A platinum-based catalyst regeneration method, regenerated platinum-based catalyst and application thereof

Abstract

The present invention discloses a platinum-based catalyst regeneration method, a regenerated platinum-based catalyst and its application. The platinum-based catalyst regeneration method provided by the present invention adds the platinum-based catalyst to a mixed solution of hydrochloric acid and hydrogen peroxide, so that the platinum sintered on the catalyst after the active component platinum is sintered is converted into chloroplatinic acid, and the chloroplatinic acid can be uniformly and stably loaded on the platinum-based catalyst carrier after removing the water in the solution system, and then after calcination, uniformly dispersed platinum single substance particles are formed, and the particle size of the single substance particles is uniform, which is similar to the size of the platinum single substance particles on the platinum-based catalyst before sintering. Due to the good dispersibility of the active component, the platinum-based catalyst regenerated by the regeneration method provided by the present invention has excellent target reaction selectivity and reactant conversion rate when catalyzing the reaction of dehydrogenating propane to prepare propylene.

Description

Technical Field

[0001] The present invention relates to the technical field of catalyst regeneration, and in particular to a platinum-based catalyst regeneration method, a regenerated platinum-based catalyst and applications thereof. Background Art

[0002] The low-cost propane dehydrogenation method is one of the main methods for producing propylene at present, with high automation, good safety and stability. However, propane dehydrogenation is an endothermic reaction. In order to increase the equilibrium conversion rate of alkanes, the reaction temperature needs to be increased to 500-1000°C. However, high temperature will cause a series of side reactions in the propane dehydrogenation process. In order to solve this problem, it is of great significance to study catalysts that can still maintain high activity and high stability under high temperature conditions.

[0003] Platinum-based catalysts have attracted much attention in the field of propane dehydrogenation due to their high activity in catalyzing propane dehydrogenation reactions. However, platinum-based catalysts have a fatal flaw: during the catalytic propane dehydrogenation process, the high temperature in the reaction system will cause the active component Pt in the platinum-based catalyst to aggregate, form particles and grow. In short, the platinum in the platinum-based catalyst will sinter, and the catalyst will lose its activity. Although it will also cause a reduction in active sites on the catalyst, unlike the temporary deactivation caused by carbon deposition and coking, the Pt sintering caused by high temperature is irreversible for the catalyst, and the activity of the catalyst cannot be restored by itself. Therefore, restoring the activity of the catalyst after Pt sintering is the key to improving the catalytic performance of platinum-based catalysts for propane dehydrogenation reactions.

[0004] The prior art discloses a regeneration method for a platinum-containing low-carbon alkane dehydrogenation catalyst, wherein the halogen on the catalyst is supplemented by introducing a mixed gas containing halogen and water or decomposable oxygen-containing compounds, and then the catalyst is oxidized by introducing an oxygen-containing gas flow. The entire chlorination-oxidation process promotes the redispersion of agglomerated Pt particles in the deactivated catalyst. However, the prior art provides a method for gas-phase regeneration of platinum-based catalysts. In fact, the existing platinum-based catalyst regeneration method is also usually regenerated in the gas phase, because redispersing Pt particles in the gas phase can ensure that the structure of the original active substance of the catalyst is not destroyed. However, regeneration in the gas phase must be treated with chlorine at a high temperature of 300 to 800°C, which greatly increases the energy consumption of the regeneration process. Summary of the invention

[0005] In order to solve the problem in the prior art that a platinum-based catalyst with good dispersion must be regenerated in a gas phase, and thus the regeneration process consumes too much energy, the present invention provides a platinum-based catalyst regeneration method, in which the platinum-based catalyst is regenerated in a liquid phase system composed of hydrochloric acid and hydrogen peroxide, and the original structure of uniformly dispersed platinum particles of the platinum-based catalyst is first destroyed and then rebuilt in the liquid phase, thereby greatly reducing the energy consumption of the regeneration process.

[0006] Another object of the present invention is to provide a regenerated platinum-based catalyst.

[0007] Another object of the present invention is to provide an application of a regenerated platinum-based catalyst in catalyzing propane dehydrogenation.

