A catalytic material for deeply removing trace carbon monoxide from hydrogen and a preparation method thereof

Abstract

A catalytic material for deeply removing trace carbon monoxide from hydrogen and a preparation method thereof, belonging to the technical field of catalysts. The preparation method of the catalytic material for deeply removing trace carbon monoxide from hydrogen includes four steps: preparing a copper strontium tannate complex, preparing a copper strontium doped zirconium phosphate powder, preparing a boron modified copper strontium doped zirconium phosphate powder, and oxidative calcination. The catalytic material for deeply removing trace carbon monoxide from hydrogen obtained in the present invention has an effective reaction temperature range for removing CO of 50~185°C, and can remove carbon monoxide with a mass concentration of 100~106 ppm in a hydrogen-rich feed gas to a mass concentration of 10~30 ppb of carbon monoxide in the product gas.

Description

Technical Field

[0001] The present invention relates to a catalytic material for deeply removing trace carbon monoxide in hydrogen and a preparation method thereof, belonging to the technical field of catalysts. Background Art

[0002] With the development of the chemical industry, hydrogen has become an important chemical synthesis raw material and clean secondary energy source. Industrial hydrogen can be obtained by various methods, such as electrolysis, water gas shift method, hydrocarbon cracking method, and hydrocarbon steam reforming method, etc. However, a certain amount of carbon oxides are contained in most of the raw hydrogen produced. After carbon monoxide shift and decarbonization treatment, a small amount of carbon monoxide still remains. Even trace amounts can affect the quality of hydrogen and cause a series of serious problems in downstream applications, such as catalyst poisoning in hydrogenation synthesis reactions, electrode poisoning in hydrogen fuel cells, poisoning of iron melting catalysts in the synthetic ammonia industry. For another example, high-purity hydrogen with a carbon monoxide content lower than several ppb levels is required in the electronics industry, and the carbon monoxide content in polymerization-grade olefin raw materials does not exceed 30 ppb, etc. Therefore, it is necessary to deeply and thoroughly remove trace carbon monoxide in hydrogen.

[0003] Common methods for carbon monoxide removal mainly include adsorption method, Pd membrane separation method, carbon monoxide methanation method, and carbon monoxide selective oxidation method. The adsorption method has limited capacity and large equipment volume. The Pd membrane separation method has high cost and high operating temperature (350 - 500 °C). The carbon monoxide methanation method consumes 3 mol of hydrogen while removing 1 mol of carbon monoxide. Relatively speaking, the carbon monoxide selective oxidation method is the most economical and effective method for removing trace carbon monoxide in hydrogen.

[0004] The carbon monoxide selective oxidation method mainly relies on catalysts for the oxidative removal of carbon monoxide. Currently, catalysts used for carbon monoxide catalytic oxidation mainly include supported noble metal (Pt, Pd, Au) catalysts and transition metal oxide (CuO, Co3O4) catalysts, etc. Although noble metal oxidants have high activity, due to defects such as limited reserves, high cost, and poor stability of noble metals, developing non-noble metal catalysts with excellent low-temperature activity, good thermal stability, and high conversion rate has become a common consensus in the industry.

[0005] Chinese Patent CN117443399A discloses a catalyst for removing trace carbon monoxide from hydrogen-rich gas, its preparation method and application. Using metal precursors, surfactants, and precipitants as raw materials, a special morphology catalyst is prepared by controlling the reaction kinetics through hydrothermal method, and each component is evenly dispersed to form a stable structure. During the calcination process, the metal precursor salt is converted into a metal oxide active component, so that the finally prepared catalyst can be directly used for removing trace carbon monoxide from hydrogen-rich gas, simplifying the hydrogen purification process. For the catalyst for removing trace carbon monoxide from hydrogen-rich gas obtained in this invention, the carbon monoxide conversion rate at 125°C can only reach 90.28%. It can be seen that the activity at low temperature is not very good. When the carbon monoxide conversion rate reaches more than 99%, a high temperature of 175°C is required. Therefore, the catalyst prepared in this patent can only show high activity and very high conversion rate at a relatively high temperature.

[0006] Chinese Patent CN102921431A discloses a catalyst for oxidative removal of carbon monoxide in hydrogen and its preparation method. The catalyst is a carrier loaded with active components and promoters; the active component is Pt, and the promoters are one or a combination of two of Zn, Cu, La, Ce, Pr, Fe, Sn, and Co; the loading amount of the active component is 0.01 - 0.1 wt% of the catalyst, and the loading amount of the promoter is 0.5 - 5 wt% of the catalyst. For the catalyst prepared in this patent, the active component is the noble metal platinum, with a high cost, and the low-temperature activity is not ideal. A temperature above 100°C is required to achieve a carbon monoxide mass concentration below 1 ppm after treatment.

