Preparation method and application of sulfide ceramic membrane catalyst using waste vanadium titanium denitrification catalyst

Abstract

The present invention discloses a method for preparing a sulfided ceramic membrane catalyst using waste vanadium-titanium denitration catalyst and its application. The method is characterized by grinding the waste denitration catalyst into powder, adding a forming agent and a heavy metal ion curing agent to granulate, and directly calcining the granules at high temperature to form small ceramic membrane particles. The small ceramic membrane particles are then subjected to an oxygen-free sulfurization process in an SO2 reaction atmosphere. The sulfurized small ceramic membrane particles are then soaked in heated deionized water to remove alkaline metal ions. Finally, the small ceramic membrane particles are dried and subjected to a secondary oxygen sulfurization process to obtain a sulfided ceramic membrane catalyst. The sulfided ceramic membrane catalyst prepared by this method can not only effectively catalyze the desorption of CO2, but also enable the large-scale, high-value-added utilization of waste denitration catalysts, completely solving the problems of solid pollution and resource utilization of waste denitration catalysts.

Description

Technical Field

[0001] The present invention belongs to the technical field of hazardous waste recycling and carbon dioxide desorption, and specifically relates to a method for preparing a sulfide ceramic membrane catalyst using waste vanadium-titanium denitration catalyst and its application. Background Art

[0002] With the rapid development of industrialization, large-scale emissions of nitrogen oxides have caused numerous atmospheric pollution problems, including acid rain, photochemical smog, and haze. Selective oxidation-reduction technology (SCR) has been widely used in the field of denitrification. Currently, approximately 140,000 tons of SCR denitrification catalysts are discarded each year, which translates to a volume of up to 250,000 cubic meters. The regeneration or resource utilization of discarded denitrification catalysts has become an urgent environmental challenge. Conventional catalysts can usually be regenerated two to three times before being completely scrapped. In other words, catalyst regeneration is not actually the final treatment method. On this basis, the high-value-added resource utilization of discarded denitrification catalysts is a feasible and economical conversion method.

[0003] Among the existing patents for treating waste denitrification catalysts, patent CN104209148B prepares a mixed solution of sodium hydroxide, sodium xylene sulfonate, and fatty alcohol polyoxyethylene ether for alkaline washing of phosphorus-poisoned waste denitrification catalysts, and then regenerates them by soaking them in active components. Patent CN106807401B prepares a regeneration solution with soluble vanadium salts, soluble tungsten salts, and additives. The waste denitrification catalyst is subjected to roasting, leaching, extraction, stripping, soaking in a regeneration solution, and roasting to restore the catalytic performance to 90%. Patent CN112827354B discloses a method for regenerating a thallium-poisoned denitrification catalyst. Through soot blowing, ultrasonic bubbling treatment, acid leaching, active component impregnation, and roasting, the catalyst performance is significantly improved. The optimal catalyst achieves a denitrification efficiency of over 97% at 290°C. The aforementioned patents not only utilize multiple acids, alkalis, and organic liquids for cleaning, causing secondary environmental pollution, but also completely deactivate the catalyst after one or two regenerations, failing to fundamentally address the pollution problem of spent denitrification catalysts. Patent CN105347785B mixes waste denitrification catalysts with raw materials such as silicon source powder, aluminum source powder, a sintering promoter, and a vanadium solid solvent to produce titanium-based ceramics. Patent CN110981199A discloses a method for preparing a composite emulsifier for ceramics using treated spent denitrification catalyst as raw material, mixed with wollastonite, calcium carbonate, and a dispersant, and then ground. Patent CN202210384283.9 discloses a thermal resistance material and preparation method using a denitrification catalyst deactivated by alkali metal poisoning as raw material. While both of these solutions can completely render the catalyst harmless, they only fully utilize the TiO2 in the spent denitrification catalyst, leaving a low utilization rate for active components such as oxides like V2O5. These solutions are limited to low-value-added applications such as textile ceramics, building and sanitary ceramics, and thermal resistance materials.

