainstream coal-to-ethylene glycol technology. However, this process involves multiple steps, including carbon monoxide coupling, esterification, and hydrogenation, resulting in a long process and typically relying on precious metal (such as palladium) catalysts, leading to high costs. Therefore, developing a short-process, high-efficiency catalytic technology for the direct one-step synthesis of ethylene glycol from syngas is of significant strategic and economic importance.

[0003] In terms of catalytic systems, the key to achieving one-step synthesis of oxygen-containing compounds (such as alcohols and acids) from syngas lies in designing bifunctional catalysts that simultaneously activate syngas and promote controllable carbon chain growth while introducing oxygen-containing functional groups. Solid acid catalysts play a central role in heterogeneous catalysis due to their ease of separation, reusability, and environmental friendliness. Common solid acids include molecular sieves (such as HZSM-5), heteropoly acids, and supported metal oxides (such as SO4). 2- Zirconium (ZrO2) and its composite oxides (such as SiO2-Al2O3) are also important catalyst supports. Among these, solid acids based on zirconium (Zr), particularly zirconium oxide sulfate, have been extensively studied due to their superacid properties, but they suffer from low specific surface area, insufficient thermal stability, and easy loss of active components during reactions. Introducing silicon (Si) to form silicon-zirconium composite oxides can effectively control the specific surface area, pore structure, and surface acidity of the material, enhancing its hydrothermal stability and mechanical strength, thus providing a possibility for constructing high-performance catalyst supports.

[0004] However, while solid silicon-zirconium acids can provide acidic sites, their catalytic ability for the one-step, highly selective, and directional conversion of syngas to ethylene glycol is generally limited. Studies have shown that modification with specific transition metals (such as Cu, Sn, and Co) can effectively activate hydrogen and carbon monoxide, and may, by constructing metal-acid co-catalytic centers, regulate the reaction pathway and suppress side reactions (such as methanation and the formation of higher hydrocarbons), thereby directing the reaction towards the target product, ethylene glycol. Currently, there are no mature reports on combining silicon-zirconium materials with specific pore structures and strong acidity with finely regulated transition metal active centers for the direct and efficient synthesis of ethylene glycol from the simplest components (water, hydrogen, and carbon monoxide). Summary of the Invention

[0005] To address the challenge of directly synthesizing ethylene glycol using simple components (water, hydrogen, and carbon monoxide) as raw materials in existing technologies, this application provides a silicon-zirconium super-strong solid acid catalyst solution for one-step synthesis of ethylene glycol from syngas. This solution enables continuous one-step production of ethylene glycol from water, hydrogen, and carbon monoxide in a fixed-bed reactor. The resulting ethylene glycol product exhibits high selectivity and is easily separated.

[0006] The technical solution adopted in this application is as follows: According to a first aspect of this application, a method for preparing a silicon-zirconium super-strong solid acid catalyst for one-step synthesis of ethylene glycol from syngas includes: A mixed solution containing zirconium source, template agent I, and ethanol was placed in a sealed container and pre-crystallized to obtain zirconium source gel. Under stirring conditions, a mixed solution containing silicon source, template agent II, acid and water is slowly added to the zirconium source gel to obtain a mixed gel. The mixed gel is placed in a sealed container for hydrothermal crystallization. The product of hydrothermal crystallization is washed with water, dried and then calcined to obtain a silicon-zirconium super solid acid catalyst.

[0007] Optionally, the molar ratio of each component in the mixed solution containing zirconium source, template agent I, and ethanol is: Zirconium source: Template agent I: Ethanol 1:0.5~50:10~1500; The amount of zirconium source used is calculated based on the number of moles of zirconium it contains; The amount of template agent used is calculated based on its own molar number; The amount of ethanol used is calculated based on its own mole count; Optionally, the zirconium source is selected from at least one of zirconium oxychloride octahydrate, zirconium citrate, zirconium nitrate, zirconium sulfate, and zirconium n-propoxide.

[0008] Optionally, the template agent I is selected from at least one of hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, tetrapropylammonium bromide, tetraethylammonium bromide, tetramethylammonium bromide, hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, tetrapropylammonium chloride, tetraethylammonium chloride, tetramethylammonium chloride, hexadecyltrimethylammonium hydroxide, dodecyltrimethylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, triethylamine, isopropylamine, diisopropylamine, triisopropylamine, n-butylamine, cyclohexylamine, caprolactam, hexamethyleneimine, heptamethyleneimine, cycloheptaneamine, and cyclopentaneamine.