[0007] As can be seen above, for the catalyst materials used to remove trace carbon monoxide from hydrogen, there are still significant problems such as poor low-temperature activity, low carbon monoxide conversion rate at low temperature, and high-cost noble metals. Therefore, developing a catalytic material with high low-temperature activity, high carbon monoxide conversion rate at low temperature, and no use of noble metals for deep removal of trace carbon monoxide from hydrogen is of great significance and urgent practical need for improving the quality of hydrogen. Summary of the Invention

[0008] Aiming at the deficiencies of the above-mentioned existing technologies, the present invention provides a catalytic material for deep removal of trace carbon monoxide from hydrogen and its preparation method, achieving the following invention objectives: preparing a catalytic material with high low-temperature activity, high carbon monoxide conversion rate at low temperature, and no use of noble metals for deep removal of trace carbon monoxide from hydrogen.

[0009] To achieve the above invention objectives, the present invention adopts the following technical solutions:

[0010] A catalytic material for deep removal of trace carbon monoxide in hydrogen and a preparation method thereof. The catalytic material for deep removal of trace carbon monoxide in hydrogen has an effective reaction temperature range for CO removal of 50 - 185 °C, and can remove carbon monoxide with a mass concentration of 100 - 106 ppm in a hydrogen-rich feed gas to a mass concentration of 10 - 30 ppb in the product gas.

[0011] The preparation method of the catalytic material for deep removal of trace carbon monoxide in hydrogen includes four steps: preparing a copper strontium tannate complex, preparing a copper strontium doped zirconium phosphate powder, preparing a boron modified copper strontium doped zirconium phosphate powder, and oxidative calcination.

[0012] The following is a further improvement of the above technical solution:

[0013] Step 1: Prepare a copper strontium tannate complex

[0014] After dissolving a water-soluble copper salt, a water-soluble strontium salt, and deionized water into a solution, tannic acid is added. After stirring and dissolving completely, it is left to stand for complexation. After the complexation is completed, acetonitrile is added. After stirring to precipitate, it is filtered, and the filtered solid is dried at a low temperature to obtain a copper strontium tannate complex.

[0015] The water-soluble copper salt is one of copper chloride, copper sulfate, copper nitrate, and copper acetate, a mixture composed of any two in any mass ratio, or a mixture composed of any two or more in any mass ratio.

[0016] The water-soluble strontium salt is one of strontium chloride, strontium nitrate, and strontium acetate, a mixture composed of any two in any mass ratio, or a mixture composed of the three in any mass ratio.

[0017] The mass ratio of the water-soluble copper salt, the water-soluble strontium salt, deionized water, tannic acid, and acetonitrile is 10 - 40:13 - 50:100 - 240:20 - 65:80 - 180.

[0018] For the standing complexation, the standing time is 15 - 25 hours.

[0019] For the low-temperature drying, the drying temperature is 50 - 65 °C, and the drying time is 20 - 30 hours.

[0020] Step 2: Prepare a copper strontium doped zirconium phosphate powder

[0021] Zirconium oxychloride, a copper strontium tannate complex, and deionized water are added to a mixing kettle. After stirring and dissolving completely, water-soluble phosphosilicate is added. After fully stirring evenly at room temperature, the obtained mixed solution is transferred to a stainless steel reaction kettle with a polytetrafluoroethylene lining. Under closed conditions, it is heated to a crystallization temperature and kept constant. After complete constant-temperature crystallization, it is filtered, washed, and dried to obtain a copper strontium doped zirconium phosphate powder.

[0022] The mass ratio of the zirconium oxychloride, copper strontium tannate complex, deionized water, and water-soluble phosphosilicate is 25-55:8-15:110-220:15-40;

[0023] The crystallization temperature is 120-180 °C;

[0024] For the isothermal crystallization, the crystallization time is 48-70 hours;

[0025] For the washing, wash with deionized water until the pH value of the wash liquor is neutral;

[0026] For the drying, the drying temperature is 70-95 °C and the drying time is 40-65 hours.

[0027] Step 3, Prepare boron-modified copper strontium-doped zirconium phosphate powder

[0028] Add the copper strontium-doped zirconium phosphate powder and toluene into a dispersion kettle. After strong dispersion and uniformity, reduce to a low dispersion rate, then heat up and keep at a constant temperature to the reaction temperature. While maintaining the condensing reflux state, add a silane coupling agent containing an isocyanate group. After the reaction is complete, add a borate ester, then add deionized water, and continue the constant temperature reaction until the borate ester reaction is complete. Then, perform centrifugal separation. The separated solid is washed and dried to obtain boron-modified copper strontium-doped zirconium phosphate powder;

[0029] The silane coupling agent containing an isocyanate group is one or a mixture of two of 3-isocyanatopropyltrimethoxysilane and 3-isocyanatopropyltriethoxysilane in any mass ratio;

[0030] The borate ester is one of trimethyl borate, triethyl borate, and tributyl borate, a mixture of any two in any mass ratio, or a mixture of all three in any mass ratio;

[0031] The mass ratio of the copper strontium-doped zirconium phosphate powder, toluene, silane coupling agent containing an isocyanate group, borate ester, and deionized water is 25-60:150-340:8-15:10-25:0.5-1.3;

[0032] For the strong dispersion, the dispersion rate is 8000-13000 revolutions per minute;

[0033] For the low dispersion rate, the dispersion rate is 1000-2000 revolutions per minute;

[0034] The reaction temperature is 70-90 °C;

[0035] After the reaction is complete, the reaction time is 3-6 hours;

[0036] After the reaction until the borate ester reaction is complete, the reaction time is 5-9 hours;

[0037] For the washing, it is washed with absolute ethanol 3 - 5 times, and the amount of absolute ethanol used each time is equal to the mass of the solid to be washed;

[0038] For the drying, the drying temperature is 50 - 80 °C and the drying time is 9 - 15 hours.