[0004] Carbon dioxide (CO2) capture plays a key role in reducing CO2 emissions. Among the current carbon dioxide capture technologies, amine washing is considered to be the most mature technology and will dominate industrial applications in the short and medium term. However, the solvent regeneration process remains a key challenge, accounting for about two-thirds of operating costs. Therefore, any improvement in reducing energy use will help reduce capture costs. For example, patent CN113713571B discloses a method for enhancing carbon dioxide desorption by a monatomic fluid containing Cr. Industrial flue gas is passed into an absorption liquid containing a monatomic fluid containing Cr, and the CO2 in the flue gas is absorbed and the N2 is released; the solution after absorbing the flue gas is then passed into a reactor, and CO2 is desorbed under the action of electrical energy, thermal energy and chemical energy. The monatomic fluid contains Cr atoms, which enhances the thermoelectric effect of the monatomic fluid. The strong thermoelectric effect can enhance CO2 desorption, significantly reduce the desorption temperature, and thus reduce energy consumption.

[0005] In view of the current situation in China where a large number of waste vanadium titanium denitration catalysts are waiting to be treated and there is a lack of advanced means for safe disposal and resource utilization, the present invention innovatively proposes to use waste vanadium titanium denitration catalysts to prepare sulfide ceramic membrane catalysts and apply them to the field of carbon dioxide desorption. The main components of waste vanadium titanium denitration catalysts are titanium dioxide, vanadium pentoxide and tungsten oxide. In addition, they also contain some heavy metal impurities and ammonium sulfate attachments. The impurities in the waste vanadium titanium denitration catalysts are treated by special means, and only the three active substances of titanium dioxide, vanadium pentoxide and tungsten oxide are retained. These are used as raw materials to synthesize sulfide ceramic membrane catalysts, which are applied to the field of carbon dioxide desorption. By utilizing the rich acidic sites on the surface of the sulfide ceramic membrane catalyst, the CO2 desorption rate can be significantly improved and energy consumption can be reduced. The successful application of the present invention will not only completely solve the problem of handling waste vanadium titanium denitration catalysts, but also solve the problem of high energy consumption of carbon dioxide desorption, and has high economic value. Summary of the Invention

[0006] The purpose of the present invention is to provide a recycling solution to address the problem that the current treatment solution for waste vanadium-titanium denitrification catalysts is single and has low economic benefits; another purpose of the present invention is to provide a sulfide ceramic membrane catalyst to address the problem of high energy consumption of carbon dioxide desorption technology in the existing technology, thereby improving the desorption performance of CO2-rich amine solvents and reducing the energy consumption of CO2 desorption.

[0007] The technical solution of the present invention is: the waste vanadium titanium denitrification catalyst contains not only metal oxides such as TiO2, V2O5, WO3, but also heavy metal ions, ammonium bisulfate, alkali / alkaline earth metal ions and sulfates generated by the reaction of TiO2, V2O5, WO3 and SO2 (SO3). The present invention uses waste vanadium-titanium denitration catalysts with rich surface acidic sites as raw materials, and uses niobium pentoxide as a heavy metal ion curing agent to mix and roast with the waste vanadium-titanium denitration catalyst powder. The niobium pentoxide combines with heavy metal ions (such as As, Hg, Pt, etc.) in the waste catalyst to form a solid solution, thereby preventing the precipitation of heavy metal ions in subsequent experiments and causing pollution. The alkali / alkaline earth metal oxides in the waste catalyst are converted into soluble sulfates or sulfites through a primary anaerobic sulfidation, which is convenient for washing away with hot water. Finally, a secondary aerobic sulfidation is performed to convert part of the metal oxides such as TiO2 and V2O5 into sulfates, thereby further increasing the content of metal sulfates in the waste denitration catalyst, forming super acid sites on the surface of the sulfided ceramic membrane catalyst, and strengthening the proton-providing ability of the sulfided ceramic membrane catalyst, thereby improving the catalytic effect and reducing the energy consumption of desorption.

