Preparation method and application of a tin selenide mordenite catalyst

Abstract

This application discloses a method for preparing and applying a tin selenide-supported ferruginous zeolite catalyst, belonging to the field of catalytic chemistry. The preparation method includes: pre-crystallizing a mixed solution containing a silicon source, an aluminum source, a template agent, and water to obtain a silica-alumina gel; under stirring conditions, slowly adding a mixed solution containing a tin source, a selenium source, and ethanol sequentially, and then slowly adding an alkali to the silica-alumina gel to obtain a mixed gel; placing the mixed gel in a sealed container for hydrothermal crystallization; washing and drying the hydrothermally crystallized product, followed by calcination, to obtain the tin selenide-supported ferruginous zeolite catalyst. This application, by modifying silica-alumina molecular sieves with tin selenide, enables one-step ethanol production using hydrogen and carbon dioxide as raw materials in a fixed-bed reactor. Furthermore, the selectivity of ethanol can be adjusted by modifying the catalyst preparation process.

Description

Technical Field

[0001] This application relates to a method for preparing and applying a supported tin selenide ferruginous zeolite catalyst, belonging to the field of catalytic chemistry technology. Background Technology

[0002] In recent years, with the increasing prominence of global energy demand and environmental issues, the conversion of carbon dioxide into high-value-added chemicals and fuels has become a research hotspot in the field of catalysis. The hydrogenation of carbon dioxide to ethanol is a highly attractive technological route, as ethanol is not only a clean fuel but also an important chemical feedstock. However, this reaction process faces thermodynamic and kinetic challenges: carbon dioxide molecules are relatively stable and difficult to activate, and the hydrogenation process easily generates various byproducts such as methane, carbon monoxide, and methanol, leading to low ethanol selectivity. Currently, the catalyst systems reported in the literature are mainly divided into two categories: one is metal oxide or modified Fischer-Tropsch synthesis catalysts, whose ethanol selectivity generally does not exceed 30%; the other is metal or metal oxide catalysts based on molecular sieves, which, although able to modulate product distribution through the acidity or pore structure of the molecular sieve, still struggle to achieve high selective ethanol production.

[0003] Tin selenide, as a narrow bandgap semiconductor material, exhibits unique properties in photoelectrocatalysis and thermocatalysis, particularly demonstrating potential selectivity for C2+ oxygen-containing compounds in the catalytic hydrogenation of carbon dioxide. However, pure tin selenide materials have a small specific surface area, poor stability, and difficulty in suppressing side reactions, limiting their application in industrial catalysis. Mordenite molecular sieves, due to their unique pore structure, tunable acidity, and good thermal stability, are widely used as catalyst supports, but their activity is limited when used alone in the carbon dioxide hydrogenation reaction, and their selectivity for ethanol is not outstanding.

[0004] How to organically combine the high catalytic activity of tin selenide with the structural advantages of mordenite to design a catalyst that can efficiently and selectively convert carbon dioxide into ethanol has become a pressing technical problem in this field. Summary of the Invention

[0005] To address the issues of low ethanol selectivity and insufficient carbon dioxide conversion in existing carbon dioxide hydrogenation to ethanol technologies, this application provides a tin selenide mordenite zeolite catalyst technology for one-step ethanol production from carbon dioxide. By modifying a silica-alumina molecular sieve with tin selenide, ethanol can be continuously produced in a fixed-bed reactor using hydrogen and carbon dioxide as raw materials in a one-step process. Furthermore, the ethanol selectivity can be adjusted by modifying the catalyst preparation process.

[0006] The technical solution adopted in this application is as follows: According to a first aspect of this application, a method for preparing a supported tin selenide ferrite zeolite catalyst is provided, comprising: A mixed solution containing silicon source, aluminum source, template agent and water is pre-crystallized to obtain silicon-aluminum gel; Under stirring conditions, a mixed solution containing tin source, selenium source and ethanol was slowly added to the silica-alumina gel in sequence, followed by the slow addition of alkali to obtain a mixed gel. The mixed gel was placed in a sealed container and subjected to hydrothermal crystallization. The product of the hydrothermal crystallization was washed with water, dried, and then calcined to obtain the supported tin selenide ferruginous zeolite catalyst.

