Preparation method of zirconium oxide catalyst and application of zirconium oxide catalyst in catalytic co-production of hydrogen and carbon monoxide

Abstract

The invention discloses a preparation method of a zirconium oxide catalyst and application of the zirconium oxide catalyst in catalytic co-production of hydrogen and carbon monoxide, and belongs to the technical field of resource recovery, and the preparation method comprises the following steps: (1) dissolving a zirconium source and a complexing agent in water, and stirring at a high speed to obtain a clear solution; (2) dropwise adding alkali liquor into the solution obtained in the step (1) to adjust the pH value of the solution, then adding a dispersing agent, and refluxing and stirring the obtained solution for 10-12 hours at a certain temperature; (3) adding ammonium bicarbonate into the solution obtained in the step (2), then transferring the solution into a crystallization kettle, and crystallizing at a certain temperature; (4) filtering, washing, drying and grinding the product obtained in the step (3) into powder, and then putting the powder into dielectric barrier discharge plasma equipment for treatment; and (5) roasting the treated sample obtained in the step (4) in a muffle furnace to obtain the zirconium oxide catalyst. The catalyst is simple in preparation method, high in repetition rate and suitable for large-scale industrial production.

Description

Technical Field

[0001] The invention belongs to the technical field of resource recovery, and specifically relates to a method for preparing a zirconium oxide catalyst and an application of the catalyst in catalytically co-producing hydrogen and carbon monoxide. Background Art

[0002] Hydrogen sulfide (H 2 H) is a highly toxic gas with a rotten egg smell. It will corrode transmission pipelines and process equipment in the presence of moisture. It is also a poison for many industrial metal-based catalysts. The oxysulfides generated by its combustion are also components that cause acid rain. 2 S is widely present in acidic natural gas reservoirs. In addition, a large amount of H2O2 is also produced by desulfurization in petroleum refining, coal processing and other chemical synthesis processes. 2 S gas. Carbon dioxide (CO 2 ) is a key greenhouse gas that affects the carbon neutrality process. Industrial CO 2 The main sources include thermal power generation, cement production, petrochemicals, coal chemical industry and many other processes. Both will have a negative impact on society and the environment. Therefore, it is necessary to adopt a low-carbon and green way to effectively capture H 2 The hydrogen and sulfur resources contained in S can realize H 2 S and CO 2 Co-transformation is a technical problem to be solved.

[0003] Traditional H 2 The S treatment technology is the Claus process, which is to convert H 2 S is converted into water and elemental sulfur. This desulfurization process converts the raw gas CO 2 The content is limited, the energy consumption is high, the carbon emissions are large and it is not environmentally friendly, wasting H 2 Hydrogen resources in S.

[0004] If we can directly utilize the acid gas (H 2 S and CO 2 ), directly converting to produce hydrogen and other high-value products without separation can not only greatly reduce the costs caused by complex separation processes, but also synergistically recover hydrogen resources in acidic gases. Summary of the invention

[0005] As one aspect of the present invention, the present invention provides a method for preparing a zirconium oxide catalyst, which comprises the following steps: (1) dissolving a zirconium source and a complexing agent in water, wherein the zirconium ion concentration in the obtained solution is 0.05-0.5 mol / L, and the molar ratio of the complexing agent to the zirconium salt is (0.5-5):1; (2) adjusting the pH to 6-9, and reflux with stirring at 90-110°C for 10-12 hours; (3) adding ammonium bicarbonate and transferring the resulting solution to a crystallization kettle for crystallization for 24 to 48 hours; (4) filtering, washing, drying and grinding the product obtained in step (3) into powder, placing the powder into a dielectric barrier discharge plasma device at a discharge power of 80 to 100 W for 3 to 8 hours; (5) calcining the product obtained in step (4) to obtain a zirconium oxide catalyst; The complexing agent is one or more of diethanolamine, triethanolamine, ethylenediaminetetraacetate, diethylenetriaminepentacarboxylate, citric acid, and tartaric acid; The zirconium salt includes one of zirconium oxychloride, zirconium nitrate or zirconium oxynitrate.

