Hydrothermal-resistant and acid-resistant catalyst for efficiently catalyzing oxidation of polyol as well as preparation method and application of catalyst

Abstract

The invention provides a water-heat-resistant and acid-resistant catalyst for efficiently catalyzing polyol oxidation as well as a preparation method and application of the catalyst, and relates to the technical field of polyol oxidation catalysts. The hydrothermal-resistant and acid-resistant catalyst for efficiently catalyzing oxidation of polyol comprises a main active component, an auxiliary agent and a modified carrier, the main active component is at least one of Au, Pt and Pd; the auxiliary agent is at least one of Mn, Fe, Co, Ni, Cu, Sb and Bi; the carrier is at least one of SiO2, Al2O3, a TS-1 molecular sieve, a ZSM-5 molecular sieve and activated carbon. According to the invention, the activity and stability of the catalyst are enhanced by modifying the catalyst carrier and adding specific types of auxiliaries, so that the catalyst has excellent hydrothermal resistance and acid resistance. The raw materials of the catalyst are easy to obtain, the preparation process is simple, the reaction process is environment-friendly, and the catalyst is convenient to recycle, can be repeatedly used and shows a good industrial application prospect.

Description

Technical Field

[0001] The present invention relates to the technical field of polyol oxidation catalysts, and in particular to a water-resistant, heat-resistant and acid-resistant catalyst for efficiently catalyzing polyol oxidation, and a preparation method and application thereof. Background Art

[0002] The widespread use of petroleum-based chemicals has increased fossil energy consumption, leading to increasingly severe environmental pollution. These challenges have led to a growing interest in biomass, a rich and renewable resource. Polyols are high-value-added chemical raw materials produced through a series of processing techniques (such as pyrolysis and hydrogenation) from biomass resources such as lignocellulose, sugars, and oils. They can effectively alleviate fossil fuel consumption and environmental pollution.

[0003] The oxidation of alcohols is an important method for preparing unsaturated carbonyl compounds such as ketones and acids. Among the 12 biomass-based platform compounds for high-value-added chemicals proposed by the U.S. Department of Energy, the vast majority are polyols (such as glycerol and sorbitol) and carboxylic acid oxidation products of polyols (such as glucaric acid and 3-hydroxypropionic acid). These chemicals have very important applications in many important industrial fields, such as the synthesis of polymer materials, pharmaceuticals, and food.

[0004] There have been numerous research reports on the field of polyol oxidation. In terms of catalyst design, researchers have modified the carriers or active components of supported metal catalysts with metals or non-metals such as K, La, P, Bi, etc., to achieve catalyst modification and thereby improve the activity, service life and stability of the catalyst.

[0005] For example, the invention patent with publication number CN 104645983 A adds lanthanum, cerium, and zirconium compounds to hydrated alumina, and after calcining at 500-1000°C for a period of time, obtains an alumina carrier with high thermal stability, which is loaded with one or more of copper, silver, manganese, palladium, and platinum to obtain a circulating gas purification catalyst with excellent performance; the invention patent with publication number CN 111774087 A uses a bismuth salt, an organic precursor, and a nitrogen source through a mechanical mixing-calcination method to prepare a bismuth-modified porous carbon carrier, which is then loaded with precious metals to obtain a solid catalyst; the invention patent with publication number CN 114054031 A's invention patent discloses a catalyst for polyol oxidation, comprising an active component and a carrier; the active component comprises Fe element, and the carrier comprises a metal oxide of an IVB element, wherein the carrier is modified with a transition metal other than Fe. The preparation method of the catalyst comprises: (1) preparing a transition metal-modified TiO2 carrier by a sol-gel method; (2) impregnating the modified TiO2 carrier with an aqueous solution of ferric nitrate to obtain a precursor solution; and (3) drying and grinding the precursor solution and then calcining it in a muffle furnace to obtain the desired catalyst.