[0008] The above-mentioned purpose of the present invention is achieved through the following technical solutions:

[0009] A method for regenerating a platinum-based catalyst, wherein the platinum-based catalyst comprises a catalyst carrier and an active component Pt supported on the carrier and sintered, and the method for regenerating the platinum-based catalyst specifically comprises the following steps:

[0010] S1. adding the sintered platinum-based catalyst to a mixed solution of hydrochloric acid and hydrogen peroxide and uniformly dispersing the mixture, and obtaining a regenerated platinum-based catalyst to be activated after sufficient reaction;

[0011] S2. calcining the regenerated platinum-based catalyst to be activated obtained in step S1 to obtain a regenerated platinum-based catalyst;

[0012] In the step S1, the ratio of Pt, hydrochloric acid and hydrogen peroxide on the platinum-based catalyst after Pt sintering is 2 mg: (0.5-2) mL: (0.5-2) mL.

[0013] In a specific embodiment of the present invention, hydrochloric acid is a concentrated hydrochloric acid aqueous solution with a solute mass fraction of 37% conventionally used in the art; hydrogen peroxide is an aqueous solution with a solute mass fraction of 30% conventionally used in the art; and the reaction in step S1 can be carried out at any conventional reaction temperature in the art.

[0014] In step S1, the platinum-based catalyst after Pt sintering is added to a mixed solution of hydrochloric acid and hydrogen peroxide. The Pt on the catalyst can react with the hydrochloric acid and hydrogen peroxide to produce a chemical reaction as shown in the following formula (1):

[0015] 2H2O2+6HCl+Pt=H2PtCl6+4H2O (1)

[0016] It can be seen that under the action of hydrochloric acid and hydrogen peroxide, the Pt metal particles sintered on the catalyst can be converted into chloroplatinic acid that is soluble in water and uniformly dispersed in the entire system. The hydrogen peroxide plays the role of oxidizing Pt, and the chloride ions in the hydrochloric acid can coordinate with the tetravalent platinum ions formed by the oxidation of Pt to form [PtCl6] 2-. However, platinum, as a precious metal with inactive chemical properties, needs to control the ratio of platinum, hydrochloric acid and hydrogen peroxide to 2 mg: (0.5-2) mL: (0.5-2) mL when reacting with hydrogen peroxide and hydrochloric acid. Since the present invention adopts a concentrated hydrochloric acid aqueous solution with a solute mass fraction of 37% and an aqueous solution with a solute mass fraction of 30% conventional in the art, it can be known from the conversion that the molar ratio of platinum to hydrochloric acid and hydrogen peroxide is 1: (582.5-2330): (470.5-1882). It can be seen that a large amount of hydrochloric acid and hydrogen peroxide are needed to treat platinum in order to oxidize platinum and form chloroplatinic acid. However, when the amount of hydrochloric acid and hydrogen peroxide is too large, chloroplatinic acid will be further converted to form other products that are difficult to load on the catalyst carrier, which is also not conducive to the regeneration of the platinum-based catalyst.

[0017] After the sintered Pt on the catalyst is converted into chloroplatinic acid in step S1, the original active material structure of the platinum-based catalyst is completely destroyed, and only the catalyst carrier remains on the solid platinum-based catalyst. In step S1, the platinum-based catalyst is evenly dispersed, and the platinum particles on the catalyst can be fully dissolved to form chloroplatinic acid, but the platinum element will not fall off the catalyst carrier, because the introduction of O and Cl species will lead to the redistribution of electrons around Pt, which may generate [PtOCl] - This type of intermediate product can be firmly adsorbed on the carrier. After the subsequent calcination process, the intermediate product can be converted back into a monodispersed platinum element that is stably adsorbed on the carrier, rebuilding the original active material structure of the platinum-based catalyst, which is the key to the liquid-phase regeneration of the platinum-based catalyst in the present invention.

[0018] The existing method for regenerating platinum-based catalysts needs to be carried out in the gas phase because it is difficult to rebuild the structure of the original active material of the catalyst after destroying it. Specifically, the difficulty lies in achieving the re-loading of the active material platinum on the catalyst. However, after the platinum is converted into chloroplatinic acid in the present invention, [PtOCl] is formed. - etc., so platinum can be reloaded on the catalyst carrier.