[0039] Step 4: Oxidative roasting

[0040] Put the boron - modified copper - strontium - doped zirconium phosphate powder into a muffle furnace. After heating up and keeping the temperature constant at the roasting temperature, conduct constant - temperature roasting. After the roasting is completed, cool it down to room temperature to obtain a catalytic material for deeply removing trace carbon monoxide in hydrogen;

[0041] For the heating up and keeping the temperature constant at the roasting temperature, the heating rate is 1 - 3 °C / min and the roasting temperature is 500 - 600 °C;

[0042] For the constant - temperature roasting, the roasting time is 1 - 4 hours.

[0043] Compared with the prior art, the present invention has the following beneficial effects:

[0044] 1. The present invention uses water - soluble phosphosilicate as the phosphorus source and zirconium oxychloride as the zirconium source, and synthesizes zirconium phosphate powder by the hydrothermal method. During the synthesis process, a copper - strontium - tannic acid complex is added, introducing two elements, copper and strontium, into the zirconium phosphate powder. After oxidative roasting, when the two elements, copper and strontium, become metal oxides, they possess very excellent carbon monoxide catalytic removal performance. The zirconium phosphate powder is a layered porous compound with very good thermal stability and a very large specific surface area. Using it as the carrier of copper - strontium oxide can not only provide a huge catalytic reaction site, but also ensure the thermal stability and resistance to gas flow erosion of the carrier itself and copper - strontium oxide. Moreover, during the oxidative roasting process, a certain chemical bonding will be generated between the copper - strontium oxide and the zirconium phosphate carrier through high - temperature reaction, which maximally improves the binding force between the copper - strontium oxide and the zirconium phosphate carrier, enabling the copper - strontium oxide to firmly adhere to the surface of the zirconium phosphate powder. Therefore, the catalytic material obtained by the present invention will have excellent and lasting catalytic efficacy;

[0045] 2. To promote the uniform dispersion of copper and strontium metal elements on zirconium phosphate powder, the characteristics of tannic acid to complex and adsorb metal ions were first used to prepare a copper-strontium tannic acid complex. Through the uniform complexation and adsorption of tannic acid, the rates of copper and strontium metal ions entering the layered structure of zirconium phosphate crystals during the hydrothermal synthesis process were controlled, avoiding the excessive adsorption of zirconium phosphate on single copper ions or strontium ions due to the different magnitudes of the charge effects inside the layered structure of zirconium phosphate, thereby causing a huge difference in the adsorption amounts of the two metal ions. Eventually, due to the very uneven distribution or dispersion of copper and strontium ions on the surface of zirconium phosphate, the catalytic performance decreased significantly.

[0046] 3. In the process of designing the boron-modified copper-strontium-doped zirconium phosphate powder of the present invention, the specific reaction process is roughly as follows: First, the active hydroxyl groups on the inner and outer surfaces of zirconium phosphate powder react with a silane coupling agent containing isocyanate groups. After the reaction is complete, the inner and outer surfaces of zirconium phosphate powder are covered with isocyanate groups and siloxane groups. Then, borate ester and a very small amount of water are added. The boric acid generated by the hydrolysis of borate ester reacts with isocyanate groups and siloxane groups. After the reaction is complete, the inner and outer surfaces of zirconium phosphate powder will be covered with borate radicals. In this way, during the subsequent oxidation roasting process, boron forms some ionic compounds or covalent compounds with copper, strontium, or zirconium elements, which will improve the catalytic activity of the two catalytic elements of copper and strontium, and thus also reduce the reaction temperature range for effectively removing CO.

[0047] 4. The catalytic material obtained in the present invention for deeply removing trace carbon monoxide in hydrogen has a reaction temperature range for effectively removing CO of 50 - 185 °C, and can remove carbon monoxide with a mass concentration of 100 - 106 ppm in a hydrogen-rich raw material gas to a mass concentration of 10 - 30 ppb of carbon monoxide in the product gas. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1 It is a scanning electron microscope photograph with a 5000-fold magnification of the surface of the catalytic material obtained in Example 1 for deeply removing trace carbon monoxide in hydrogen, after being tableted and sieved to obtain particles between 40 - 60 mesh.