[0007] Optionally, the molar ratio of each component in the mixed solution containing silicon source, aluminum source, template agent, and water is: Silicon source: Aluminum source: Template agent: Water = 1~100:1:0.5~50:10~500; The amount of silicon source used is calculated based on the number of moles of silicon it contains; The amount of aluminum source used is calculated based on the number of moles of aluminum it contains; The amount of template agent used is calculated based on its own molar number; The amount of water used is calculated based on its own mole count.

[0008] Optionally, the silicon source is selected from at least one of tetraethyl orthosilicate, silica sol, sodium silicate, and water glass.

[0009] Optionally, the aluminum source is selected from at least one of aluminum sulfate, aluminum chloride, aluminum powder, aluminum isopropoxide, and aluminum hydroxide.

[0010] Optionally, the template agent 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 components in the mixed gel and their molar ratios to the aluminum source are as follows: Selenium source: Tin source: Alkali: Aluminum source = 1~5: 1~5: 0.1~0.5: 1; The amount of tin source used is calculated based on the number of moles of tin it contains; The amount of selenium source used is calculated based on the number of moles of selenium it contains; The amount of alkali used is calculated based on its own molar number; The amount of aluminum source used is calculated based on the number of moles of aluminum in it.

[0012] Optionally, the tin source is selected from at least one of tin nitrate, tin sulfate, and stannous chloride; Optionally, the selenium source is selected from at least one of selenium dioxide and potassium selenite; Optionally, the base is selected from at least one of triethylamine, ammonium carbonate, and diethylamine.

[0013] Optionally, the pre-crystallization conditions are: a temperature of 50~60°C and a time of 2~4h.

[0014] Optionally, after slowly adding a mixed solution containing a tin source, a selenium source and ethanol to the silica-alumina gel in sequence, stirring is maintained for 2 to 6 hours. Preferably, the stirring conditions include a stirring temperature of 50~70 °C.

[0015] Optionally, the hydrothermal crystallization conditions are: a temperature of 100~190°C and a time of 8~72h.

[0016] Optionally, the hydrothermal crystallization conditions are: reacting at 100~120°C for 8~24h, and then reacting at 120~190°C for 24~48h.

[0017] Optionally, the calcination conditions are: a temperature of 300~600°C and a time of 2~8h.

[0018] According to a second aspect of this application, a supported tin selenide ferroluminescent zeolite catalyst prepared by the aforementioned preparation method is provided, wherein the silicon-to-aluminum ratio is 5~100:1.

[0019] According to a third aspect of this application, an application is provided of the supported tin selenide filament zeolite catalyst prepared by the aforementioned preparation method or the aforementioned supported tin selenide filament zeolite catalyst in the production of ethanol from carbon dioxide, comprising: Ethanol is obtained by contacting raw materials containing hydrogen and carbon dioxide with a supported tin selenide ferruginous zeolite catalyst.

[0020] Optionally, the molar ratio of hydrogen to carbon dioxide in the raw material is 1 to 15:1.

[0021] 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 3–6 h⁻¹. -1 .

[0022] Optionally, the catalyst may be activated before the feedstock containing hydrogen and carbon dioxide is contacted with the supported tin selenide ferrite zeolite catalyst. The activation step includes: at the activation temperature, the supported tin selenide ferruginous zeolite catalyst is sequentially purged with a reducing gas and then purged with a carrier gas.

[0023] Optionally, the reducing gas is selected from at least one of hydrogen, carbon monoxide, and pyridine.

[0024] Optionally, the reducing gas is selected from hydrogen and / or carbon monoxide.

[0025] Optionally, the carrier gas is selected from at least one of nitrogen, helium, and argon.

[0026] Optionally, the activation temperature is 100~400 °C.

[0027] Optionally, the activation time is 2 to 48 hours.

[0028] Optionally, the activation temperature is 150~250 °C.

[0029] Optionally, the apparatus used for the reaction is a fixed-bed reactor or a batch reactor.

[0030] The beneficial effects of this application include: The technical solution of this application effectively combines the catalytic activity of tin selenide with the structure and acidic characteristics of mordenite by loading tin selenide onto mordenite molecular sieve, thereby giving full play to the synergistic effect of the two and achieving the following results: (1) High ethanol selectivity and excellent carbon dioxide conversion rate: The pore structure and acidic sites of mordenite can modulate the conversion pathway of reaction intermediates, inhibit the generation of by-products such as methane, and, in conjunction with the catalytic effect of tin selenide, promote the activation and hydrogenation of carbon dioxide, and significantly improve the selectivity of carbon dioxide hydrogenation to ethanol.