[0009] Optionally, the molar ratio of each component in the zirconium source and the mixed solution containing the silicon source, template agent II, acid, and water is as follows: Zirconium source: Silicon source: Template agent II: Acid: Water = 1:1~100:1~100:1~50:10~500; The amount of zirconium source used is calculated based on the number of moles of zirconium it contains; The amount of silicon source used is calculated based on the number of moles of zirconium it contains; The amount of template agent used is calculated based on its own molar number; The amount of acid used is calculated based on its own molar quantity; Water consumption is calculated based on its own mole count; Optionally, the silicon source is selected from at least one of tetraethyl orthosilicate, silica sol, sodium silicate, and water glass.

[0010] Optionally, the template agent II is selected from at least one of hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, tetrapropylammonium bromide, tetraethylammonium bromide, tetramethylammonium bromide, hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, tetrapropylammonium chloride, tetraethylammonium chloride, tetramethylammonium chloride, hexadecyltrimethylammonium hydroxide, dodecyltrimethylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, triethylamine, isopropylamine, diisopropylamine, triisopropylamine, n-butylamine, cyclohexylamine, caprolactam, hexamethyleneimine, heptamethyleneimine, cycloheptaneamine, and cyclopentaneamine.

[0011] Optionally, the acid is selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, and acetic acid.

[0012] Optionally, the pre-crystallization conditions are: temperature of 100~190 °C and time of 2~48 h.

[0013] Optionally, after slowly adding a mixed solution containing a silicon source, template agent II, acid, and water to the zirconium source gel, the mixed solution is stirred at 30-50°C for 2-6 hours.

[0014] Optionally, the hydrothermal crystallization conditions are: a temperature of 100~190°C and a time of 8~48 h.

[0015] Optionally, the calcination conditions include a temperature of 400-600°C and a time of 2-8 hours.

[0016] Optionally, after washing and drying the hydrothermally crystallized product and then calcining it, the process further includes: The calcined product is placed in an impregnation solution containing metal salts for impregnation. A complexing agent is added to the impregnation solution until the pH value of the impregnation solution is 7-8. The product is then filtered, dried, and calcined to obtain the silicon-zirconium super solid acid catalyst.

[0017] Optionally, the metal salt is selected from at least one of copper nitrate, copper chloride, zinc nitrate, tin dichloride, ferric chloride, cobalt nitrate, and platinum nitrate.

[0018] Optionally, the complexing agent is selected from at least one of ammonium carbonate, sodium carbonate, sodium bicarbonate, and triethylamine.

[0019] Optionally, the impregnation conditions include: an impregnation temperature of 40~100 °C; and an impregnation time of 0.5~4 h.

[0020] Optionally, the calcination conditions are: a temperature of 400~600°C and a time of 2~8h.

[0021] According to a second aspect of this application, a silicon-zirconium super solid acid catalyst prepared by the above preparation method for one-step synthesis of ethylene glycol from syngas is provided, wherein the amount of metal modification in the silicon-zirconium super solid acid catalyst is 0-15%.

[0022] According to a third aspect of this application, a silicon-zirconium super-strong solid acid catalyst prepared by the above-described preparation method for the one-step synthesis of ethylene glycol from syngas, or the application of the above-described silicon-zirconium super-strong solid acid catalyst for the one-step synthesis of ethylene glycol from syngas, is characterized in that it comprises: Ethylene glycol is obtained by reacting raw materials containing water, hydrogen, and carbon monoxide with a silicon-zirconium super-strong solid acid catalyst.

[0023] Optionally, the molar ratio of hydrogen to water in the raw material is 10~30:1; The molar ratio of carbon monoxide to water in the raw material is 1~15:1; preferably 2~6.

[0024] Optionally, the reaction conditions include: a temperature of 150–300 °C, a reaction pressure of 0.5–6.0 MPa, and a total space velocity of 3–10 h⁻¹. -1 .

[0025] The beneficial effects of this application include: (1) The catalyst prepared by the technical solution of this application can realize the direct one-step synthesis of ethylene glycol from syngas and water in the one-step process, showing excellent catalytic performance. It can simultaneously achieve a high carbon monoxide conversion rate (>36%) and an extremely high ethylene glycol selectivity (>94%), with few by-products and a high yield of the target product.