[0008] The technical solution of the present invention can be achieved by the following steps:

[0009] A method for preparing a sulfide ceramic membrane catalyst using waste vanadium-titanium denitration catalyst is as follows:

[0010] (1) Preparation of small particles of ceramic membrane

[0011] After the waste vanadium titanium denitrification catalyst is crushed, ground and sieved, a forming agent and a heavy metal ion curing agent are added and stirred evenly, the mixture is granulated and sieved, and then calcined at high temperature and ground into small ceramic membrane particles with a particle size of 0.01 to 2.0 mm;

[0012] (2) Oxygen-free sulfidation of small particles of ceramic membrane

[0013] The ceramic membrane particles obtained in step (1) are placed in a tubular atmosphere furnace, a mixed gas of SO2 and N2 is introduced, and oxygen-free sulfurization is performed at a high temperature to obtain oxygen-free sulfurized ceramic membrane particles;

[0014] (3) Preparation of sulfide ceramic membrane catalyst

[0015] The oxygen-free sulfide ceramic membrane particles obtained in step (2) are placed in heated deionized water and soaked for 0.5 to 1 hour, then taken out and dried and soaked in deionized water for a second time for 0.5 to 1 hour. After the second soaking, the soaked oxygen-free sulfide ceramic membrane particles are placed in a tubular atmosphere furnace, a mixed gas of SO2, O2 and N2 is introduced, and a secondary aerobic sulfidation is carried out at high temperature to finally obtain a sulfide ceramic membrane catalyst.

[0016] In the technical solution of the present invention: the waste vanadium titanium denitration catalyst described in step (1) uses TiO2 as a carrier, WO3 and V2O5 as active components, and the rest are additives; wherein, the TiO2 carrier is 75% to 90% of the content of the waste vanadium titanium denitration catalyst, and the active components WO3 and V2O5 are 1% to 4% and 1% to 3% of the content of the waste vanadium titanium denitration catalyst, respectively.

[0017] In the technical solution of the present invention: the molding agent in step (1) is a polyvinyl alcohol solution with a mass fraction of 5 to 15%, and the heavy metal ion curing agent is niobium pentoxide;

[0018] Preferably, the mass ratio of the waste vanadium titanium denitrification catalyst, the forming agent and the heavy metal ion curing agent in step (1) is 1: (0.1-0.15): (0.005-0.01).

[0019] It is further preferred that the small particles of the ceramic membrane in step (1) are spherical particles of 1.4 to 2.0 mm.

[0020] In the technical solution of the present invention: the temperature of the high-temperature calcination in step (1) is 1200-1500° C., and the time of the high-temperature calcination is 12-24 hours.

[0021] In the technical solution of the present invention: the volume ratio of SO2 and N2 in the mixed gas described in step (2) is (10-20): (80-90), and the flow rate of the mixed gas is 20-50 mL / min.

[0022] In the technical solution of the present invention: the temperature for the anaerobic vulcanization at high temperature in step (2) is 600-800° C., and the time for the anaerobic vulcanization at high temperature is 4-6 hours.

[0023] In the technical solution of the present invention: the volume ratio of SO2, O2 and N2 in the mixed gas described in step (3) is (5-20): (5-20): (70-85), and the flow rate of the mixed gas is 20-50 mL / min.

[0024] In the technical solution of the present invention: the temperature of the secondary aerobic vulcanization at high temperature in step (3) is 600-800° C., and the time of the anaerobic vulcanization at high temperature is 4-6 hours.

[0025] A sulfide ceramic membrane catalyst is prepared using waste vanadium-titanium denitration catalyst, and the catalyst is prepared using the above method.

[0026] In the technical solution of the present invention, the above method is used to prepare a sulfide ceramic membrane catalyst using waste vanadium-titanium denitration catalyst for use in catalyzing CO2 desorption.

[0027] Beneficial effects:

[0028] This invention innovatively uses waste vanadium-titanium denitration catalysts as raw materials to synthesize sulfided ceramic membrane catalysts for use in the field of carbon dioxide desorption. By utilizing the abundant acidic sites on the surface of the vanadium-titanium denitration catalyst and the sulfate formed after waste, which significantly increases the number of surface acidic sites, the desorption rate of CO2 is significantly improved and the energy consumption of the reaction is reduced. This method completely solves the problem of disposing of waste vanadium-titanium denitration catalysts and enables their high-value-added reuse. This method uses common raw materials, has a simple process, is environmentally friendly, and has high economic value and broad market application prospects. DETAILED DESCRIPTION

[0029] The present invention will be further described below with reference to the following examples, but the scope of protection of the present invention is not limited thereto: Example 1

[0030] (1) Preparation of waste denitration catalyst: Use waste vanadium titanium denitration catalyst after use in thermal power plants and whose activity is reduced to below 30% as raw material. The carrier of the waste vanadium titanium denitration catalyst is 75% TiO2, and the active components WO3 and V2O5 are 1% and 3% of the content of the waste vanadium titanium denitration catalyst respectively.