[0006] In addition, there are a large number of research reports on the design of bimetallic catalysts. For example: the invention patent with publication number CN114534723A discloses a catalyst for the selective oxidation of ethylene glycol to produce glycolic acid and its preparation method, which is composed of metal palladium as an active component, activated carbon as a carrier, and metal bismuth and cerium dioxide as auxiliary catalysts. The content of metal palladium is 0.1% to 1.5% of the weight of the carrier, and the total content of metal bismuth and cerium dioxide is 0.25% to 1.5% of the weight of the carrier. The invention patent with publication number CN 114029058 A discloses a catalyst for the catalytic oxidation of glycerol to produce 1,3-dihydroxyacetone, including an active component, an auxiliary agent and a carrier. The active component includes Au element, the auxiliary agent includes a mixture of one or more elements of Mg, Ca, Ba, Sr, Ni, Co, Cu, and Fe, and the carrier is ZnO. The invention patent with publication number CN 117753468 discloses a catalyst for the catalytic oxidation of glycerol to produce 1,3-dihydroxyacetone, including an active component, an auxiliary agent and a carrier. The active component includes Au element, and the auxiliary agent includes a mixture of one or more elements of Mg, Ca, Ba, Sr, Ni, Co, Cu, and Fe. The carrier is ZnO. A's invention patent discloses a supported catalyst for catalytic oxidation of glycerol to lactic acid, as well as its preparation method and application. The supported catalyst includes an active metal, an auxiliary metal and a carrier; wherein the active metal includes Pt, the auxiliary metal includes one or more of Zn, K, Co, Cu and Ni, and the carrier is a molecular sieve containing heteroatoms; the content of Lewis acid in the molecular sieve containing heteroatoms is 0.1 to 0.3 mmol / g.

[0007] The synergistic effect of additives and the noble metal primary active component in bimetallic catalysts not only reduces catalyst cost but also improves catalyst performance and reaction efficiency. Regarding raw material selection, most research focuses on the oxidation of C2-C4 polyols, with relatively little research on the catalytic oxidation of polyols with higher carbon numbers.

[0008] Catalyst performance is a key indicator of catalyst quality. Different reactions and reaction conditions require different catalyst performance, such as heat resistance and corrosion resistance. Among existing polyol catalytic oxidation catalysts, few studies have examined their hydrothermal and acid resistance. For example, patent publication CN 114534723A discloses a method for preparing an activated carbon-supported Pt-Bi-CeO2 catalyst for oxidizing ethylene glycol to glycolic acid. The use of flaky or granular activated carbon improves the catalyst's alkali resistance. Patent publications CN 118079951 A, CN 108911961 A, and CN 105439831A, respectively, disclose catalysts for catalyzing the oxidation of polyols to acids under alkali-free or non-alkaline conditions. However, the hydrothermal and acid resistance of the catalysts is not addressed.

[0009] Because the raw materials used in most research and industrial applications of polyol oxidation reactions are aqueous solutions, and the reaction products are accompanied by the generation of acid, the reaction system requires catalysts with excellent hydrothermal and acid resistance to ensure stable catalytic activity during operation. Therefore, improving the hydrothermal and acid resistance of catalysts while maintaining good catalytic activity, selectivity, and stability is crucial for the preparation of high-value-added chemicals using polyols as raw materials. Summary of the Invention

[0010] In light of this, the present invention provides a hydrothermal and acid-resistant catalyst for the efficient catalytic oxidation of polyols, as well as its preparation method and application. By modifying the catalyst support and adding specific additives, the present invention improves the activity and stability of the catalyst, enabling it to maintain good catalytic activity and stability even in an aqueous reaction system with an acidic pH. Furthermore, the catalyst features readily available raw materials, a simple preparation process, environmental friendliness, and easy recycling, demonstrating promising prospects for industrial application.

[0011] A hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols comprises a main active component, an auxiliary agent and a modified carrier.

[0012] Preferably, the main active component is at least one of Au, Pt, and Pd, more preferably Pt; the auxiliary agent is at least one of Mn, Fe, Co, Ni, Cu, Sb, and Bi, more preferably Cu; the modified carrier is obtained by modifying the carrier; the carrier is at least one of SiO2, Al2O3, TS-1 molecular sieve, ZSM-5 molecular sieve, and activated carbon, more preferably SiO2; the mass ratio of the main active component to the modified carrier is (0.5-3):100; the mass of the auxiliary agent accounts for 0.1%-10% of the total mass of the catalyst.