[0026] (2) The technical route of this application simplifies the traditional multi-step process into a single-step reaction, which greatly shortens the process flow and is expected to reduce equipment investment and energy consumption, thus having significant advantages in process simplification. The raw materials used are only water, hydrogen and carbon monoxide, which are widely available and relatively inexpensive, making them particularly suitable for the conversion and utilization of carbon-rich resources (such as coal, natural gas and biomass), and of great strategic significance. Detailed Implementation

[0027] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0028] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0029] Unless otherwise specified, all test methods are standard and all instrument settings are those recommended by the manufacturer.

[0030] The testing conditions for this application are as follows: The composition of the products was qualitatively analyzed using an AVANCE III 500 NMR spectrometer manufactured by Bruker GmbH, Germany. Test conditions: detection temperature 25 °C, deuterated reagent: deuterated water, test mode: 1H NMR.

[0031] The product composition was quantitatively analyzed using the area normalization method with an Agilent 8860A gas chromatograph manufactured by Agilent Technologies, Inc. Test conditions: detection temperature 270 °C, vaporization temperature 250 °C; HP-5 capillary column (0.25 mm × 50 m); column temperature was controlled by a programmed temperature ramp method, holding at 60 °C for 3 min, then ramping to 200 °C at a rate of 7 °C / min and holding for 5 min.

[0032] In the embodiments of this application, the carbon monoxide conversion rate and the selectivity of the diol compound are calculated based on molar numbers: Carbon monoxide conversion rate % = (number of carbon moles of carbon monoxide in feed gas – number of carbon moles of ethylene glycol compounds in product) / number of carbon moles of carbon monoxide in feed gas × 100% (calculated based on the number of carbon moles). Ethylene glycol compound selectivity % = (number of carbon moles of ethylene glycol compound in the product) / (number of carbon moles of carbon monoxide in the feed gas – number of carbon moles of ethylene glycol compound in the product) × 100% (calculated based on the number of carbon moles).

[0033] According to one embodiment of this application, a method for preparing a silicon-zirconium superstrong solid acid catalyst for one-step synthesis of ethylene glycol from syngas includes: S1. Place the mixed solution containing zirconium source, template agent I, and ethanol in a sealed container and pre-crystallize it to obtain zirconium source gel. S2. Under stirring conditions, a mixed solution containing silicon source, template agent II, acid and water is slowly added to the zirconium source gel to obtain a mixed gel. The mixed gel is placed in a sealed container for hydrothermal crystallization. The hydrothermally crystallized product is washed with water, dried and then calcined.

[0034] S3. The calcined product is placed in an impregnation solution containing metal salts for impregnation. A complexing agent is added to the impregnation solution until the pH value of the impregnation solution is 7-8. The product is then filtered, dried, and calcined to obtain the silicon-zirconium super solid acid catalyst.

[0035] In one embodiment, the molar ratio of each component in the mixed solution containing the zirconium source, template agent I, and ethanol is: Zirconium source: Template agent I: Ethanol = 1:0.5~50:10~1500; The amount of zirconium source used is calculated based on the number of moles of zirconium it contains; The amount of template agent used is calculated based on its own molar number; The amount of ethanol used is calculated based on its own molar number.

[0036] In one embodiment, the molar ratio of zirconium source to template agent I is selected from any value or a range between 1:0.5, 1:1, 1:2, 1:3, 1:4, 1:5, 1:10, 1:20, 1:30, 1:40, and 1:50.

[0037] In one embodiment, the molar ratio of zirconium source to ethanol is selected from any value or a range between 1:10, 1:100, 1:200, 1:300, 1:400, 1:500, 1:600, 1:700, 1:800, 1:900, 1:1000, 1:1100, 1:1200, 1:1300, 1:1400, and 1:1500.

[0038] In one embodiment, the zirconium source is selected from at least one of zirconium oxychloride octahydrate, zirconium citrate, zirconium nitrate, zirconium sulfate, and zirconium n-propoxide.