[0031] (2) Good industrial application prospects: The preparation method of this application can realize the one-step production of ethanol in a fixed bed reactor by modifying the silicon-aluminum molecular sieve with tin selenide. Furthermore, the selectivity of ethanol can be adjusted by adjusting the catalyst preparation process, thus having good industrial application prospects. Detailed Implementation

[0032] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0033] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0034] Unless otherwise specified, all test methods are standard and all instrument settings are those recommended by the manufacturer.

[0035] According to one embodiment of this application, a method for synthesizing a supported tin selenide ferrite zeolite catalyst includes: S1. A mixed solution containing silicon source, aluminum source, template agent and water is pre-crystallized to obtain silicon-aluminum gel; S2. Under stirring conditions, a mixed solution containing tin source, selenium source and ethanol is slowly added to the silica-alumina gel in sequence, followed by the slow addition of alkali to obtain a mixed gel. S3. The mixed gel is placed in a sealed container and subjected to hydrothermal crystallization. The product of hydrothermal crystallization is washed with water, dried, and then calcined to obtain the supported tin selenide ferruginous zeolite catalyst.

[0036] In one embodiment, the molar ratio of each component in the mixed solution containing silicon source, aluminum source, template agent, and water is: Silicon source: Aluminum source: Template agent: Water = 1~100:1:0.5~50:10~2000; The amount of silicon source used is calculated based on the number of moles of silicon; the amount of aluminum source used is calculated based on the number of moles of aluminum; the amount of template agent used is calculated based on its own number of moles; and the amount of water used is calculated based on its own number of moles.

[0037] In one embodiment, the molar ratio of silicon source to aluminum source is selected from any value or a range between 1:1, 10:1, 20:1, 30:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1, and 100:1.

[0038] In one embodiment, the molar ratio of silicon source to aluminum source is preferably 60 to 100:1.

[0039] In one embodiment, the molar ratio of the template agent to the aluminum source is selected from any value or a range between 0.5:1, 1:1, 5:1, 10:1, 15:1, 25:1, 30:1, 35:1, 40:1, 45:1, and 50:1.

[0040] In one embodiment, the molar ratio of water to aluminum source is selected from any value or a range between 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, 1400:1, 1500:1, 1600:1, 1700:1, 1800:1, 1900:1, and 2000:1.

[0041] In one embodiment, the silicon source is selected from at least one of tetraethyl orthosilicate, silica sol, sodium silicate, and water glass.

[0042] In one embodiment, the aluminum source is selected from at least one of aluminum sulfate, aluminum chloride, aluminum powder, aluminum isopropoxide, and aluminum hydroxide.

[0043] In one embodiment, the template agent 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.

[0044] In one embodiment, the components of the mixed gel and their molar ratios to the aluminum source are as follows: Selenium source: Tin source: Alkali: Aluminum source = 1~5: 1~5: 0.1~0.5: 1; The amount of tin and selenium source used is calculated based on the number of moles of selenium and tin they contain; the amount of aluminum source used is calculated based on the number of moles of aluminum; and the amount of alkali used is calculated based on its own number of moles.

[0045] In one embodiment, the molar ratio of the selenium source to the aluminum source is selected from any value of 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1, or any range between the two.

[0046] In one embodiment, the molar ratio of tin source to selenium source is 1:2 to 2:1.

[0047] In one embodiment, the molar ratio of tin source to aluminum source is selected from any value of 1:1, 1.5:1, 2:1, 2.5:1, 3:1, 3.5:1, 4:1, 4.5:1, 5:1 or any range between the two.

[0048] In one embodiment, the molar ratio of alkali to aluminum source is selected from any value or a range between 0.1:1, 0.15:1, 0.2:1, 0.25:1, 0.3:1, 0.35:1, 0.4:1, 0.45:1, and 0.5:1.

[0049] In one embodiment, the tin source is selected from at least one of tin nitrate, tin sulfate, and stannous chloride.

[0050] In one embodiment, the selenium source is selected from at least one of selenium dioxide and potassium selenite.

[0051] In one embodiment, the alkali is selected from at least one of triethylamine, ammonium carbonate, and diethylamine, preferably triethylamine or ammonium carbonate.

[0052] In one embodiment, the pre-crystallization conditions are: a temperature of 50-60°C and a time of 2-4 hours.