[0031] (2) Preparation of ceramic membrane granules: Grind 100g of spent denitration catalyst to a particle size of less than 0.075mm (200 mesh) for later use. Weigh 0.5g of niobium pentoxide and mix it evenly with the spent denitration catalyst powder. Weigh 10.0g of a 15% polyvinyl alcohol solution and add it to the mixed powder. Repeatedly knead and granulate to select particles with a particle size of 1.4-2.0mm (9-12 mesh). Calcinate at 1200°C for 12h to obtain ceramic membrane granules for later use.

[0032] (3) Oxygen-free sulfurization of ceramic membrane particles: The ceramic membrane particles obtained in step (2) are placed in a tubular atmosphere furnace and a mixed gas (V N2 :V SO2 =20:90, flow rate 35 ml / min) and oxygen-free sulfurization was carried out at 700°C for 6 hours to obtain oxygen-free sulfurized ceramic membrane small particles.

[0033] (4) Preparation of sulfide ceramic membrane catalyst: The oxygen-free sulfide ceramic membrane particles obtained in step (3) were placed in 1000 ml of 60°C deionized water and soaked for 0.5 h, then taken out and dried at 80°C for 6 h. Then, they were soaked in 2000 ml of 80°C deionized water for a second time for 0.6 h. After the second soaking, the oxygen-free sulfide ceramic membrane particles were placed in a tubular atmosphere furnace and a mixed gas (flow rate 20 ml / min, V N2 :V SO2 :V O2 =80:10:8), and secondary aerobic sulfidation was carried out at 700 °C for 6 h to finally obtain a sulfided ceramic membrane catalyst.

[0034] Example 2

[0035] (1) Preparation of waste denitration catalyst: Use waste vanadium titanium denitration catalyst after use in thermal power plants and whose activity is reduced to below 30% as raw material. The carrier of the waste vanadium titanium denitration catalyst is 80% TiO2, and the active components WO3 and V2O5 are 2% and 3% of the content of the waste vanadium titanium denitration catalyst respectively.

[0036] (2) Preparation of ceramic membrane granules: Grind 100g of spent denitration catalyst to a particle size of less than 0.075mm (200 mesh) for later use. Weigh 0.7g of niobium pentoxide and mix it evenly with the spent denitration catalyst powder. Weigh 12.0g of a 10% polyvinyl alcohol solution and add it to the mixed powder. Repeatedly knead and granulate to select particles with a particle size of 1.4-2.0mm (9-12 mesh). Calcinate at 1400°C for 15h to obtain ceramic membrane granules for later use.

[0037] (3) Oxygen-free sulfurization of ceramic membrane particles: The ceramic membrane particles obtained in step (2) are placed in a tubular atmosphere furnace and a mixed gas (V N2 :V SO2 =10:80, flow rate 25 ml / min) and oxygen-free sulfurization was carried out at 600°C for 6 hours to obtain oxygen-free sulfurized ceramic membrane small particles.

[0038] (4) Preparation of sulfide ceramic membrane catalyst: The oxygen-free sulfide ceramic membrane particles obtained in step (3) were placed in 1000 ml of 80°C deionized water and soaked for 0.6 h, then taken out and dried at 90°C for 6 h. Then, they were soaked in 2000 ml of 80°C deionized water for a second time for 0.6 h. After the second soaking, the oxygen-free sulfide ceramic membrane particles were placed in a tubular atmosphere furnace and a mixed gas (flow rate 25 ml / min, V N2 :V SO2 :V O2 =75:10:8), and secondary aerobic sulfidation was carried out at 600 °C for 6 h to finally obtain a sulfided ceramic membrane catalyst.

[0039] Example 3

[0040] (1) Preparation of waste denitration catalyst: Use waste vanadium titanium denitration catalyst after use in thermal power plants and whose activity is reduced to below 30% as raw material. The carrier of the waste vanadium titanium denitration catalyst is 85% TiO2, and the active components WO3 and V2O5 are 3% and 2% of the content of the waste vanadium titanium denitration catalyst respectively.