[0049] Figure 2 It is a scanning electron microscope photograph with a 100000-fold magnification of the surface of the catalytic material obtained in Example 1 for deeply removing trace carbon monoxide in hydrogen, after being tableted and sieved to obtain particles between 40 - 60 mesh. DETAILED DESCRIPTION OF THE INVENTION

[0050] The following are the preferred embodiments of the present invention. It should be understood that the preferred embodiments described herein are only for the purpose of illustrating and explaining the present invention, and are not used to limit the present invention.

[0051] Example 1: A preparation method of a catalytic material for deeply removing trace carbon monoxide in hydrogen

[0052] Step 1: Prepare copper strontium tannate complex

[0053] After mixing and dissolving water-soluble copper salt, water-soluble strontium salt, and deionized water into a solution, add tannic acid. After stirring vigorously until completely dissolved, let it stand for complexation. After the complexation is completed, add acetonitrile. After stirring to precipitate, filter. The solid filtered out is dried at low temperature to obtain copper strontium tannate complex;

[0054] The water-soluble copper salt is copper chloride;

[0055] The water-soluble strontium salt is strontium chloride;

[0056] The mass ratio of the water-soluble copper salt, water-soluble strontium salt, deionized water, tannic acid, and acetonitrile is 30:40:200:50:150;

[0057] For the standing complexation, the standing time is 23 hours;

[0058] For the low-temperature drying, the drying temperature is 60 °C and the drying time is 26 hours.

[0059] Step 2: Prepare copper strontium-doped zirconium phosphate powder

[0060] Add zirconium oxychloride, copper strontium tannate complex, and deionized water into a mixing kettle. After stirring until completely dissolved, add water-soluble phosphosilicate. After stirring evenly at room temperature, transfer the obtained mixed solution to a stainless steel autoclave with a polytetrafluoroethylene liner. Under closed conditions, heat up and keep it at the crystallization temperature. After complete constant-temperature crystallization, obtain copper strontium-doped zirconium phosphate powder after filtration, washing, and drying;

[0061] The mass ratio of zirconium oxychloride, copper strontium tannate complex, deionized water, and water-soluble phosphosilicate is 45:11:180:30;

[0062] The crystallization temperature is 160 °C;

[0063] For the constant-temperature crystallization, the crystallization time is 60 hours;

[0064] For the washing, wash with deionized water until the pH value of the washing liquid is neutral;

[0065] For the drying, the drying temperature is 80 °C and the drying time is 55 hours.

[0066] Step 3: Prepare boron-modified copper strontium-doped zirconium phosphate powder

[0067] Put the copper strontium doped zirconium phosphate powder and toluene into a dispersion kettle. After strong dispersion and uniformity, reduce the dispersion rate to a low level. Then, raise the temperature and keep it constant at the reaction temperature. While maintaining the condensing reflux state, add a silane coupling agent containing an isocyanate group. After the reaction is complete, add a borate ester. Then, add deionized water and continue the constant-temperature reaction until the borate ester reaction is complete. After centrifugal separation, the separated solid is washed and dried to obtain the boron-modified copper strontium doped zirconium phosphate powder.

[0068] The silane coupling agent containing an isocyanate group is 3-isocyanatopropyltrimethoxysilane.

[0069] The borate ester is trimethyl borate.

[0070] The mass ratio of the copper strontium doped zirconium phosphate powder, toluene, the silane coupling agent containing an isocyanate group, the borate ester, and deionized water is 45:300:11:20:1.

[0071] For the strong dispersion, the dispersion rate is 12,000 revolutions per minute.

[0072] For the low dispersion rate, the dispersion rate is 1,600 revolutions per minute.

[0073] The reaction temperature is 85 °C.

[0074] After the reaction is complete, the reaction time is 5 hours.

[0075] After the reaction until the borate ester reaction is complete, the reaction time is 8 hours.

[0076] For the washing, wash 4 times with absolute ethanol, and the amount of absolute ethanol used each time is equal to the mass of the solid to be washed.

[0077] For the drying, the drying temperature is 60 °C and the drying time is 11 hours.

[0078] Step 4: Oxidative roasting

[0079] Put the boron-modified copper strontium doped zirconium phosphate powder into a muffle furnace. After raising the temperature and keeping it constant at the roasting temperature, conduct constant-temperature roasting. After the roasting is completed, cool it to room temperature to obtain a catalytic material for deeply removing trace carbon monoxide in hydrogen.

[0080] For raising the temperature and keeping it constant at the roasting temperature, the heating rate is 2 °C / min and the roasting temperature is 560 °C.

[0081] For the constant-temperature roasting, the roasting time is 3 hours.

[0082] Example 2: A preparation method of a catalytic material for deeply removing trace carbon monoxide in hydrogen

[0083] Step 1: Prepare tannic acid copper strontium complex

[0084] After the water-soluble copper salt, water-soluble strontium salt, and deionized water are mixed and dissolved into a solution, tannic acid is added. After being vigorously stirred and completely dissolved, it is left to stand for complexation. After the complexation is completed, acetonitrile is added. After stirring to precipitate a solid, it is filtered. The filtered solid is dried at a low temperature to obtain a copper strontium tannate complex;

[0085] The water-soluble copper salt is copper sulfate;

[0086] The water-soluble strontium salt is strontium nitrate;

[0087] The mass ratio of the water-soluble copper salt, water-soluble strontium salt, deionized water, tannic acid, and acetonitrile is 10:13:100:20:80;

[0088] For the standing complexation, the standing time is 15 hours;

[0089] For the low-temperature drying, the drying temperature is 50 °C and the drying time is 20 hours.