[0053] In one embodiment, a mixed solution containing a tin source, a selenium source, and ethanol is slowly added to the silica-alumina gel in sequence, and then stirred for 2 to 6 hours.

[0054] In one embodiment, the alkali is slowly added under stirring conditions and then stirring is maintained for 0 to 1 hour.

[0055] In one embodiment, the slow addition method described in this application is drip addition, and the dripping speed is not strictly limited. Those skilled in the art can adjust it as needed to implement the technical solution of this application.

[0056] In one embodiment, the stirring conditions include a stirring temperature of 50~70°C.

[0057] In one embodiment, the hydrothermal crystallization conditions are: a temperature of 100~190°C and a time of 8~72h.

[0058] In one embodiment, the hydrothermal crystallization conditions are: reacting at 80~170 °C for 8~48 h, and then reacting at 80~190 °C for 8~48 h.

[0059] In one embodiment, the hydrothermal crystallization conditions are preferably: the hydrothermal crystallization conditions are: reacting at 90~110°C for 24~48h, and then reacting at 110~130°C for 18~24h.

[0060] In one embodiment, the calcination conditions are: a temperature of 300~600°C and a time of 2~8 hours.

[0061] In one embodiment, the preferred calcination conditions are: a temperature of 450-550°C and a time of 6-8 hours.

[0062] According to one embodiment of this application, the silicon-to-aluminum ratio of the supported tin selenide ferruginous zeolite catalyst obtained by the aforementioned synthesis method is 5~100:1.

[0063] In one embodiment, the silicon-to-aluminum ratio of the supported tin selenide ferrite zeolite catalyst is selected from any value or a range between 5:1, 10:1, 20:1, 30:1, 40:1, 50:1, 60:1, 70:1, 80:1, 90:1, and 100:1.

[0064] In one embodiment, the silicon-to-aluminum ratio of the supported tin selenide ferruginous zeolite catalyst is preferably 60 to 100:1.

[0065] According to another embodiment of this application, the supported tin selenide ferrolithium catalyst obtained by the aforementioned preparation method is applied to the production of ethanol from carbon dioxide, comprising: contacting a raw material containing hydrogen and carbon dioxide with the catalyst, reacting, and obtaining ethanol.

[0066] In one embodiment, the molar ratio of hydrogen to carbon dioxide in the raw materials is 1 to 15:1, preferably 2 to 6:1.

[0067] 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 3–6 h⁻¹. -1 .

[0068] In one embodiment, the catalyst is further activated before the feedstock containing hydrogen and carbon dioxide is contacted with the supported tin selenide ferrite zeolite catalyst. The activation step includes: at the activation temperature, the supported tin selenide ferruginous zeolite catalyst is sequentially purged with a reducing gas and then purged with a carrier gas.

[0069] In one embodiment, the reducing gas is selected from at least one of hydrogen, carbon monoxide, and pyridine.

[0070] In one embodiment, the reducing gas is selected from hydrogen and / or carbon monoxide.

[0071] In one embodiment, the carrier gas is selected from at least one of nitrogen, helium, and argon.

[0072] In one embodiment, the activation temperature is 100~400 °C.

[0073] In one embodiment, the activation time is 2 to 48 hours.

[0074] In one embodiment, the activation temperature is preferably 150~250 °C.

[0075] In one embodiment, the apparatus used for the reaction is a fixed-bed reactor or a batch reactor.

[0076] Examples 1-17 The preparation steps of Examples 1-17 are as follows: Silicon source and aluminum source are thoroughly mixed. Template agent is weighed and dissolved in 20 mL of deionized water, and slowly added dropwise to the previously mixed solution while stirring. After complete addition, the mixture is stirred continuously at 60 °C for 2 hours. Subsequently, a mixed solution consisting of tin source, selenium source, and 100 mL of ethanol is slowly added dropwise to the above solution, and stirred continuously at 60 °C for 4 hours. Then, alkali is slowly added and stirring is continued for 30 minutes. After stirring is complete, the resulting gel is transferred to a 100 mL reaction vessel lined with tetrafluoroethylene. The first and second stages of hydrothermal reactions are carried out sequentially. After the reaction is complete, the mixture is naturally cooled to room temperature, filtered, washed with water, dried at 120 °C overnight, and calcined in a muffle furnace to obtain tin selenide-supported mordenite molecular sieve.