[0039] In one embodiment, the template agent I is selected from at least one of hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, tetrapropylammonium bromide, tetraethylammonium bromide, tetramethylammonium bromide, hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, tetrapropylammonium chloride, tetraethylammonium chloride, tetramethylammonium chloride, hexadecyltrimethylammonium hydroxide, dodecyltrimethylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, triethylamine, isopropylamine, diisopropylamine, triisopropylamine, n-butylamine, cyclohexylamine, caprolactam, hexamethyleneimine, heptamethyleneimine, cycloheptaneamine, and cyclopentaneamine.

[0040] In one embodiment, the molar ratio of each component in the zirconium source and the mixed solution containing the silicon source, template agent II, acid, and water is as follows: Zirconium source: Silicon source: Template agent II: Acid: Water = 1:1~100:1~100:1~50:10~500; The amount of zirconium source used is calculated based on the number of moles of zirconium it contains; The amount of silicon source used is calculated based on the number of moles of zirconium it contains; The amount of template agent used is calculated based on its own molar number; The amount of acid used is calculated based on its own molar quantity; Water consumption is calculated based on its own mole count.

[0041] In one embodiment, the molar ratio of the zirconium source to the silicon source is selected from any value or a range between 1:1, 1:2, 1:3, 1:4, 1:5, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, and 1:100.

[0042] In one embodiment, the molar ratio of zirconium source to template agent II is selected from any value or a range between 1:1, 1:2, 1:3, 1:4, 1:5, 1:10, 1:20, 1:30, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, and 1:100.

[0043] In one embodiment, the molar ratio of the zirconium source to the acid is selected from any value or a range between 1:1, 1:2, 1:3, 1:4, 1:5, 1:10, 1:15, 1:20, 1:25, 1:30, 1:35, 1:40, 1:45, and 1:50.

[0044] In one embodiment, the molar ratio of zirconium source to water is selected from any value or a range between 1:10, 1:50, 1:100, 1:150, 1:200, 1:350, 1:400, 1:450, and 1:500.

[0045] In one embodiment, the silicon source is selected from at least one of tetraethyl orthosilicate, silica sol, sodium silicate, and water glass.

[0046] In one embodiment, the template agent II is selected from at least one of hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, tetrapropylammonium bromide, tetraethylammonium bromide, tetramethylammonium bromide, hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, tetrapropylammonium chloride, tetraethylammonium chloride, tetramethylammonium chloride, hexadecyltrimethylammonium hydroxide, dodecyltrimethylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, triethylamine, isopropylamine, diisopropylamine, triisopropylamine, n-butylamine, cyclohexylamine, caprolactam, hexamethyleneimine, heptamethyleneimine, cycloheptaneamine, and cyclopentaneamine.

[0047] In one embodiment, the acid is selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, and acetic acid.

[0048] In one embodiment, the pre-crystallization conditions are: a temperature of 100~190 °C and a time of 2~48 h.

[0049] In one embodiment, a mixed solution containing a silicon source, template agent II, acid, and water is slowly added to the zirconium source gel, and the mixed solution is stirred at 30-50°C for 2-6 hours. The specific rate of slow addition is not strictly limited in this application; those skilled in the art can select the appropriate rate to implement the technical solution as needed.

[0050] In one embodiment, the hydrothermal crystallization conditions are: a temperature of 100~190°C and a time of 8~48h.

[0051] In one embodiment, the calcination conditions include a temperature of 400-600°C and a time of 2-8 hours.

[0052] In one embodiment, the metal salt is selected from at least one of copper nitrate, copper chloride, zinc nitrate, tin dichloride, ferric chloride, cobalt nitrate, and platinum nitrate.

[0053] In one embodiment, the complexing agent is selected from at least one of ammonium carbonate, sodium carbonate, sodium bicarbonate, and triethylamine.

[0054] In one embodiment, the immersion conditions include: an immersion temperature of 40~100 °C; and an immersion time of 0.5~4 h.

[0055] In one embodiment, the calcination conditions are: a temperature of 400~600°C and a time of 2~8 hours.

[0056] According to one embodiment of this application, the silicon-zirconium super solid acid catalyst prepared by the above preparation method for one-step synthesis of ethylene glycol from syngas has a metal modification amount of 0~15%.

[0057] In one embodiment, the amount of metal modification in the silicon-zirconium super solid acid catalyst is selected from any value or a range between 0.01%, 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, and 15%, preferably 8 to 12%.