[0090] Step 2: Prepare copper strontium-doped zirconium phosphate powder

[0091] Zirconium oxychloride, copper strontium tannate complex, and deionized water are added to a mixing kettle. After being stirred and completely dissolved, water-soluble phosphosilicate is added. After being fully stirred evenly at room temperature, the obtained mixed solution is transferred to a stainless steel reaction kettle with a polytetrafluoroethylene lining. Under closed conditions, it is heated to a crystallization temperature and kept at a constant temperature. After complete constant-temperature crystallization, it is filtered, washed, and dried to obtain copper strontium-doped zirconium phosphate powder;

[0092] The mass ratio of zirconium oxychloride, copper strontium tannate complex, deionized water, and water-soluble phosphosilicate is 25:8:110:15;

[0093] The crystallization temperature is 120 °C;

[0094] For the constant-temperature crystallization, the crystallization time is 48 hours;

[0095] For the washing, it is washed with deionized water until the pH value of the wash liquor is neutral;

[0096] For the drying, the drying temperature is 70 °C and the drying time is 40 hours.

[0097] Step 3: Prepare boron-modified copper strontium-doped zirconium phosphate powder

[0098] Add copper strontium doped zirconium phosphate powder and toluene into a dispersion kettle. After strong dispersion to uniformity, reduce to a low dispersion rate, then raise the temperature and keep it constant at the reaction temperature. While maintaining the condensation reflux state, add a silane coupling agent containing an isocyanate group. After the reaction is complete, add boric acid ester, then add deionized water, and continue to react at a constant temperature until the boric acid ester reaction is complete. Then perform centrifugal separation. The separated solid is washed and dried to obtain boron-modified copper strontium doped zirconium phosphate powder;

[0099] The silane coupling agent containing an isocyanate group is 3-isocyanatopropyltriethoxysilane;

[0100] The boric acid ester is triethyl borate;

[0101] The mass ratio of the copper strontium doped zirconium phosphate powder, toluene, the silane coupling agent containing an isocyanate group, boric acid ester, and deionized water is 25:150:8:10:0.5;

[0102] For the strong dispersion, the dispersion rate is 8000 revolutions per minute;

[0103] For the low dispersion rate, the dispersion rate is 1000 revolutions per minute;

[0104] The reaction temperature is 70 °C;

[0105] After the reaction is complete, the reaction time is 3 hours;

[0106] After the reaction until the boric acid ester reaction is complete, the reaction time is 5 hours;

[0107] For the washing, wash with absolute ethanol 3 times, and the amount of absolute ethanol used each time is equal to the mass of the solid being washed;

[0108] For the drying, the drying temperature is 50 °C and the drying time is 9 hours.

[0109] Step 4, Oxidative roasting

[0110] Put the boron-modified copper strontium doped zirconium phosphate powder into a muffle furnace. After raising the temperature and keeping it constant at the roasting temperature, perform constant-temperature roasting. After the roasting is completed, cool to room temperature to obtain a catalytic material for deeply removing trace carbon monoxide in hydrogen;

[0111] For raising the temperature and keeping it constant at the roasting temperature, the heating rate is 1 °C / min and the roasting temperature is 500 °C;

[0112] For the constant-temperature roasting, the roasting time is 1 hour.

[0113] Example 3: A preparation method of a catalytic material for deeply removing trace carbon monoxide in hydrogen

[0114] Step 1, Prepare tannic acid copper strontium complex

[0115] After a water-soluble copper salt, a water-soluble strontium salt and deionized water are mixed and dissolved into a solution, tannic acid is added, and after strong stirring to completely dissolve, the solution is allowed to stand for complexation. After the complexation is completed, acetonitrile is added, and after stirring to precipitate, the solution is filtered, and the filtered solid is dried at low temperature to obtain a tannic acid copper strontium complex;

[0116] The water-soluble copper salt is copper nitrate;

[0117] The water-soluble strontium salt is strontium acetate;

[0118] The mass ratio of the water-soluble copper salt, the water-soluble strontium salt, deionized water, tannic acid and acetonitrile is 40:50:240:65:180;

[0119] The static complexation has a static time of 25 hours;

[0120] The low-temperature drying has a drying temperature of 65° C. and a drying time of 30 hours.