[0077] The molar amounts of silicon source, aluminum source, template agent, tin source, selenium source, and alkali are shown in Table 1. The amount of aluminum source is 0.6 mmol based on the amount of aluminum it contains, the amount of silicon source is calculated based on the number of moles of silicon it contains, the amount of template agent is calculated based on its own molar amount, the amount of tin source is calculated based on the number of moles of tin it contains, the amount of selenium source is calculated based on the number of moles of selenium it contains, and the amount of alkali is calculated based on its own molar amount. The temperatures and times for the first and second stage hydrothermal reactions, as well as the temperature and time for calcination, are shown in Table 2.

[0078] Table 1

[0079] Table 2

[0080] Comparative Examples 1-4 After calcining the commercial molecular sieve at high temperature, 5g of it was added to a mixed solution consisting of tin dichloride, selenium dioxide and 100mL ethanol. The mixture was stirred evenly at room temperature. Then, 3mL of hydrazine hydrate was slowly added and stirred for 30 minutes. Triethylamine was then slowly added and stirred for another 30 minutes. The mixed solution was then transferred to a hydrothermal reactor with a polytetrafluoroethylene liner for hydrothermal reaction. The mixture was then naturally cooled to room temperature, filtered, washed with water, and dried at 100°C overnight.

[0081] The molar amounts of tin source, selenium source, and alkali are shown in Table 3. The amount of tin source is calculated as 1 mol based on the amount of tin it contains, the amount of selenium source is calculated based on the number of moles of selenium it contains, the amount of molecular sieve is calculated based on its own molar amount, and the amount of alkali is calculated based on its own molar amount. The temperature and time of the hydrothermal reaction, and the temperature and time of the calcination are shown in Table 3.

[0082] Table 3

[0083] Test case The tin selenide-supported mordenite molecular sieve catalysts prepared in Examples 1 to 17 and the catalysts prepared in Comparative Examples 1 to 4 were used for testing the production of ethanol from carbon dioxide: (1) Catalyst activation: Weigh 1 g of catalyst sample and put it into a stainless steel reaction tube. At the activation temperature of 190°C, pass in activation gas and activate for 12 hours. Then purge with nitrogen at the same temperature for 2 hours to complete the activation of the catalyst. (2) Ethanol synthesis: Carbon dioxide and hydrogen were introduced into a stainless steel reaction tube at 4.5 MPs and 190 °C. The carbon dioxide:hydrogen ratio was 2:5 (molar ratio) and the introduced carbon dioxide reacted with the activated catalyst. The total space velocity of the mixture was controlled at 5 h⁻¹. -1 The exhaust gas was analyzed online using gas chromatography to calculate the conversion rate of carbon dioxide and the selectivity of ethanol compounds. The condensate was collected and the product type was determined using nuclear magnetic resonance hydrogen spectroscopy.

[0084] Online gas chromatography analysis of tail gas was performed using an Agilent 8860A gas chromatograph manufactured by Agilent Technologies, USA. The product composition was quantitatively analyzed by area normalization. The test conditions were as follows: detection temperature 270℃, vaporization temperature 250℃; HP-5 capillary column (0.25 mm × 50 m); column temperature was controlled by a programmed temperature ramp method, holding at 60℃ for 3 min, then ramping to 200℃ at a rate of 7℃ / min and holding for 5 min.

[0085] In the embodiments of this application, the carbon dioxide conversion rate and the selectivity of ethanol compounds are calculated based on molar numbers: Carbon dioxide conversion rate % = (number of carbon moles of carbon dioxide in feed gas – number of carbon moles of ethanol compounds in product) / number of carbon moles of carbon dioxide in feed gas × 100% (calculated based on the number of carbon moles); Ethanol selectivity % = (number of carbon moles of ethanol in the product) / (number of carbon moles of carbon dioxide in the feed gas – number of carbon moles of ethanol in the product) × 100% (calculated based on the number of carbon moles); The test results are shown in Table 4.

[0086] Table 4

[0087] In summary, the data in the table shows that for the mordenite zeolite catalyst supported on tin selenide in the catalytic hydrogenation of carbon dioxide to ethanol, all preparation conditions affect its catalytic efficiency. The proven effects include: (1) The silicon-to-aluminum ratio of the mordenite catalyst supported on tin selenide will affect the carbon dioxide conversion rate and ethanol selectivity of the carbon dioxide hydrogenation to ethanol reaction. The higher the silicon-to-aluminum ratio, the higher the carbon dioxide conversion rate, but the corresponding ethanol selectivity will decrease.