[0006] As a preferred embodiment of the method for preparing the zirconium oxide catalyst of the present invention: step (2) further comprises adding a dispersant after adjusting the pH to 6-9, wherein the dispersant is one or more of cetyltrimethylammonium bromide, polyethylene glycol, sodium dodecylbenzene sulfonate, and polyvinyl pyrrolidone.

[0007] As a preferred embodiment of the method for preparing the zirconium oxide catalyst of the present invention: in step (2), the concentration of the dispersant is 0.1wt%-5wt%.

[0008] As a preferred embodiment of the method for preparing the zirconium oxide catalyst of the present invention, the crystallization temperature is 140-180°C.

[0009] As a preferred embodiment of the method for preparing the zirconium oxide catalyst of the present invention: in step (4), the powder is placed in a dielectric barrier discharge plasma device and hydrogen is introduced at a rate of 10-20 ml / min to perform dielectric barrier discharge.

[0010] As a preferred embodiment of the method for preparing the zirconium oxide catalyst of the present invention: in step (5), the calcination temperature is 400-900° C. and the calcination time is 3-8 hours.

[0011] The present invention also provides application of the catalyst prepared by the preparation method of the zirconium oxide catalyst in catalyzing the co-production of hydrogen and carbon monoxide by carbon dioxide and hydrogen sulfide.

[0012] Specifically, carbon dioxide and hydrogen sulfide gas are introduced under an inert atmosphere, and a plasma device is turned on for reaction. The discharge power of the plasma device is 120-180W and the frequency is 10-30 kHz.

[0013] Specifically, the inert atmosphere includes nitrogen, the volume percentage of hydrogen sulfide in the reaction gas is 34%-49%, the volume percentage of carbon dioxide is 1%-16%; the volume percentage of nitrogen is 40-50%; the reaction temperature is 120°C-350°C, the space velocity is 100-2000h -1 , the reaction pressure is 0.1-0.3MPa.

[0014] The beneficial effects of the present invention are as follows: 2 S and CO 2 As raw materials, by increasing the oxygen vacancies of zirconium oxide catalyst, the basicity and redox ability of the catalyst are improved, thereby enhancing the dissociation ability of hydrogen sulfide. The microspherical morphology further increases the specific surface area of ​​the catalyst, enhancing the H 2 S and CO 2 The adsorption of H is increased, thereby improving the reaction conversion rate. Through the plasma-assisted zirconia catalyst reaction, more excited species are formed, further enhancing the H 2 S and CO 2 The catalyst of the present invention is vacancy-rich microspherical zirconium dioxide, and the catalyst preparation process is simple, the cost is low, and it is easy to mass produce. The mesoporous structure of the catalyst is conducive to protecting the active sites and delaying the clogging of the catalyst pores by carbon deposition. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the technical solution of the embodiment of the present invention, the following is a brief introduction to the drawings required for describing the embodiment, wherein: Figure 1 This is a schematic diagram of a hydrogen production device using carbon dioxide and hydrogen sulfide according to the present invention; Figure 1 In the figure, 1-reaction tube, 2-high voltage electrode, 3-air inlet, 4-air outlet, 5-ground electrode, 6-catalyst filling chamber, 7-heating furnace, 8-export cold trap.

[0016] Figure 2 is the X-ray diffraction spectrum of the zirconium oxide catalyst of Example 4 of the present invention; Figure 3 is an X-ray diffraction spectrum of sulfur collected in a cold trap of a hydrogen production device using carbon dioxide and hydrogen sulfide in Example 4 of the present invention; Figure 4 is a SEM image of the zirconium oxide catalyst of Example 4 of the present invention; Figure 5 It is a nitrogen adsorption-desorption curve diagram of the zirconium oxide catalyst in Example 4 of the present invention. DETAILED DESCRIPTION

[0017] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are described in detail below in conjunction with specific embodiments.