[0121] Step 2: Preparation of copper-strontium-doped zirconium phosphate powder

[0122] Zirconium oxychloride, copper strontium tannate complex and deionized water are added to a mixing kettle, stirred and dissolved completely, and then water-soluble silicon phosphate is added. After being fully stirred at room temperature, the obtained mixed solution is transferred to a stainless steel reactor with a polytetrafluoroethylene liner, and the temperature is raised to the crystallization temperature under a closed condition. After the constant temperature crystallization is complete, the copper strontium doped zirconium phosphate powder is obtained after filtering, washing and drying;

[0123] The mass ratio of the zirconium oxychloride, copper strontium tannate complex, deionized water, and water-soluble silicon phosphate is 55:15:220:40;

[0124] The crystallization temperature is 180°C;

[0125] The constant temperature crystallization, the crystallization time is 70 hours;

[0126] The washing comprises washing with deionized water until the pH value of the washing solution is neutral;

[0127] The drying temperature is 95° C. and the drying time is 65 hours.

[0128] Step 3: Preparation of boron-modified copper-strontium-doped zirconium phosphate powder

[0129] Add copper strontium doped zirconium phosphate powder and toluene into a dispersion kettle. After strong dispersion until homogeneous, reduce to a low dispersion rate, then heat up and keep at a constant temperature to the reaction temperature. While maintaining the condensing reflux state, add a silane coupling agent containing an isocyanate group. After the reaction is complete, add borate ester, then add deionized water, and continue to react at a constant temperature until the borate ester reaction is complete. Then perform centrifugal separation. The separated solid is washed and dried to obtain boron-modified copper strontium doped zirconium phosphate powder;

[0130] The silane coupling agent containing an isocyanate group is 3-isocyanatopropyltrimethoxysilane;

[0131] The borate ester is tributyl borate;

[0132] The mass ratio of the copper strontium doped zirconium phosphate powder, toluene, the silane coupling agent containing an isocyanate group, borate ester, and deionized water is 60:340:15:25:1.3;

[0133] For the strong dispersion, the dispersion rate is 13,000 revolutions per minute;

[0134] For the low dispersion rate, the dispersion rate is 2,000 revolutions per minute;

[0135] The reaction temperature is 90 °C;

[0136] After the reaction is complete, the reaction time is 6 hours;

[0137] After the reaction until the borate ester reaction is complete, the reaction time is 9 hours;

[0138] For the washing, wash 5 times with absolute ethanol, and the amount of absolute ethanol used each time is equal to the mass of the solid being washed;

[0139] For the drying, the drying temperature is 80 °C and the drying time is 15 hours.

[0140] Step 4, Oxidative roasting

[0141] Put the boron-modified copper strontium doped zirconium phosphate powder into a muffle furnace. After heating up and keeping at a constant temperature to the roasting temperature, perform constant-temperature roasting. After the roasting is completed, cool down to room temperature to obtain a catalytic material for deeply removing trace carbon monoxide in hydrogen;

[0142] For heating up and keeping at a constant temperature to the roasting temperature, the heating rate is 3 °C / min and the roasting temperature is 600 °C;

[0143] For the constant-temperature roasting, the roasting time is 4 hours.

[0144] Example 4: A preparation method of a catalytic material for deeply removing trace carbon monoxide in hydrogen

[0145] Step 1, Prepare tannic acid copper strontium complex

[0146] The water-soluble copper salt is copper acetate, and other operations are the same as those in Example 1;

[0147] The operations in Steps 2, 3, and 4 are the same as those in Example 1.

[0148] Comparative Example 1: On the basis of Example 1, in Step 1 of preparing the strontium copper tannate complex and in Step 2 of preparing the copper strontium-doped zirconium phosphate powder, 11 parts of the strontium copper tannate complex are replaced with 11 parts of tannic acid in equal amounts. The specific operations are as follows:

[0149] Do not perform Step 1 of preparing the strontium copper tannate complex;

[0150] Step 2: Prepare the copper strontium-doped zirconium phosphate powder

[0151] Replace 11 parts of the strontium copper tannate complex with 11 parts of tannic acid in equal amounts, and other operations are the same as those in Example 1;

[0152] The operations in Steps 3 and 4 are the same as those in Example 1.

[0153] Comparative Example 2: On the basis of Example 1, in Step 1 of preparing the strontium copper tannate complex and in Step 2 of preparing the copper strontium-doped zirconium phosphate powder, 11 parts of the strontium copper tannate complex are replaced with a mixture of 11 parts of a water-soluble copper salt and a water-soluble strontium salt, and the mass ratio of the water-soluble copper salt to the water-soluble strontium salt is 30:40. The specific operations are as follows:

[0154] Do not perform Step 1 of preparing the strontium copper tannate complex;

[0155] Step 2: Prepare the copper strontium-doped zirconium phosphate powder

[0156] Replace 11 parts of the strontium copper tannate complex with a mixture of 11 parts of a water-soluble copper salt and a water-soluble strontium salt, and the mass ratio of the water-soluble copper salt to the water-soluble strontium salt is 30:40. Other operations are the same as those in Example 1;

[0157] The operations in Steps 3 and 4 are the same as those in Example 1.