[0013] Preferably, the preparation method of the modified carrier is as follows:

[0014] The modifier is mixed with the carrier, dried, and calcined to obtain a modified carrier;

[0015] The modifier is a silane coupling agent; the mass ratio of the modifier to the carrier is 1:10; the drying temperature is 70°C-100°C, preferably 70°C, and the drying time is 5-10h, preferably 5h; the calcination temperature is 500°C, and the calcination time is 4-6h, preferably 4h.

[0016] The second aspect of the present invention is to provide a method for preparing a water-resistant, heat-resistant and acid-resistant catalyst that can efficiently catalyze the oxidation of polyols. The preparation method is an immersion reduction method or a solvent reduction method.

[0017] Preferably, the impregnation reduction process for preparing the hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols comprises the following steps:

[0018] After the modified support is dried, the main active component precursor solution and the auxiliary agent metal salt solution are added dropwise, stirred evenly, aged and dried to obtain powder A;

[0019] After calcination, powder A is reduced in a hydrogen atmosphere, cooled, and ground to obtain a hydrothermal and acid-resistant catalyst that efficiently catalyzes the oxidation of polyols;

[0020] The drying temperature of the modified carrier is 70°C-100°C, preferably 70°C, and the drying time is 5-10h, preferably 5h; the main active component precursor is the nitrate, sulfate or chloride of the corresponding main active component; the solvent of the solution is at least one of water, ethanol and isopropanol; the calcination temperature is 500°C, and the calcination time is 4-6h, preferably 4h; the reduction temperature is 400°C, and the reduction time is 5-6h, preferably 5h.

[0021] Preferably, the solvent reduction process for preparing the hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols comprises the following steps:

[0022] The modified carrier is mixed with a solvent to obtain a suspension A;

[0023] Add the main active component precursor solution and the auxiliary metal salt solution to the suspension A and stir evenly to obtain a mixture B;

[0024] The sodium borohydride solution is added dropwise to the mixture B, and after the reaction, the mixture is allowed to stand for aging, filtered, and dried to obtain a hydrothermal and acid-resistant catalyst that efficiently catalyzes the oxidation of polyols;

[0025] The precursor of the main active component is a nitrate, sulfate or chloride of the corresponding main active component; the solvent of the solution is at least one of water, ethanol and isopropanol; the reaction is carried out under stirring conditions, the reaction temperature is 70°C-80°C, preferably 70°C, and the reaction time is 8-10h, preferably 8h; the aging temperature is 25°C, the aging time is 8-12h, preferably 8h; the drying temperature is 60°C-120°C, and the drying time is 1-24h.

[0026] The third aspect of the present invention is to provide the use of the catalyst in the catalytic oxidation reaction of polyols under hydrothermal and acidic conditions.

[0027] Preferably, the polyol catalytic oxidation reaction is carried out with water as solvent and air or O2 as oxidant under strong stirring (1000r / min), the reaction temperature is 50℃-200℃, the reaction pressure is from normal pressure to 5MPa, and the reaction time is 1-24h.

[0028] Compared with the prior art, the present invention has the following beneficial technical effects:

[0029] The present invention improves the loading capacity and stability of the carrier for the main active component by modifying the catalyst carrier.

[0030] The invention improves the dispersion of the main active component in the carrier by adding a specific type of auxiliary agent, reduces the amount of the main active component to save the production cost of the catalyst, and improves the activity and stability of the catalyst through the interaction between the auxiliary agent and the main active component.

[0031] The catalyst prepared by the invention has good hydrothermal and acid resistance in the polyol oxidation reaction, that is, it can still maintain good catalytic activity and stability for the catalytic oxidation of polyols when the reaction system is in an aqueous phase and the pH is acidic.

[0032] The catalyst of the present invention has readily available reaction raw materials, a simple preparation process, an environmentally friendly reaction process, is easy to recycle, can be reused, and has good industrial application prospects. DETAILED DESCRIPTION

[0033] The following will clearly and completely describe the technical solutions of the present invention in conjunction with the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0034] The first aspect of the present invention is to provide a hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols, the catalyst comprising a main active component, an auxiliary agent and a modified carrier;

[0035] The main active component is at least one of Au, Pt, and Pd, preferably Pt; the auxiliary agent is at least one of Mn, Fe, Co, Ni, Cu, Sb, and Bi, preferably Cu; the modified carrier is obtained by modifying the carrier; the carrier is at least one of SiO2, Al2O3, TS-1 molecular sieve, ZSM-5 molecular sieve, and activated carbon, preferably SiO2; the mass ratio of the main active component to the carrier is (0.5-3):100; the mass of the auxiliary agent accounts for 0.1%-10% of the total mass of the catalyst.