[0041] (2) Preparation of ceramic membrane granules: Grind 100g of spent denitration catalyst to a particle size of less than 0.075mm (200 mesh) for later use. Weigh 0.9g of niobium pentoxide and mix it evenly with the spent denitration catalyst powder. Weigh 15g of a 5% polyvinyl alcohol solution and add it to the mixed powder. Repeatedly knead and granulate to select particles with a particle size of 1.4-2.0mm (9-12 mesh). Calcinate at 1300°C for 20h to obtain ceramic membrane granules for later use.

[0042] (3) Oxygen-free sulfurization of ceramic membrane particles: The ceramic membrane particles obtained in step (2) are placed in a tubular atmosphere furnace and a mixed gas (V N2 :V SO2 =20:80, flow rate 20 ml / min) and oxygen-free sulfurization was carried out at 600°C for 4 hours to obtain oxygen-free sulfurized ceramic membrane small particles.

[0043] (4) Preparation of sulfide ceramic membrane catalyst: The oxygen-free sulfide ceramic membrane particles obtained in step (3) were placed in 1000 ml of 80°C deionized water and soaked for 0.5 h, then taken out and dried at 100°C for 4 h. Then, they were soaked in 2000 ml of 60°C deionized water for a second time for 0.8 h. After the second soaking, the oxygen-free sulfide ceramic membrane particles were placed in a tubular atmosphere furnace and a mixed gas (flow rate 50 ml / min, V N2 :V SO2 :V O2 =80:15:5), and secondary aerobic sulfidation was carried out at 800 °C for 4 h to finally obtain a sulfided ceramic membrane catalyst.

[0044] Example 4

[0045] (1) Preparation of waste denitration catalyst: Use waste vanadium titanium denitration catalyst after use in thermal power plants and whose activity is reduced to below 30% as raw material. The carrier of the waste vanadium titanium denitration catalyst is 85% TiO2, and the active components WO3 and V2O5 are 3% and 2% of the content of the waste vanadium titanium denitration catalyst respectively.

[0046] (2) Preparation of ceramic membrane granules: Grind 100g of spent denitration catalyst to a particle size of less than 0.075mm (200 mesh) for later use. Weigh 1.0g of niobium pentoxide and mix it evenly with the spent denitration catalyst powder. Weigh 10g of a 10% polyvinyl alcohol solution and add it to the mixed powder. Repeatedly knead and granulate to select particles with a particle size of 1.4-2.0mm (9-12 mesh). Calcinate at 1300°C for 24h to obtain ceramic membrane granules for later use.

[0047] (3) Oxygen-free sulfurization of ceramic membrane particles: The ceramic membrane particles obtained in step (2) are placed in a tubular atmosphere furnace and a mixed gas (V N2 :V SO2=15:85, flow rate 45 ml / min) and oxygen-free sulfurization was carried out at 800°C for 5 hours to obtain oxygen-free sulfurized ceramic membrane small particles.

[0048] (4) Preparation of sulfide ceramic membrane catalyst: The oxygen-free sulfide ceramic membrane particles obtained in step (3) were placed in 1000 ml of 80°C deionized water and soaked for 0.7 h, then taken out and dried at 80°C for 5 h. Then, they were soaked in 2000 ml of 70°C deionized water for a second time for 1 h. After the second soaking, the oxygen-free sulfide ceramic membrane particles were placed in a tubular atmosphere furnace and a mixed gas (flow rate 40 ml / min, V N2 :V SO2 :V O2 =85:20:8), and secondary aerobic sulfidation was carried out at 600 °C for 5 h to finally obtain a sulfided ceramic membrane catalyst.

[0049] Example 5

[0050] (1) Preparation of waste denitration catalyst: Use waste vanadium titanium denitration catalyst after use in thermal power plants and whose activity is reduced to below 30% as raw material. The carrier of the waste vanadium titanium denitration catalyst is 90% TiO2, and the active components WO3 and V2O5 are 4% and 1% of the content of the waste vanadium titanium denitration catalyst respectively.

[0051] (2) Preparation of ceramic membrane small particles: Grind 100g of spent denitration catalyst to a particle size of less than 0.075mm (200 mesh) for later use. Weigh 0.5g of niobium pentoxide and the spent denitration catalyst powder and mix them evenly. Weigh 10g of a 12% polyvinyl alcohol solution and add it to the mixed powder. Repeatedly knead and granulate to select particles with a particle size of 1.4-2.0mm (9-12 mesh). Calcinate at 1500°C for 15h to obtain ceramic membrane small particles for later use.