[0158] Comparative Example 3: On the basis of Example 1, do not perform Step 3 of preparing the boron-modified copper strontium-doped zirconium phosphate powder, and directly perform oxidative roasting on the copper strontium-doped zirconium phosphate powder obtained in Step 2. The specific operations are as follows:

[0159] The operations in Steps 1 and 2 are the same as those in Example 1;

[0160] Do not perform Step 3 of preparing the boron-modified copper strontium-doped zirconium phosphate powder;

[0161] Step 4: Oxidative roasting

[0162] Put the copper strontium-doped zirconium phosphate powder into a muffle furnace, and the roasting process is the same as that in Example 1.

[0163] Performance test:

[0164] The catalytic materials for deep removal of trace carbon monoxide from hydrogen obtained in Examples 1, 2, 3, 4 and Comparative Examples 1, 2, 3 were tableted and sieved. Granular samples between 40 and 60 meshes were taken and the reaction evaluation of the CO oxidation removal performance in a hydrogen-rich atmosphere was carried out on a fixed-bed reactor. The sample loading amount was 1 mL, the inner diameter of the reactor was 8 mm, the loading height was 30 mm, the reaction heating rate was 2.5 °C / min, and the test temperature range was 40 - 250 °C. The sample was first reduced in a 10 vol% H2 / N2 atmosphere at 200 °C for 1 h, and then the performance test was carried out. The performance test conditions were: the total gas flow rate was 50 mL / min, and the gas mass space velocity was 20000 mL·gcat -1 · h -1 . The detection of the CO mass concentration in the raw material gas and the product gas was carried out using a TR3000 type micro carbon monoxide analyzer of AMETEK Company. The detection lower limit of this instrument was 10 ppb, the resolution was 0.1 ppb. In the reaction temperature range of 40 - 250 °C, when the CO mass concentration in the product gas was less than 100 ppb, it was considered that carbon monoxide was effectively removed;

[0165] The test results are shown in Table 1:

[0166] Table 1

[0167] Effective CO removal reaction temperature range, °C CO mass concentration in the feed gas, ppm CO mass concentration in the product gas, ppb Example 1 53~180 100 11~23 Example 2 50~175 104 10~26 Example 3 54~185 102 14~30 Example 4 50~180 106 13~27 Comparative Example 1 Failed to effectively remove 106 93206~99507 Comparative Example 2 175~235 101 85~98 Comparative Example 3 95~240 106 64~96

[0168] As can be seen from the test data in Table 1, Examples 1-4 can remove about 100 ppm of carbon monoxide in the hydrogen-rich gas to below 30 ppb in the range of 50~185°C. This shows that the catalytic material for deep removal of trace carbon monoxide in hydrogen obtained in the embodiments of the present invention can deeply remove trace carbon monoxide in the hydrogen-rich gas at a low temperature of 50°C, and the temperature range for maintaining the catalytic activity is relatively wide, and high activity can also be maintained at about 180°C, which also shows that the obtained catalytic material of the present invention has very good high-temperature resistance; in Comparative Example 1, copper strontium tannate complex is not prepared, that is, the final catalytic material does not contain two metal elements of copper and strontium. As a result, in Comparative Example 1, in the temperature range of 40~250°C, carbon monoxide cannot be effectively removed, and the mass concentration of CO in the product gas is still close to 100 ppm. This shows that the catalytic material without adding two elements of copper and strontium does not have catalytic performance. It can be seen that the catalytic removal of carbon monoxide is mainly due to the key role played by two metal elements of copper and strontium; in Comparative Example 2, the copper strontium tannate complex is replaced with an equivalent amount of a mixture of water-soluble copper salt and water-soluble strontium salt, that is, the copper salt and strontium salt are not complexed with tannic acid, and the copper salt and strontium salt are directly added during the formation of zirconium phosphate. The reaction temperature range for effectively removing CO in Comparative Example 2 rises to 175~235°C. This may be because the copper strontium tannate complex helps the uniformity of the dispersion of copper and strontium elements during the formation of zirconium phosphate. Due to the complexation of tannic acid, the uniform dispersion of copper and strontium on the zirconium phosphate matrix is promoted, thus greatly increasing the active area of the catalyst; in Comparative Example 3, without boron modification, the reaction temperature range for effectively removing CO in Comparative Example 3 also rises to 95~240°C. It may be because after boron doping modification, boron forms some ionic compounds or covalent compounds with copper and strontium or boron and zirconium elements, which greatly improves the catalytic activity of the two catalytic elements of copper and strontium, and thus reduces the reaction temperature range for effectively removing CO.

[0169] Appendix Figure 1 and Appendix Figure 2 are respectively the scanning electron microscope photos of the catalytic material for deep removal of trace carbon monoxide in hydrogen obtained in Example 1, after being tableted and sieved to obtain particles between 40 and 60 meshes, with a magnification of 5000 times and 100000 times on the surface. Appendix Figure 1 As can be seen from the figure, the particles obtained by tableting are stacked by many flakes. Appendix Figure 2 It can be clearly seen from the figure that the flaky zirconium phosphate with a size of several hundred nanometers is laminated and stacked together.