[0018] Embodiment 1: 13.57g zirconium nitrate was weighed and dissolved in 100ml water, 4.21g diethanolamine was added, and a clear solution was obtained by stirring at 50°C, followed by dropwise addition of sodium hydroxide solution, pH was adjusted to 7, 2.34g polyethylene glycol (average molecular weight 300) was added, and then refluxed at 110°C for 12h, and then ammonium bicarbonate was added to the obtained solution, and then the solution was transferred to a crystallization kettle with a polytetrafluoroethylene liner and crystallized at 180°C for 48h. After the crystallization, the obtained product was filtered, washed several times, dried and ground into powder, and then placed in a dielectric barrier discharge low-temperature plasma device for treatment under a hydrogen atmosphere with a discharge power of 80W for 6h, and finally the obtained initial product was calcined at 400°C in a muffle furnace for 6h. The catalyst was named ZR1.

[0019] Embodiment 2: 9.24 g of zirconium oxynitrate was weighed and dissolved in 100 ml of water, 4.21 g of diethanolamine was added, and a clear solution was obtained by stirring at 50°C, followed by dropwise addition of sodium hydroxide solution, pH was adjusted to 7, 2.34 g of polyethylene glycol (average molecular weight 300) was added, and then refluxed at 110°C for 12 h. After completion, ammonium bicarbonate was added to the obtained solution, and then the solution was transferred to a crystallization kettle with a polytetrafluoroethylene liner and crystallized at 180°C for 48 h. After the crystallization, the obtained product was filtered, washed several times, dried and ground into powder, and then placed in a dielectric barrier discharge low-temperature plasma device for treatment under a hydrogen atmosphere with a discharge power of 80 W for 6 h. Finally, the obtained initial product was calcined at 400°C in a muffle furnace for 6 h. The catalyst was named ZR2.

[0020] Embodiment 3: 12.89g zirconium oxychloride was weighed and dissolved in 100ml water, 4.21g diethanolamine was added, and a clear solution was obtained by stirring at 50°C, followed by dropwise addition of sodium hydroxide solution, pH was adjusted to 7, 2.34g polyethylene glycol (average molecular weight 300) was added, and then refluxed at 110°C for 12h, and then ammonium bicarbonate was added to the obtained solution, and then the solution was transferred to a crystallization kettle with a polytetrafluoroethylene liner and crystallized at 180°C for 48h. After the crystallization, the obtained product was filtered, washed several times, dried and ground into powder, and then placed in a dielectric barrier discharge low-temperature plasma device for treatment under a hydrogen atmosphere with a discharge power of 60W for 6h, and finally the obtained primary product was calcined at 400°C in a muffle furnace for 6h. The catalyst was named ZR3.

[0021] Embodiment 4: 12.89g zirconium oxychloride was weighed and dissolved in 100ml water, 4.21g diethanolamine was added, and a clear solution was obtained by stirring at 50°C, followed by dropwise addition of sodium hydroxide solution, pH was adjusted to 7, 2.34g polyethylene glycol (average molecular weight 300) was added, and then refluxed at 110°C for 12h, and then ammonium bicarbonate was added to the obtained solution, and then the solution was transferred to a crystallization kettle with a polytetrafluoroethylene liner and crystallized at 180°C for 48h. After the crystallization, the obtained product was filtered, washed several times, dried and ground into powder, and then placed in a dielectric barrier discharge low-temperature plasma device for treatment under a hydrogen atmosphere with a discharge power of 80W for 6h, and finally the obtained primary product was calcined at 400°C in a muffle furnace for 6h. The catalyst was named ZR4.