[0019] The purpose of step S2 is to fully convert chloroplatinic acid into metal platinum particles. The chloroplatinic acid can be fully converted by fully calcining under conventional calcination conditions in the art.

[0020] Preferably, the calcination temperature in step S2 is 200-800°C.

[0021] Calcination at a temperature above 200°C is beneficial to a more complete conversion of chloroplatinic acid and intermediate products, while calcination at a temperature below 800°C is more conducive to energy saving.

[0022] More preferably, the calcination temperature in step S2 is 500-600°C.

[0023] Preferably, the reaction temperature in step S1 is 50-100°C.

[0024] When the reaction temperature in step S1 is higher than 50°C, the formation reaction of chloroplatinic acid can proceed more fully; but when the reaction temperature is higher than 100°C, it will basically have no effect on the reaction itself, but will increase energy consumption.

[0025] Preferably, the reaction time in step S1 is 1 to 6 hours.

[0026] When the reaction time in step S1 is longer than 1 h, it is beneficial for the chloroplatinic acid generation reaction to proceed fully; however, hydrochloric acid and hydrogen peroxide are both volatile substances. When the reaction time is longer than 6 h, the hydrochloric acid and hydrogen peroxide in the system are easily evaporated and lost.

[0027] More preferably, the reaction time in step S1 is 2 to 4 hours.

[0028] Preferably, the calcination time in step S2 is 1 to 4 hours.

[0029] When the calcination time is longer than 1 h, it is beneficial to the conversion of chloroplatinic acid and intermediates into platinum. When the calcination time is longer than 4 h, the reaction is almost complete, so further increasing the calcination time will result in excessive energy consumption.

[0030] Preferably, the content of Pt in the platinum-based catalyst after Pt sintering in step S1 is 0.1-0.3 wt%.

[0031] More preferably, the content of Pt in the platinum-based catalyst after Pt sintering in step S1 is 0.2 wt %.

[0032] When the Pt content in the platinum-based catalyst is 0.1-0.3wt%, and further 0.2wt%, the low content is more conducive to the regeneration method provided by the present invention to achieve redispersion of the sintered Pt component.

[0033] Preferably, the catalyst carrier in the platinum-based catalyst after Pt sintering in step S1 is a combination of SiO2 and Al2O3.

[0034] Preferably, the mass ratio of SiO2 to Al2O3 in the combination of SiO2 and Al2O3 in step S1 is 1:(1-2).

[0035] When the catalyst carrier in the platinum-based catalyst after Pt sintering is a combination of SiO2 and Al2O3, and further, when the mass ratio of SiO2 to Al2O3 is 1:(1-2), the platinum-based catalyst carrier has a larger specific surface area, which is more conducive to the dispersion of the active component Pt.

[0036] In a specific embodiment of the present invention, 3 wt% of Ga2O3 is also loaded on the platinum-based catalyst after Pt sintering as a dispersing aid. The catalyst is specifically prepared by the following method:

[0037] S01. The potassium chloroplatinate solution and the gallium nitrate solution are fully mixed to obtain a precursor solution;

[0038] S02. The catalyst support is immersed in the precursor solution obtained in step S01, so that the platinum and gallium elements in the precursor solution are fully loaded on the catalyst support, and after the reaction is completed, calcined at 500 to 600°C;

[0039] S03. Calcinate at 800-900° C. to obtain a Pt-sintered platinum-based catalyst.

[0040] The present invention also protects a regenerated platinum-based catalyst prepared by adopting the above-mentioned regeneration method of the platinum-based catalyst.

[0041] The present invention also protects an application of the above regenerated platinum-based catalyst in catalyzing propane dehydrogenation.

[0042] In a specific embodiment of the present invention, when the regenerated platinum-based catalyst is used to catalyze the propane dehydrogenation reaction, the catalyst needs to be pressed into tablets and then sieved to obtain a regenerated platinum-based catalyst with a diameter of 60 to 80 meshes, and then mixed with 60 to 80 mesh quartz sand, and then filled into a reaction device to catalyze the propane dehydrogenation reaction.