[0036] The preparation method of the modified carrier of the present invention is as follows:

[0037] The modifier is mixed with the carrier, dried, and calcined to obtain a modified carrier;

[0038] The modifier is a silane coupling agent; the mass ratio of the modifier to the carrier is 1:10; the drying temperature is 70°C-100°C, preferably 70°C, and the drying time is 5-10h, preferably 5h; the calcination temperature is 500°C, and the calcination time is 4-6h, preferably 4h.

[0039] The second aspect of the present invention is to provide a method for preparing a water-resistant, heat-resistant and acid-resistant catalyst that can efficiently catalyze the oxidation of polyols. The preparation method is an immersion reduction method or a solvent reduction method.

[0040] The impregnation reduction process for preparing the hydrothermal and acid-resistant catalyst for high-efficiency catalytic oxidation of polyols of the present invention comprises the following steps:

[0041] After the modified support is dried, the main active component precursor solution and the auxiliary agent metal salt solution are added dropwise, stirred evenly, aged and dried to obtain powder A;

[0042] After calcination, powder A is reduced in a hydrogen atmosphere, cooled, and ground to obtain a hydrothermal and acid-resistant catalyst that efficiently catalyzes the oxidation of polyols;

[0043] The drying temperature of the modified carrier is 70°C-100°C, preferably 70°C, and the drying time is 5-10h, preferably 5h; the main active component precursor is the nitrate, sulfate or chloride of the corresponding main active component; the solvent of the solution is at least one of water, ethanol and isopropanol; the calcination temperature is 500°C, and the calcination time is 4-6h, preferably 4h; the reduction temperature is 400°C, and the reduction time is 5-6h, preferably 5h.

[0044] The solvent reduction process for preparing the hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols of the present invention comprises the following steps:

[0045] The modified carrier is mixed with a solvent to obtain a suspension A;

[0046] Add the main active component precursor solution and the auxiliary metal salt solution to the suspension A and stir evenly to obtain a mixture B;

[0047] The sodium borohydride solution is added dropwise to the mixture B, and after the reaction, the mixture is allowed to stand for aging, filtered, and dried to obtain a hydrothermal and acid-resistant catalyst that efficiently catalyzes the oxidation of polyols;

[0048] The precursor of the main active component is a nitrate, sulfate or chloride of the corresponding main active component; the solvent of the solution is at least one of water, ethanol and isopropanol; the reaction is carried out under stirring conditions, the reaction temperature is 70°C-80°C, preferably 70°C, and the reaction time is 8-10h, preferably 8h; the aging temperature is 25°C, the aging time is 8-12h, preferably 8h; the drying temperature is 60°C-120°C, and the drying time is 1-24h.

[0049] The third aspect of the present invention is to provide the use of the catalyst in the catalytic oxidation reaction of polyols under hydrothermal and acidic conditions.

[0050] The polyol catalytic oxidation reaction is carried out with water as solvent and air or O2 as oxidant under strong stirring (1000r / min), the reaction temperature is 50℃-200℃, the reaction pressure is from normal pressure to 5MPa, and the reaction time is 1-24h.

[0051] In order to further illustrate the present invention, the following examples are provided for detailed description. The raw materials used in the following examples of the present invention are all commercially available.

[0052] Unless otherwise specified, all experiments were repeated three times and the results were expressed as the mean value.

[0053] Example 1 The preparation method of the modified carrier is as follows:

[0054] 10 g of silica, alumina, TS-1 molecular sieve, ZSM-5 molecular sieve and activated carbon were respectively mixed with 1 g of silane coupling agent KH550, mixed evenly and dried at 70°C for 5 h, and then calcined at 500°C for 4 h to obtain a modified support.