[0088] (2) The ratio of tin to selenium in the mordenite catalyst supported on tin selenide will affect the carbon dioxide conversion rate and ethanol selectivity in the reaction of carbon dioxide hydrogenation to ethanol. The carbon dioxide conversion rate is highest when the ratio of tin to selenium is 1:1 and 1:2.

[0089] (3) The technical solution of this application is far superior to the tin selenide-supported mordenite catalyst prepared by using commercial mordenite molecular sieve in terms of carbon dioxide conversion rate. As a better effect, it can achieve a carbon dioxide conversion rate of more than 50% and an ethanol selectivity of more than 50%.

[0090] 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 supported tin selenide ferrite zeolite catalyst, characterized in that, include: A mixed solution containing silicon source, aluminum source, template agent and water is pre-crystallized to obtain silicon-aluminum gel; Under stirring conditions, a mixed solution containing tin source, selenium source and ethanol was slowly added to the silica-alumina gel in sequence, followed by the slow addition of alkali to obtain a mixed gel. The mixed gel was placed in a sealed container and subjected to hydrothermal crystallization. The product of the hydrothermal crystallization was washed with water, dried, and then calcined to obtain the supported tin selenide ferruginous zeolite catalyst.

2. The preparation method according to claim 1, characterized in that, The molar ratio of each component in the mixed solution containing silicon source, aluminum source, template agent, and water is as follows: Silicon source: Aluminum source: Template agent: Water = 1~100:1:0.5~50:10~2000; The amount of silicon source used is calculated based on the number of moles of silicon it contains; The amount of aluminum source used is calculated based on the number of moles of aluminum it contains; The amount of template agent used is calculated based on its own molar number; The amount of water used 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 aluminum source is selected from at least one of aluminum sulfate, aluminum chloride, aluminum powder, aluminum isopropoxide, and aluminum hydroxide; Preferably, the template agent 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 components in the mixed gel and their molar ratios with the aluminum source are as follows: Selenium source: Tin source: Alkali: Aluminum source = 1~5:1~5:0.1~0.5:1; The amount of tin source used is calculated based on the number of moles of tin it contains; The amount of selenium source used is calculated based on the number of moles of selenium it contains; The amount of alkali used is calculated based on its own molar quantity; The amount of aluminum source used is calculated based on the number of moles of aluminum in it; Preferably, the tin source is selected from at least one of tin nitrate, tin sulfate, and stannous chloride; Preferably, the selenium source is selected from at least one of selenium dioxide and potassium selenite; Preferably, the alkali is selected from at least one of triethylamine, ammonium carbonate, and diethylamine.

4. The preparation method according to claim 1, characterized in that, The pre-crystallization conditions are: temperature 50~60 °C, time 2~4 h.

5. The preparation method according to claim 1, characterized in that, After slowly adding a mixed solution containing tin source, selenium source and ethanol to the silica-alumina gel, stirring is maintained for 2-6 hours. Preferably, the stirring conditions include a stirring temperature of 50~70 °C.

6. The preparation method according to claim 1, characterized in that, The conditions for hydrothermal crystallization are: temperature 100~190 °C, time 8~72 h; Preferably, the hydrothermal crystallization conditions are: reacting at 80~170 °C for 8~48 h, and then reacting at 80~190 °C for 8~48 h.

7. The preparation method according to claim 2, characterized in that, The calcination conditions are: temperature 300~600 °C, time 2~8 h.

8. The supported tin selenide ferromagnetic zeolite catalyst prepared by the preparation method according to any one of claims 1 to 7, characterized in that, Its silicon-to-aluminum ratio is 5~100:

1.

9. The application of the supported tin selenide filament zeolite catalyst prepared by the preparation method according to any one of claims 1 to 7 or the supported tin selenide filament zeolite catalyst according to claim 8 in the production of ethanol from carbon dioxide, characterized in that, include: Ethanol is obtained by contacting raw materials containing hydrogen and carbon dioxide with a supported tin selenide ferruginous zeolite catalyst.

10. The application according to claim 9, characterized in that, The molar ratio of hydrogen to carbon dioxide in the raw material 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 3–6 h⁻¹. -1 .

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