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

[0044] The regeneration method of the platinum-based catalyst provided by the present invention can convert the platinum sintered on the catalyst after platinum sintering into uniformly dispersed platinum single-substance particles, and the particle size of the single-substance particles is uniform and similar to the size of the platinum single-substance particles on the platinum-based catalyst before sintering. Due to the good dispersibility of the active component, the platinum-based catalyst regenerated by the regeneration method provided by the present invention has a target reaction selectivity of more than 92.6% and a conversion rate of the reactant propane of more than 63.6% when catalyzing the reaction of dehydrogenating propane to prepare propylene. BRIEF DESCRIPTION OF THE DRAWINGS

[0045] Figure 1 XRD patterns of freshly prepared, Pt-sintered and regenerated platinum-based catalysts according to Example 1 of the present invention.

[0046] Figure 2HAADF-SEM images of (a) freshly prepared, (b) Pt-sintered and (c) regenerated platinum-based catalysts according to Example 1 of the present invention, (d) particle size images of freshly prepared and (f) regenerated platinum-based catalysts according to Example 1 of the present invention, and (e) HRTEM image of the Pt-sintered platinum-based catalyst.

[0047] Figure 3 This is a comparison chart of the catalytic performance of the regenerated platinum-based catalyst obtained in Example 1 of the present invention, the platinum-based catalyst after Pt sintering, and the catalyst before Pt sintering. DETAILED DESCRIPTION

[0048] The present invention is further described below in conjunction with specific embodiments, but the embodiments do not limit the present invention in any form. Unless otherwise specified, the raw materials and reagents used in the embodiments of the present invention are conventionally purchased raw materials and reagents.

[0049] Example 1

[0050] A method for regenerating a platinum-based catalyst, the platinum-based catalyst comprising a catalyst carrier and an active component Pt supported on the carrier and sintered, the content of Pt in the platinum-based catalyst after Pt sintering is 0.2wt%, the catalyst carrier in the platinum-based catalyst after Pt sintering is a combination of SiO2 and Al2O3, wherein the mass ratio of SiO2 to Al2O3 is 1:1.5, and the regeneration method of the platinum-based catalyst specifically comprises the following steps:

[0051] S1. adding the sintered platinum-based catalyst to a mixed solution of hydrochloric acid and hydrogen peroxide and uniformly dispersing the mixture, and reacting the mixture at a reaction temperature of 70° C. for 2 h to obtain a regenerated platinum-based catalyst to be activated;

[0052] S2. calcining the regenerated platinum-based catalyst to be activated obtained in step S1 at 550° C. for 2 to 3 hours to obtain a regenerated platinum-based catalyst;

[0053] In step S1, the ratio of Pt, hydrochloric acid and hydrogen peroxide on the platinum-based catalyst after Pt sintering is 2 mg: 1 mL: 1 mL, wherein the hydrochloric acid is a conventional concentrated hydrochloric acid aqueous solution with a solute mass fraction of 37% in the art; and the hydrogen peroxide is a conventional aqueous solution with a solute mass fraction of 30% in the art.

[0054] Example 2

[0055] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0056] S1. React at a reaction temperature of 50°C for 6 hours.

[0057] Example 3

[0058] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0059] S1. React at a reaction temperature of 100°C for 1 h.

[0060] Example 4

[0061] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0062] S1. React at a reaction temperature of 80°C for 4 hours.

[0063] Example 5

[0064] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0065] S1. The reaction temperature is 35°C.

[0066] Example 6

[0067] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0068] S1. The regenerated platinum-based catalyst to be activated obtained in step S1 is calcined at 400° C. for 3 hours.

[0069] Example 7

[0070] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0071] S1. The regenerated platinum-based catalyst to be activated obtained in step S1 is calcined at 800° C. for 2 h.

[0072] Example 8

[0073] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0074] S2. Calcination is performed at 200°C.

[0075] Example 9

[0076] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0077] S2. Calcination time is 1h.

[0078] Example 10

[0079] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0080] In step S1, the ratio of Pt, hydrochloric acid and hydrogen peroxide on the platinum-based catalyst after Pt sintering is 2 mg: 1.2 mL: 0.5 mL.