[0055] Example 2 Preparation of Pt-Cu / SiO2 catalyst, the steps are as follows:

[0056] (1) 5 g of the modified SiO2 support in Example 1 was dried at 70°C for 5 h, 0.275 g of chloroplatinic acid hexahydrate was dissolved in 25 mL of deionized water, stirred evenly, and then added dropwise to the dried support, stirring vigorously throughout the process to ensure full absorption by the support, to obtain impregnation solution 1;

[0057] (2) Dissolve 0.292 g of copper nitrate in 25 ml of anhydrous ethanol, stir evenly, and add dropwise to impregnation solution 1, stirring vigorously throughout the process to ensure that the support is fully absorbed, to obtain impregnation solution 2;

[0058] (3) Impregnation solution 2 was aged overnight at 25°C and dried at 70°C for 5 h. The catalyst was then calcined in a muffle furnace at 500°C for 4 h. Finally, the catalyst was reduced in a tube furnace at 400°C in a hydrogen atmosphere for 5 h. After cooling, the catalyst was milled in a ball mill at a ball-to-material ratio of 15:1 and a rotation speed of 50 rpm for 30 min to obtain a Pt-Cu / SiO2 catalyst. The catalyst had a Pt content of 2 wt.% and a Cu content of 1.5 wt.%.

[0059] Example 3 Preparation of Pt-Cu / SiO2 catalyst, the steps are as follows:

[0060] (1) 5 g of the modified SiO2 support in Example 1 was mixed with 150 mL of deionized water to obtain a suspension 1;

[0061] (2) 0.275 g of chloroplatinic acid hexahydrate and 0.292 g of copper nitrate were added to suspension 1 and stirred for 10 min to form mixture 2;

[0062] (3) 0.07 g of sodium borohydride was dissolved in 100 mL of deionized water to prepare a sodium borohydride solution, which was then added dropwise to the suspension at a rate of 3-5 drops / second. After the addition was complete, the solution was stirred at a constant temperature of 70° C. for 8 h, allowed to stand for aging for 8 h, filtered, and dried at 70° C. for 12 h to obtain a Pt-Cu / SiO2 catalyst. The catalyst had a Pt content of 2 wt.% and a Cu content of 1.5 wt.%.

[0063] Example 4

[0064] 0.216 g of palladium nitrate and 0.173 g of chloroauric acid were dissolved in 25 ml of deionized water, respectively, and the remaining steps were the same as in Example 2. Finally, Pd-Cu / TiO2 catalyst and Au-Cu / TiO2 catalyst were obtained respectively.

[0065] Example 5

[0066] 0.246 g of manganese nitrate, 0.545 g of ferric nitrate nonahydrate, 0.373 g of cobalt nitrate hexahydrate, 0.374 g of nickel nitrate, and 0.076 g of antimony chloride were dissolved in 25 mL of anhydrous ethanol, and 0.143 g of bismuth nitrate was dissolved in 25 mL of isopropanol. The remaining steps were the same as in Example 2. Finally, Pt-Mn / SiO2 catalyst, Pt-Fe / SiO2 catalyst, Pt-Co / SiO2 catalyst, Pt-Ni / SiO2 catalyst, Pt-Sb / SiO2 catalyst, and Pt-Bi / SiO2 catalyst were obtained, respectively. In each of the above catalysts, the Pt content was 2 wt.%, and the content of the additives (Mn, Fe, Co, Ni, Sb, Bi) was 1.5 wt.%.

[0067] Example 6

[0068] 0.069 g, 0.137 g, and 0.550 g of chloroplatinic acid hexahydrate were weighed, respectively, and dissolved in 25 ml of deionized water. The remaining steps were the same as in Example 2. Finally, Pt-Cu / SiO2 catalysts with active component contents of 0.5 wt.%, 1 wt.%, and 4 wt.% were prepared, which were respectively designated as Pt(0.5)-Cu / SiO2 catalyst, Pt(1)-Cu / SiO2 catalyst, and Pt(2)-Cu / SiO2 catalyst.

[0069] Example 7

[0070] Using 5 g of dried modified alumina, modified TS-1 molecular sieve, ZSM-5 molecular sieve, and activated carbon as supports, the remaining steps were the same as in Example 2 to prepare Pt-Cu / Al2O3 catalysts, Pt-Cu / TS-1 catalysts, Pt-Cu / ZSM-5 catalysts, and Pt-Cu / AC catalysts. In each of these catalysts, the Pt content was 2 wt.%, and the Cu content was 1.5 wt.%.