[0052] (3) Oxygen-free sulfurization of ceramic membrane particles: The ceramic membrane particles obtained in step (2) are placed in a tubular atmosphere furnace and a mixed gas (V N2 :V SO2 =10:90, flow rate 50 ml / min) and oxygen-free sulfurization was carried out at 800°C for 6 hours to obtain oxygen-free sulfurized ceramic membrane small particles.

[0053] (4) Preparation of sulfide ceramic membrane catalyst: The oxygen-free sulfide ceramic membrane particles obtained in step (3) were placed in 1000 ml of 60°C deionized water and soaked for 1 hour, then taken out and dried at 100°C for 6 hours. Then, they were soaked in 2000 ml of 70°C deionized water for a second time for 0.5 hours. After the second soaking, the oxygen-free sulfide ceramic membrane particles were placed in a tubular atmosphere furnace and a mixed gas (flow rate 30 ml / min, V N2 :V SO2 :V O2=70:20:10), and secondary aerobic sulfidation was carried out at 700 °C for 5 h to finally obtain a sulfided ceramic membrane catalyst.

[0054] Example 6

[0055] (1) Preparation of small particles of ceramic membrane: The waste vanadium titanium denitrification catalyst whose activity has been reduced to less than 30% after being used in thermal power plants is used as raw material. The carrier of the waste vanadium titanium denitrification catalyst is 90% TiO2, and the active components WO3 and V2O5 are 3.5% and 1.5% of the content of the waste vanadium titanium denitrification catalyst respectively.

[0056] (2) Preparation of ceramic membrane small particles: Grind 100g of spent denitration catalyst to a particle size of less than 0.075mm (200 mesh) for later use. Weigh 0.5g of niobium pentoxide and the spent denitration catalyst powder and mix them evenly. Weigh 10g of a 12% polyvinyl alcohol solution and add it to the mixed powder. Repeatedly knead and granulate to select particles with a particle size of 1.4-2.0mm (9-12 mesh). Calcinate at 1500°C for 15h to obtain ceramic membrane small particles for later use.

[0057] (3) Oxygen-free sulfurization of ceramic membrane particles: The ceramic membrane particles obtained in step (2) are placed in a tubular atmosphere furnace and a mixed gas (V N2 :V SO2 =10:90, flow rate 50 ml / min) and oxygen-free sulfurization was carried out at 800°C for 6 hours to obtain oxygen-free sulfurized ceramic membrane small particles.

[0058] (4) Preparation of sulfide ceramic membrane catalyst: The oxygen-free sulfide ceramic membrane particles obtained in step (3) were placed in 1000 ml of 60°C deionized water and soaked for 1 hour, then taken out and dried at 100°C for 6 hours. Then, they were soaked in 2000 ml of 70°C deionized water for a second time for 0.5 hours. After the second soaking, the oxygen-free sulfide ceramic membrane particles were placed in a tubular atmosphere furnace and a mixed gas (flow rate 30 ml / min, V N2 :V SO2 :V O2 =70:20:10), and secondary aerobic sulfidation was carried out at 700 °C for 5 h to finally obtain a sulfided ceramic membrane catalyst.

[0059] Performance Evaluation: 300ml of monoethanolamine was mixed with 700ml of deionized water to form a mixed solution. Pure CO2 was then bubbled into the mixed solution at 10ml / min for 1000 minutes to form a CO2-rich amine solution. Samples were taken and the CO2 content was approximately 0.36mol / L. 100ml of the CO2-rich amine solution was transferred to a flask, 2g of a sulfide ceramic membrane catalyst was added, and the outlet of the flask was connected to a condenser for reflux. The carbon dioxide was then collected using the drainage method using ethanol as the drainage solution. The flask was transferred to a 100°C oil bath. After 30 minutes of reaction, the amount of carbon dioxide collected was observed, and the residual CO2 concentration in the amine solution was measured.