[0058] In this application, the amount of metal modification in the catalyst refers to the mass content of the metal in the catalyst, calculated as a metal element.

[0059] According to one embodiment of this application, the silicon-zirconium super-strong solid acid catalyst for one-step synthesis of ethylene glycol from syngas prepared by the above-described preparation method, or the above-described silicon-zirconium super-strong solid acid catalyst for one-step synthesis of ethylene glycol from syngas, is used for one-step synthesis of ethylene glycol from syngas, comprising: Ethylene glycol is obtained by reacting raw materials containing water, hydrogen, and carbon monoxide with a silicon-zirconium super-strong solid acid catalyst.

[0060] In one embodiment, the molar ratio of hydrogen to water in the raw material is 10~30:1; The molar ratio of carbon monoxide to water in the raw material is 1~15:1; preferably 2~6.

[0061] In one embodiment, the reaction conditions include: a temperature of 150–300 °C, a reaction pressure of 0.5–6.0 MPa, and a total space velocity of 3–10 h⁻¹. -1 .

[0062] In one embodiment, the reaction temperature is preferably 210-250°C, and more preferably 215-225°C.

[0063] In one embodiment, the reaction pressure is preferably 3 to 4.5 MPa.

[0064] In one embodiment, the catalyst is further activated before the raw material containing water, hydrogen and carbon monoxide is brought into contact with the silicon zirconium super solid acid catalyst. The activation step includes: subjecting the silicon-zirconium super solid acid catalyst to a reducing gas purging and a carrier gas purging at an activation temperature.

[0065] In one embodiment, the reducing gas is selected from at least one of hydrogen, carbon monoxide, and pyridine; The carrier gas is selected from at least one of nitrogen, helium, and argon; In one embodiment, the reducing gas is hydrogen and / or carbon monoxide.

[0066] In one embodiment, the activation temperature is 100~400 °C, preferably 150~250 °C.

[0067] In one embodiment, the activation time is 2 to 48 hours, preferably 10 to 14 hours.

[0068] In one embodiment, the carrier gas purging time is 1 to 4 hours.

[0069] In one embodiment, the apparatus used for the reaction is a fixed-bed reactor or a batch reactor.

[0070] Examples 1-21 A super-strong silicon-zirconium solid acid was synthesized and metal-modified using a two-step hydrothermal method, as follows: (1) Dissolve the zirconium source in 100 mL of ethanol to prepare a zirconium source ethanol solution with a zirconium ion concentration of 0.03 mol / L; then dissolve 2.1 g of hexadecyltrimethylammonium bromide in 100 mL of ethanol. Next, mix the prepared zirconium source ethanol solution and the hexadecyltrimethylammonium bromide ethanol solution, transfer them to a hydrothermal reactor, and perform hydrothermal treatment at 110 °C for 4 hours to obtain zirconium source gel. (2) The silicon source was slowly added to 20 mL of dilute acid solution, and 1 g of P123 was slowly added under low-speed stirring. The mixture was then stirred at 40 °C for 3 hours. After the hydrothermal treatment of the solution in the previous step was completed, the zirconium source gel was taken out and mixed with the above solution, and stirred at room temperature for 3 hours. Then it was transferred to a hydrothermal reactor again and hydrothermally treated at 100 °C for 48 hours. After the hydrothermal reaction was completed, it was cooled to room temperature, filtered and washed with a large amount of water, dried at room temperature, and calcined at 600 °C for 6 hours to remove the template agent, thus obtaining the silicon-zirconium super-strong solid acid catalyst.

[0071] If metallic finishing is included, the following steps are also included: (3) Take 5 g of the calcined product from step (2) and put it into an impregnation solution consisting of a metal salt (the amount of which is based on the amount of metal modification in the catalyst) and 100 mL of water. Stir at 60°C for 24 hours, then add a complexing agent in batches. After the pH of the solution is 7-8, cool it to room temperature, filter and wash it, dry it at 90°C overnight, and calcine it at 550°C for 6 hours to obtain a silicon zirconium super strong solid acid catalyst. The selection of different raw materials and the amounts of silicon source, zirconium source, acid, and metal salt in the steps are shown in Table 1. The amount of silicon source is calculated based on the number of moles of silicon it contains, the amount of zirconium source is calculated based on the number of zirconium elements it contains as 0.03 mol, and the amount of metal salt is calculated based on the amount of metal modification.