[0071] Test Example 1

[0072] The catalyst prepared in Example 2-7 was applied to oxidize glycerol to glyceric acid / lactic acid in the following steps:

[0073] 0.2 g of each catalyst and 25 mL of a 0.1 mol / L aqueous glycerol solution were added to a 25 mL autoclave, and the reaction was carried out at 80°C, a stirring rate of 1000 rpm, and a reaction time of 9 hours. After the reaction, the reaction solution was filtered using a disposable needle and a syringe filter. The filtrate was analyzed by chromatography, and the glycerol conversion, glyceric acid selectivity, and lactic acid selectivity were calculated. The results are shown in Table 1.

[0074] Table 1 Glycerol oxidation experimental results

[0075]

[0076] In the above experiments, the reaction product is acidic and the pH of the reaction system is 1.7-2.5.

[0077] According to the data in Table 1, the following conclusions can be drawn:

[0078] The Pt-Cu / SiO2 prepared by impregnation gave the highest glycerol conversion and glycerate / lactic acid selectivity;

[0079] When the Pt loading is 2wt%, the catalytic performance of Pt-Cu / SiO2 is the best;

[0080] The highest glycerol conversion and glycerate / lactic acid selectivity were obtained by using Pt as the active component;

[0081] The highest glycerol conversion and glycerate / lactic acid selectivity were obtained by using Pt as the active component and Cu as the additive loaded on SiO2 support.

[0082] The highest glycerol conversion and glycerate / lactic acid selectivity were obtained by using Pt as the active component and Cu as the additive loaded on SiO2 support.

[0083] In summary, when Pt-Cu / SiO2 catalyst catalyzes glycerol oxidation, the glycerol conversion rate and glyceric acid / lactic acid selectivity are both very high.

[0084] Test Example 2

[0085] The Pt-Cu / SiO prepared by 0.2g embodiment 2 Catalyst and 25mL 0.1mol / L glycerol aqueous solution are added respectively in 25mL autoclave, are filled with 0.5MPa oxygen and react, described reaction temperature 80 DEG C, stir speed (S.S.) is 1000r / min, and reaction time is 9h.After reaction terminates, disposable needle and syringe filter are used to filter reaction solution, take filtrate and carry out chromatographic analysis. The catalyst deionized water and ethanol washing of recovery are dried at 70 DEG C for 5h, then reacted again, repeated operation, calculate glycerol conversion, glyceric acid selectivity and lactic acid selectivity, test the cyclic performance of catalyst, the results are shown in Table 2.

[0086] Table 2 Catalytic glycerol oxidation cycle performance test results

[0087]

[0088] Test Example 3

[0089] The Pt-Cu / SiO2 catalyst prepared in Example 2 was applied to the oxidation of ethylene glycol to glycolic acid to test the stability and hydrothermal and acid resistance of the catalyst. The steps were as follows:

[0090] 0.2g of Pt-Cu / SiO2 catalyst and 25mL of 0.1mol / L aqueous ethylene glycol solution were added to a 25mL autoclave and charged with 1MPa of oxygen. The reaction was carried out at 70°C, with a stirring rate of 1000 rpm and a reaction time of 6 hours. After the reaction, the reaction liquid was filtered using a disposable needle and a syringe filter. The filtrate was subjected to chromatographic analysis. The recovered catalyst was washed with deionized water and ethanol, dried at 70°C for 5 hours, and retested for reactivity without any further treatment. This process was repeated several times. The results are shown in Table 3.

[0091] Table 3 Catalytic ethylene glycol oxidation cycle performance test results

[0092]

[0093] In the above experiments, the reaction product is acidic and the pH of the reaction system is 1.5-2.6.

[0094] As shown in Table 3, in the reaction of ethylene glycol oxidation to glycolic acid, the ethylene glycol conversion remained high after five rounds of reaction, and the glycolic acid selectivity decreased by no more than 3%. This indicates that the Pt-Cu / SiO2 catalyst of the present invention has excellent chemical stability.