[0060] Blank sample: Mix 30ml of monoethanolamine with 70ml of deionized water to prepare a mixed solution. Then, using the bubbling method, continuously introduce pure CO2 into the mixed solution at 10ml / min for 100 minutes to form a CO2-rich amine solution. Samples were taken for detection of CO2 content, which was approximately 0.36mol / L. The CO2-rich amine solution was transferred to a flask, and the outlet of the flask was connected to a condenser for condensation and reflux. The carbon dioxide was then collected using the drainage method using ethanol as the drainage solution. The flask was transferred to a 100℃ oil bath. After reacting for 30 minutes, the amount of carbon dioxide gas collected was observed, and the residual CO2 concentration in the amine solution was measured.

[0061] The performance evaluation results are shown in the following table:

[0062]

Claims

1. A method for preparing a sulfide ceramic membrane catalyst using waste vanadium-titanium denitration catalyst, characterized by: The preparation method is as follows: (1) Preparation of small particles of ceramic membrane After the waste vanadium titanium denitrification catalyst is crushed, ground and sieved, a forming agent and a heavy metal ion curing agent are added and stirred evenly. The mixture is granulated and sieved, calcined at high temperature, and ground into small ceramic membrane particles with a particle size of 0.01-2.0 mm; the heavy metal ion curing agent is niobium pentoxide; (2) Oxygen-free sulfidation of small particles of ceramic membrane The ceramic membrane particles obtained in step (1) are placed in a tubular atmosphere furnace, a mixed gas of SO2 and N2 is introduced, and oxygen-free sulfurization is performed at a high temperature to obtain oxygen-free sulfurized ceramic membrane particles; (3) Preparation of sulfide ceramic membrane catalyst The oxygen-free sulfide ceramic membrane particles obtained in step (2) are placed in heated deionized water and soaked for 0.5 to 1 hour, then taken out and dried and soaked in deionized water for a second time for 0.5 to 1 hour. After the second soaking, the soaked oxygen-free sulfide ceramic membrane particles are placed in a tubular atmosphere furnace, a mixed gas of SO2, O2 and N2 is introduced, and a secondary aerobic sulfidation is carried out at high temperature to finally obtain a sulfide ceramic membrane catalyst.

2. The preparation method according to claim 1, wherein: The waste vanadium titanium denitration catalyst described in step (1) uses TiO2 as a carrier, WO3 and V2O5 as active components, and the rest are additives; wherein the TiO2 carrier is 75% to 90% of the content of the waste vanadium titanium denitration catalyst, and the active components WO3 and V2O5 are 1% to 4% and 1% to 3% of the content of the waste vanadium titanium denitration catalyst, respectively.

3. The preparation method according to claim 1, wherein: The forming agent in step (1) is a polyvinyl alcohol solution with a mass fraction of 5 to 15%.

4. The preparation method according to claim 3, wherein: The mass ratio of the waste vanadium titanium denitrification catalyst, the forming agent and the heavy metal ion curing agent in step (1) is 1: (0.1-0.15): (0.005-0.01).

5. The preparation method according to claim 1, wherein: The high-temperature calcination temperature in step (1) is 1200-1500° C., and the high-temperature calcination time is 12-24 hours.

6. The preparation method according to claim 1, wherein: The volume ratio of SO2 and N2 in the mixed gas described in step (2) is (10~20): (80~90), and the flow rate of the mixed gas is 20~50mL / min.

7. The preparation method according to claim 1, wherein: The temperature for the anaerobic vulcanization at high temperature in step (2) is 600-800° C., and the time for the anaerobic vulcanization at high temperature is 4-6 hours.

8. The preparation method according to claim 1, wherein: The volume ratio of SO2, O2 and N2 in the mixed gas described in step (3) is (5-20): (5-20): (70-85), and the flow rate of the mixed gas is 20-50 mL / min.

9. The preparation method according to claim 1, wherein: The temperature of the secondary aerobic vulcanization at high temperature in step (3) is 600-800° C., and the time of the secondary aerobic vulcanization at high temperature is 4-6 hours.

10. A method for preparing a sulfide ceramic membrane catalyst using waste vanadium-titanium denitration catalyst, characterized in that: The catalyst is prepared by the method described in any one of items 1 to 9.

11. Use of the sulfide ceramic membrane catalyst prepared by using waste vanadium-titanium denitration catalyst as claimed in claim 10 in catalytic CO2 desorption.

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