[0022] Embodiment 5: 12.89g zirconium oxychloride was weighed and dissolved in 100ml water, 8.41g citric acid was added, and a clear solution was obtained by stirring at 50°C, followed by dropwise addition of sodium hydroxide solution, pH was adjusted to 7, 2.34g polyethylene glycol (average molecular weight 300) was added, and then refluxed at 110°C for 12h, and then ammonium bicarbonate was added to the obtained solution, and then the solution was transferred to a crystallization kettle with a polytetrafluoroethylene liner and crystallized at 180°C for 48h. After the crystallization, the obtained product was filtered, washed several times, dried and ground into powder, and then placed in a dielectric barrier discharge low-temperature plasma device for treatment under a hydrogen atmosphere with a discharge power of 80W for 6h, and finally the obtained primary product was calcined at 400°C in a muffle furnace for 6h. The catalyst was named ZR5.

[0023] Embodiment 6: 12.89g zirconium oxychloride was weighed and dissolved in 100ml water, 4.21g diethanolamine was added, and a clear solution was obtained by stirring at 50°C, followed by dropwise addition of sodium hydroxide solution, pH was adjusted to 7, 2.34g polyvinyl pyrrolidone (8000, K16-18) was added, and then refluxed at 110°C for 12h, and then ammonium bicarbonate was added to the obtained solution, and then the solution was transferred to a crystallization kettle with a polytetrafluoroethylene liner and crystallized at 180°C for 48h. After the crystallization, the obtained product was filtered, washed several times, dried and ground into powder, and then placed in a dielectric barrier discharge low-temperature plasma device for treatment under a hydrogen atmosphere with a discharge power of 80W for 6h, and finally the obtained primary product was calcined at 400°C in a muffle furnace for 6h. The catalyst was named ZR6.

[0024] Comparative Example 1: Commercial zirconium oxide (Aladdin), named ZR7.

[0025] Comparative Example 2: Zirconium oxide prepared by direct calcination of zirconium nitrate. The specific preparation process is as follows: weigh 20g of zirconium nitrate and calcine it in a muffle furnace at 500°C for 5h to obtain a sample. The catalyst is named ZR8.

[0026] The catalyst prepared in each of the above embodiments is placed in a reaction chamber of a reactor made of corundum material, and after nitrogen is introduced to remove oxygen in the reactor, a mixed gas of hydrogen sulfide, carbon dioxide and nitrogen is introduced, wherein the volume percentage of hydrogen sulfide in the mixed gas is 34%, the volume percentage of carbon dioxide is 16%, and the volume percentage of nitrogen is 50%, the mixed gas flow rate is 100 ml / min, the reaction temperature is 150° C., the reaction pressure is 0.2 MPa, and a plasma power supply connected to a high voltage electrode and a grounding electrode is turned on, and the voltage is adjusted so that the input power is 180 W and the frequency is 10 kHz. The reaction results are shown in Table 1.

[0027] Table 1 Conversion rate of hydrogen sulfide and carbon dioxide and ratio of hydrogen to carbon monoxide in the product

[0028] As can be seen from Table 1, the catalysts prepared in Examples 1 to 6 have significantly higher hydrogen sulfide conversion rates and carbon dioxide conversion rates than those in Comparative Examples 1 to 2, which solves the technical problem of low carbon dioxide conversion rate and achieves co-production of hydrogen and carbon monoxide, thereby reducing the molar ratio of hydrogen to carbon monoxide, that is, increasing the carbon monoxide content in the product. Among them, the catalyst prepared in Example 4 has the best catalytic effect.

[0029] The ZR5 catalyst is placed in the reaction chamber of the reactor made of corundum, and nitrogen is introduced to remove the oxygen in the reactor, and then hydrogen sulfide, carbon dioxide and nitrogen are introduced, wherein the volume percentage of hydrogen sulfide in the mixed gas is 34%, the volume percentage of carbon dioxide is 16%, the volume percentage of nitrogen in the mixed gas is 50%, the mixed gas flow rate is 100ml / min, the reaction temperature is 150°C, the reaction pressure is 0.2MPa, and the plasma power supply connected to the high-voltage electrode and the grounding electrode is turned on, and the initial voltage is adjusted to 30 kV and the frequency is 10 kHz. The input power is changed by adjusting the voltage, and the reaction results corresponding to different input powers are shown in Table 2.