[0095] The reaction products of Test Example 1 and Test Example 2 are acidic. Each catalytic reaction is carried out in an aqueous acidic medium. After the catalyst stability test, the performance of the catalyst can still be maintained at a high level, indicating that the catalyst has good water, heat and acid resistance.

[0096] Comparative Example 1

[0097] The difference from Example 2 is that the carrier is not modified.

[0098] The cyclic performance of the catalyst was tested using the same testing method as in Test Examples 2 and 3. The results are shown in Tables 4 and 5.

[0099] Table 4 Catalyst catalytic glycerol oxidation cycle performance test results

[0100]

[0101] Table 5 Catalyst catalytic ethylene glycol oxidation cycle performance test results

[0102]

[0103] Comparative Example 2

[0104] The difference from Example 2 is that the silane coupling agent KH550 is replaced by an equal amount of silane coupling agent KH590.

[0105] The cyclic performance of the catalyst was tested using the same testing method as in Test Examples 2 and 3. The results are shown in Tables 6 and 7.

[0106] Table 6 Catalyst catalytic glycerol oxidation cycle performance test results

[0107]

[0108]

[0109] Table 7 Catalyst catalytic ethylene glycol oxidation cycle performance test results

[0110]

[0111] The above-described embodiments merely illustrate several implementations of the present invention, and while their descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the patent. It should be noted that a person skilled in the art would be able to make numerous variations and improvements without departing from the spirit of the present invention, all of which fall within the scope of protection of the present invention. Therefore, the scope of protection of the patent for this invention shall be determined by the appended claims.

Claims

1. A hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols, characterized in that: The catalyst includes a main active component, an auxiliary agent and a modified carrier; The main active component is at least one of Au, Pt, and Pd; The auxiliary agent is at least one of Mn, Fe, Co, Ni, Cu, Sb, and Bi; The modified carrier is obtained by modifying the carrier; the carrier is at least one of SiO2, Al2O3, TS-1 molecular sieve, ZSM-5 molecular sieve, and activated carbon.

2. The hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols according to claim 1, characterized in that: The preparation method of the modified carrier is as follows: The modifier is mixed with the carrier, dried, and calcined to obtain the modified carrier.

3. The hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols according to claim 2, characterized in that: The modifier is a silane coupling agent.

4. The hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols according to claim 2, characterized in that: The mass ratio of the modifier to the modified carrier is 1:

10.

5. The method for preparing the hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols according to any one of claims 1 to 4, characterized in that: The preparation method is an impregnation reduction method or a solvent reduction method.

6. The preparation method according to claim 5, characterized in that The impregnation reduction method comprises the following steps: After the modified support is dried, the main active component precursor solution and the auxiliary agent metal salt solution are added dropwise, stirred evenly, aged and dried to obtain powder A; After calcination, powder A is reduced in a hydrogen atmosphere, cooled, and ground to obtain a water-resistant, heat-resistant, and acid-resistant catalyst that can efficiently catalyze the oxidation of polyols.

7. The preparation method according to claim 5, characterized in that The solvent reduction method comprises the following steps: The modified carrier is mixed with a solvent to obtain a suspension A; Add the main active component precursor solution and the auxiliary metal salt solution to the suspension A and stir evenly to obtain a mixture B; The sodium borohydride solution is added dropwise to the mixture B. After the reaction, the mixture is allowed to stand for aging, filtered, and dried to obtain a water-resistant, heat-resistant, and acid-resistant catalyst that efficiently catalyzes the oxidation of polyols.

8. Use of a hydrothermal and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols in a polyol catalytic oxidation reaction, characterized in that: The hydro-heat-resistant and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols is the hydro-heat-resistant and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols described in any one of claims 1-4 or the hydro-heat-resistant and acid-resistant catalyst for efficiently catalyzing the oxidation of polyols prepared by the method described in any one of claims 5-7.

9. The use according to claim 8, characterized in that The polyol catalytic oxidation reaction is carried out with water as solvent and air or O2 as oxidant under strong stirring.

10. The use according to claim 8, characterized in that The reaction temperature is 50° C.-200° C., the reaction pressure is normal pressure to 5 MPa, and the reaction time is 1-24 h.

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