[0072] Table 1

[0073] Test case The silicon-zirconium super-strong solid acid catalysts prepared in Examples 1 to 21 were used to test the one-step continuous production of ethylene glycol in a fixed-bed reactor using water, hydrogen, and carbon monoxide as raw materials. (1) Catalyst activation: 1 g of catalyst is packed into a fixed bed reactor, and carbon monoxide is introduced at an activation temperature of 190 °C for 12 hours. Then, nitrogen is purged at the same temperature for 2 hours to complete the activation of the catalyst. (2) Ethylene glycol synthesis: under reaction conditions, carbon monoxide, hydrogen and water are introduced into a fixed bed reactor (carbon monoxide is directly introduced as a gas sample, and water is introduced after heating and vaporization) to react with the activated catalyst. The tail gas is analyzed by gas chromatography online, the conversion rate of carbon monoxide and the selectivity of glycol compounds are calculated, and the condensate is collected. The product type is determined by nuclear magnetic resonance hydrogen spectroscopy. Raw materials and dosage: The raw materials are carbon monoxide, hydrogen and water in a molar ratio of 10:20:1, and the total space velocity of the raw materials is 10 h⁻¹. -1 ; Reaction conditions: The reaction temperature and reaction pressure are shown in Table 2.

[0074] The test results for carbon monoxide conversion and ethylene glycol selectivity are shown in Table 2.

[0075] Table 2

[0076] In summary, the data in the table shows that the proven conclusions for a silicon-zirconium super-strong solid acid catalyst used in the one-step synthesis of ethylene glycol from syngas include: (1) The silicon-zirconium super-strong solid acid catalyst prepared by this method can convert water, carbon monoxide and hydrogen into ethylene glycol with higher value under relatively mild reaction conditions of 190~210℃ and 4.0MPa, and can achieve a carbon monoxide conversion rate of more than 30% and an ethylene glycol selectivity of more than 79%.

[0077] (2) For the silicon-zirconium super solid acid catalyst prepared by this method, the ratio of silicon source to zirconium source during the preparation process will affect the catalytic efficiency of the catalyst. The higher the silicon-zirconium ratio, the lower the carbon monoxide conversion rate exhibited by the catalyst.

[0078] (3) By modifying the prepared silicon zirconium super solid acid catalyst with metal, the selectivity of ethylene glycol and the conversion rate of carbon monoxide can be effectively improved. Among various doped metals, the silicon zirconium super solid acid catalyst doped with tin metal exhibits the highest ethylene glycol selectivity and carbon monoxide conversion rate.

[0079] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for preparing a silicon-zirconium superstrong solid acid catalyst for one-step synthesis of ethylene glycol from syngas, characterized in that, include: A mixed solution containing zirconium source, template agent I, and ethanol was placed in a sealed container and pre-crystallized to obtain zirconium source gel. Under stirring conditions, a mixed solution containing silicon source, template agent II, acid and water is slowly added to the zirconium source gel to obtain a mixed gel. The mixed gel is placed in a sealed container for hydrothermal crystallization. The product of hydrothermal crystallization is washed with water, dried and then calcined to obtain a silicon-zirconium super solid acid catalyst.

2. The preparation method according to claim 1, characterized in that, The molar ratio of each component in the mixed solution containing zirconium source, template agent I, and ethanol is as follows: Zirconium source: Template agent I: Ethanol = 1:0.5~50:10~1500; The amount of zirconium source used is calculated based on the number of moles of zirconium it contains; The amount of template agent used is calculated based on its own molar number; The amount of ethanol used is calculated based on its own mole count; Preferably, the zirconium source is selected from at least one of zirconium oxychloride octahydrate, zirconium citrate, zirconium nitrate, zirconium sulfate, and zirconium n-propoxide; Preferably, the template agent I is selected from at least one of hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, tetrapropylammonium bromide, tetraethylammonium bromide, tetramethylammonium bromide, hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, tetrapropylammonium chloride, tetraethylammonium chloride, tetramethylammonium chloride, hexadecyltrimethylammonium hydroxide, dodecyltrimethylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, triethylamine, isopropylamine, diisopropylamine, triisopropylamine, n-butylamine, cyclohexylamine, caprolactam, hexamethyleneimine, heptamethyleneimine, cycloheptaneamine, and cyclopentaneamine.