[0081] Embodiment 11

[0082] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0083] In step S1, the ratio of Pt, hydrochloric acid and hydrogen peroxide on the platinum-based catalyst after Pt sintering is 2 mg: 0.8 mL: 1.5 mL.

[0084] Comparative Example 1

[0085] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0086] S1. adding the sintered platinum-based catalyst to the hydrochloric acid solution and uniformly dispersing it;

[0087] The ratio of Pt to hydrochloric acid on the platinum-based catalyst after Pt sintering in step S1 is 2 mg:2 mL.

[0088] Comparative Example 2

[0089] A method for regenerating a platinum-based catalyst, which differs from Example 1 in that:

[0090] S1. adding the sintered platinum-based catalyst to the hydrogen peroxide solution and uniformly dispersing it;

[0091] The ratio of Pt to hydrogen peroxide on the platinum-based catalyst after Pt sintering in step S1 is 2 mg:2 mL.

[0092] Performance Testing

[0093] The preparation method of the new catalyst is as follows: a certain amount of potassium chloroplatinate and gallium nitrate hydrate are added to water to prepare a precursor solution, and then a carrier is added, and after being fully dispersed, it is heated to 60-80°C and stirred for 4-8 hours until the water is basically evaporated, dried for 12-18 hours, and calcined at 500-600°C for 2-3 hours to obtain a new catalyst.

[0094] Preparation method of Pt sintered catalyst: calcine the newly prepared catalyst at 800-900°C for 10-12h to obtain a Pt sintered catalyst.

[0095] Catalytic performance test: The regenerated platinum-based catalyst obtained in the embodiment and the comparative example is tableted and sieved to obtain a sample with a diameter of 60-80 mesh, 200 mg is taken, mixed with 600 mg of 60-80 mesh quartz sand, filled in a transparent fixed bed quartz reaction tube at room temperature, and the reactivity of the catalyst is evaluated in a fixed bed reaction device (CR06g, Tianjin Pengxiang Technology Co., Ltd.); wherein the catalyst is placed in the constant temperature section of the heating furnace, a certain amount of quartz sand is first filled in the fixed bed quartz reaction tube, and then the catalyst is loaded, and the upper and lower ends of the catalyst are fixed with quartz wool. During the propane dehydrogenation experiment, the total flow rate of the raw gas is 55 mL / min, propane: nitrogen (gas flow rate ratio) = 5:50, the reaction temperature is 600°C, the reaction pressure is 0.1 MPa, and the reaction time is 15 min. After the reaction, the catalytic performance of the regenerated platinum-based catalyst for the dehydrogenation of propane to produce propylene was analyzed online by a Fuli GC9790Plus gas chromatograph equipped with a hydrogen flame ionization detector (FID) and a thermal conductivity detector (TCD).

[0096] The performance test data is shown in Table 1. Figures 1 to 3 As shown:

[0097] Table 1. Catalytic performance test of examples and comparative examples

[0098]

[0099]

[0100] As can be seen from the data of Examples 1 to 5 in Table 1, when the reaction time and reaction temperature in step S1 are preferably 1 to 6 h and 50 to 100 ° C, respectively, the reaction of platinum, hydrogen peroxide and hydrochloric acid to generate chloroplatinic acid can be fully carried out, so the regenerated platinum-based catalyst has a more excellent catalytic performance for the reaction of propane dehydrogenation to prepare propylene, the target reaction selectivity is above 92.6% and the conversion rate of the reactant propane reaches more than 70.2%. When the reaction temperature in step S1 is lower than 50 ° C (Example 5), the generation of chloroplatinic acid is difficult to fully carry out, so the catalytic performance of the regenerated catalyst for the propane dehydrogenation reaction is reduced, and the propane conversion rate is reduced. As can be seen from the data of Examples 1, 7 to 10, when the calcination time and temperature in step S2 are preferably 1 to 4 h and 200 to 800 ° C, respectively, the regenerated platinum-based catalyst has excellent catalytic activity for the reaction of propane dehydrogenation. From the data of Examples 1 and 11-12, it can be seen that when the ratio of Pt, hydrochloric acid and hydrogen peroxide on the platinum-based catalyst after Pt sintering in step S1 is 2 mg: (0.5-2) mL: (0.5-2) mL, the regenerated platinum-based catalyst has excellent catalytic activity. From the data of Comparative Examples 1-2, it can be seen that hydrogen peroxide and hydrochloric acid are both critical to the regeneration of the platinum-based catalyst and are indispensable.