[0170] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art within the technical scope disclosed by the present invention, according to the technical solution of the present invention and its inventive concept, makes equivalent substitutions or changes, and should be covered by the protection scope of the present invention.

Claims

1. A preparation method of a catalytic material for deeply removing trace carbon monoxide from hydrogen, characterized in that: The preparation method of the catalytic material for deeply removing trace carbon monoxide from hydrogen includes four steps: preparing copper strontium tannate complex, preparing copper strontium doped zirconium phosphate powder, preparing boron modified copper strontium doped zirconium phosphate powder, and oxidative roasting; The method for preparing the copper strontium tannate complex is as follows: after a water-soluble copper salt, a water-soluble strontium salt, and deionized water are mixed and dissolved into a solution, tannic acid is added. After being vigorously stirred and completely dissolved, it is left to stand for complexation. After the complexation is completed, acetonitrile is added. After stirring to precipitate a solid, it is filtered, and the filtered solid is dried at low temperature to obtain the copper strontium tannate complex; The method for preparing the copper strontium doped zirconium phosphate powder is as follows: zirconium oxychloride, copper strontium tannate complex, and deionized water are added to a mixing kettle. After being stirred and completely dissolved, water-soluble phosphosilicate is added. After being fully stirred evenly at room temperature, the obtained mixed solution is transferred to a stainless steel reaction kettle with a polytetrafluoroethylene lining. Under closed conditions, it is heated to a crystallization temperature and kept at a constant temperature. After complete constant temperature crystallization, it is filtered, washed, and dried to obtain the copper strontium doped zirconium phosphate powder; The method for preparing the boron modified copper strontium doped zirconium phosphate powder is as follows: the copper strontium doped zirconium phosphate powder and toluene are added to a dispersion kettle. After being vigorously dispersed evenly, the dispersion rate is reduced, and then it is heated and kept at a constant temperature to the reaction temperature. While maintaining the condensation reflux state, a silane coupling agent containing an isocyanate group is added. After the reaction is complete, borate is added, and then deionized water is added. The reaction is continued at a constant temperature until the borate reaction is complete, and then centrifuged. The separated solid is washed and dried to obtain the boron modified copper strontium doped zirconium phosphate powder.

2. The preparation method of the catalytic material for deeply removing trace carbon monoxide from hydrogen according to claim 1, characterized in that: The method for oxidative roasting is as follows: the boron modified copper strontium doped zirconium phosphate powder is put into a muffle furnace. After being heated and kept at a constant temperature to the roasting temperature, it is roasted at a constant temperature. After the roasting is completed, it is cooled to room temperature to obtain the catalytic material for deeply removing trace carbon monoxide from hydrogen.

3. The preparation method of the catalytic material for deeply removing trace carbon monoxide from hydrogen according to claim 1, characterized in that: The water-soluble copper salt is one of copper chloride, copper sulfate, copper nitrate, copper acetate, or a mixture composed of any two or more of them in any mass ratio; The water-soluble strontium salt is one of strontium chloride, strontium nitrate, strontium acetate, a mixture composed of any two of them in any mass ratio, or a mixture composed of all three of them in any mass ratio; The mass ratio of the water-soluble copper salt, water-soluble strontium salt, deionized water, tannic acid, and acetonitrile is 10 - 40:13 - 50:100 - 240:20 - 65:80 - 180.

4. The preparation method of the catalytic material for deeply removing trace carbon monoxide from hydrogen according to claim 1, characterized in that: The mass ratio of zirconium oxychloride, copper strontium tannate complex, deionized water, and water-soluble phosphosilicate is 25 - 55:8 - 15:110 - 220:15 - 40; The crystallization temperature is 120 - 180 °C; For the constant-temperature crystallization, the crystallization time is 48 to 70 hours.

5. The method for preparing a catalytic material for deeply removing trace carbon monoxide from hydrogen according to claim 1, wherein: The isocyanate group-containing silane coupling agent is one or a mixture of two of 3-isocyanatopropyltrimethoxysilane and 3-isocyanatopropyltriethoxysilane in any mass ratio; The borate ester is one of trimethyl borate, triethyl borate, and tributyl borate, a mixture of any two in any mass ratio, or a mixture of all three in any mass ratio; The mass ratio of the copper strontium-doped zirconium phosphate powder, toluene, the isocyanate group-containing silane coupling agent, the borate ester, and deionized water is 25 to 60: 150 to 340: 8 to 15: 10 to 25: 0.5 to 1.

3.

6. The catalytic material for deeply removing trace carbon monoxide from hydrogen prepared by the preparation method according to any one of claims 1-5, wherein: For the catalytic material for deeply removing trace carbon monoxide from hydrogen, the reaction temperature range for effectively removing CO is 50 to 185 °C, and it can remove carbon monoxide with a mass concentration of 100 to 106 ppm in the hydrogen-rich feed gas to a mass concentration of 10 to 30 ppb of carbon monoxide in the product gas.

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