[0030] Table 2 Reaction results corresponding to different input powers

[0031] It can be seen from Table 2 that the increase of plasma input power can improve the conversion rate of hydrogen sulfide and carbon dioxide, and reduce the molar ratio of hydrogen to carbon monoxide in the product, and the input power of 180W is optimal.

[0032] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solutions of the present invention may be modified or replaced by equivalents without departing from the spirit and scope of the technical solutions of the present invention, which should all be included in the scope of the claims of the present invention.

Claims

1. A method for preparing a zirconium oxide catalyst, characterized in that: The method comprises the following steps: (1) dissolving a zirconium source and a complexing agent in water, wherein the zirconium ion concentration in the obtained solution is 0.05-0.5 mol / L, and the molar ratio of the complexing agent to the zirconium salt is (0.5-5):1; (2) adjusting the pH to 6-9, and reflux with stirring at 90-110°C for 10-12 hours; (3) adding ammonium bicarbonate and transferring the resulting solution to a crystallization kettle for crystallization for 24 to 48 hours; (4) filtering, washing, drying and grinding the product obtained in step (3) into powder, placing the powder into a dielectric barrier discharge plasma device at a discharge power of 80 to 100 W for 3 to 8 hours; (5) calcining the product obtained in step (4) to obtain a zirconium oxide catalyst; The complexing agent is one or more of diethanolamine, triethanolamine, ethylenediaminetetraacetate, diethylenetriaminepentacarboxylate, citric acid, and tartaric acid; The zirconium salt includes one of zirconium oxychloride, zirconium nitrate or zirconium oxynitrate.

2. The method for preparing a zirconium oxide catalyst according to claim 1, characterized in that: Step (2) further comprises adjusting the pH to 6-9 and then adding a dispersant, wherein the dispersant is one or more of cetyltrimethylammonium bromide, polyethylene glycol, sodium dodecylbenzene sulfonate, and polyvinyl pyrrolidone.

3. The method for preparing a zirconium oxide catalyst according to claim 2, characterized in that: In step (2), the concentration of the dispersant is 0.1wt%-5wt%.

4. The method for preparing a zirconium oxide catalyst according to claim 1 or 2, characterized in that: The crystallization temperature is 140-180°C.

5. The method for preparing a zirconium oxide catalyst according to claim 1 or 2, characterized in that: In step (4), the powder is placed in a dielectric barrier discharge plasma device and hydrogen is introduced at a rate of 10 to 20 ml / min to perform dielectric barrier discharge.

6. The method for preparing a zirconium oxide catalyst according to claim 1 or 2, characterized in that: In step (5), the calcination temperature is 400-900° C. and the calcination time is 3-8 hours.

7. Use of the catalyst prepared by the method for preparing the zirconium oxide catalyst according to claim 1 in catalyzing the co-production of hydrogen and carbon monoxide from carbon dioxide and hydrogen sulfide.

8. The use according to claim 7, characterized in that: In an inert atmosphere, carbon dioxide and hydrogen sulfide gas are introduced, and a plasma device is turned on for reaction. The discharge power of the plasma device is 120-180W and the frequency is 10-30 kHz.

9. The use according to claim 8, characterized in that: The inert atmosphere includes nitrogen, the volume percentage of hydrogen sulfide in the reaction gas is 34%-49%, the volume percentage of carbon dioxide is 1%-16%; the volume percentage of nitrogen is 40-50%; the reaction temperature is 120℃-350℃, the space velocity is 100-2000h -1 , the reaction pressure is 0.1-0.3MPa.

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