[0101] Figure 1 Figure 2 is the XRD pattern of the newly prepared, sintered and regenerated platinum-based catalyst of Example 1 of the present invention. Figure 1 It can be seen that the position of the XRD peak of the regenerated platinum-based catalyst is consistent with the position of the peak of the standard PDF card, and no impurity peaks appear at other positions, indicating that the regenerated platinum-based catalyst does not contain other impurities, and the peak intensity of Pt in the regenerated platinum-based catalyst is almost the same as that in the initial platinum-based catalyst. The diffraction peak intensity of the sintered platinum-based catalyst increases because platinum agglomerates under high temperature reaction conditions of 600°C, indicating that the crystallinity of the sintered platinum is improved.

[0102] Figure 2 HAADF-SEM images of (a) freshly prepared, (b) sintered and (c) regenerated platinum-based catalysts according to Example 1 of the present invention, (d) particle size images of freshly prepared and (f) regenerated platinum-based catalysts according to Example 1 of the present invention, and (e) HRTEM image of sintered platinum-based catalysts. Figure 2 It can be seen that the Pt particles in the newly prepared platinum-based catalyst are small and evenly distributed, with an average particle size of 4.5nm; the platinum-based catalyst after sintering is due to the agglomeration of platinum particles under high temperature conditions of 800-900℃, so the platinum particles are larger and more unevenly distributed, with an average particle size of 55.1nm; the regenerated platinum-based catalyst recovers to a Pt particle size similar to that of the newly prepared catalyst and is evenly distributed, with an average particle size of 4.5nm. Figure 2 (c) is a high-resolution transmission electron microscopy image of the sintered platinum-based catalyst, in which the lattice distance is 0.221 nm, corresponding to the (111) crystal plane of Pt.

[0103] Figure 3 The catalytic performance comparison diagram of the regenerated platinum-based catalyst obtained in Example 1 of the present invention, the platinum-based catalyst after Pt sintering, and the catalyst before Pt sintering. Figure 3 It can be seen that the catalytic performance of the platinum-based catalyst regenerated by the platinum-based catalyst regeneration method provided by the present invention for propane dehydrogenation reaction is similar to that of the newly prepared platinum-based catalyst, and is much higher than that of the platinum-based catalyst after platinum sintering.

[0104] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. An application of a regenerated platinum-based catalyst in catalytic propane dehydrogenation, the platinum-based catalyst comprising a catalyst carrier and an active component Pt supported on the carrier and sintered, characterized in that: The regeneration method of the platinum-based catalyst specifically comprises the following steps: S1. adding the sintered platinum-based catalyst to a mixed solution of hydrochloric acid and hydrogen peroxide and uniformly dispersing the mixture, and obtaining a regenerated platinum-based catalyst to be activated after sufficient reaction; S2. calcining the regenerated platinum-based catalyst to be activated obtained in step S1 to obtain a regenerated platinum-based catalyst; In the step S1, the ratio of Pt, hydrochloric acid and hydrogen peroxide on the platinum-based catalyst after Pt sintering is 2 mg: (0.5-2) mL: (0.5-2) mL; The platinum-based catalyst after Pt sintering is loaded with 3wt% of Ga2O3 as a dispersing aid.

2. The use according to claim 1, characterized in that: The calcination temperature in step S2 is 200-800°C.

3. The use according to claim 2, characterized in that: The calcination temperature in step S2 is 500-600°C.

4. The use according to claim 1, characterized in that: The reaction temperature in step S1 is 50-100°C.

5. The use according to claim 1, characterized in that: The reaction time in step S1 is 1 to 6 hours.

6. The use according to claim 5, characterized in that The reaction time in step S1 is 2 to 4 hours.

7. The use according to claim 1, characterized in that: The calcination time in step S2 is 1 to 4 hours.

8. The use according to claim 1, characterized in that The catalyst carrier in the platinum-based catalyst after the Pt sintering in the step S1 is a combination of SiO2 and Al2O3.

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