3. The preparation method according to claim 1, characterized in that, The molar ratios of the components in the zirconium source and the mixed solution containing the silicon source, template agent II, acid, and water are as follows: Zirconium source: Silicon source: Template agent II: Acid: Water = 1:1~100:1~100:1~50:10~500; The amount of zirconium source used is calculated based on the number of moles of zirconium it contains; The amount of silicon source used is calculated based on the number of moles of zirconium it contains; The amount of template agent used is calculated based on its own molar number; The amount of acid used is calculated based on its own molar quantity; Water consumption is calculated based on its own mole count; Preferably, the silicon source is selected from at least one of tetraethyl orthosilicate, silica sol, sodium silicate, and water glass; Preferably, the template agent II is selected from at least one of hexadecyltrimethylammonium bromide, dodecyltrimethylammonium bromide, tetrapropylammonium bromide, tetraethylammonium bromide, tetramethylammonium bromide, hexadecyltrimethylammonium chloride, dodecyltrimethylammonium chloride, tetrapropylammonium chloride, tetraethylammonium chloride, tetramethylammonium chloride, hexadecyltrimethylammonium hydroxide, dodecyltrimethylammonium hydroxide, tetrapropylammonium hydroxide, tetraethylammonium hydroxide, tetramethylammonium hydroxide, triethylamine, isopropylamine, diisopropylamine, triisopropylamine, n-butylamine, cyclohexylamine, caprolactam, hexamethyleneimine, heptamethylimine, cycloheptaneamine, and cyclopentaneamine. Preferably, the acid is selected from at least one of sulfuric acid, hydrochloric acid, nitric acid, and acetic acid.

4. The preparation method according to claim 1, characterized in that, The pre-crystallization conditions are: temperature 100~190°C, time 2~48 h.

5. The preparation method according to claim 1, characterized in that, After slowly adding a mixed solution containing silicon source, template agent II, acid and water to the zirconium source gel, the mixed solution is stirred at 30~50°C for 2~6 h.

6. The preparation method according to claim 1, characterized in that, The conditions for hydrothermal crystallization are: temperature 100~190°C, time 8~48 h; Preferably, the calcination conditions include a temperature of 400~600°C and a time of 2~8h.

7. The preparation method according to claim 1, characterized in that, After washing and drying the hydrothermally crystallized product and then calcining it, the process further includes: The calcined product is placed in an impregnation solution containing metal salts for impregnation. A complexing agent is added to the impregnation solution until the pH value of the impregnation solution is 7-8. The product is then filtered, dried, and calcined to obtain the silicon-zirconium super solid acid catalyst. The metal salt is selected from at least one of copper nitrate, copper chloride, zinc nitrate, tin dichloride, ferric chloride, cobalt nitrate, and platinum nitrate. Preferably, the complexing agent is selected from at least one of ammonium carbonate, sodium carbonate, sodium bicarbonate, and triethylamine; Preferably, the impregnation conditions include: an impregnation temperature of 40~100 °C; and an impregnation time of 0.5~4 h; Preferably, the calcination conditions are: a temperature of 400~600°C and a time of 2~8h.

8. The silicon-zirconium superstrong solid acid catalyst for one-step synthesis of ethylene glycol from syngas, prepared by the method according to any one of claims 1 to 7, is characterized in that... The amount of metal modification in the silicon-zirconium super solid acid catalyst is 0~15wt%.

9. The application of the silicon-zirconium super-strong solid acid catalyst for one-step synthesis of ethylene glycol from syngas prepared by the preparation method according to any one of claims 1 to 7, or the silicon-zirconium super-strong solid acid catalyst for one-step synthesis of ethylene glycol from syngas according to claim 8, in the one-step synthesis of ethylene glycol from syngas, characterized in that, include: Ethylene glycol is obtained by reacting raw materials containing water, hydrogen, and carbon monoxide with a silicon-zirconium super-strong solid acid catalyst.

10. The application according to claim 9, characterized in that, The molar ratio of hydrogen to water in the raw material is 10~30:1; The molar ratio of carbon monoxide to water in the raw materials is 1~15:1; Preferably, the reaction conditions include: a temperature of 150–300 °C, a reaction pressure of 0.5–6.0 MPa, and a total space velocity of 3–10 h⁻¹. -1 .

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