Oxidation catalyst and method for preparing glyceric acid through catalytic oxidation of glycerol by using oxidation catalyst

Abstract

The invention belongs to the technical field of biomass catalytic conversion and comprehensive utilization of mineral resources, and particularly relates to an oxidation catalyst and a method for preparing glyceric acid by catalyzing and oxidizing glycerol through the oxidation catalyst. According to the method, the catalyst is prepared from the components of the low-grade lithium ore, the synergetic catalysis effect of Li, Al, Si, associated K, F and other components in the ore is activated through the composite pretreatment process of enhanced mechanical activation, high-concentration acid leaching and high-temperature step-by-step roasting, the Li-Al-Si-K-F composite oxide heterogeneous catalyst is constructed, oxygen is used as an oxidizing agent, and the high-quality lithium ion battery anode material is obtained. And efficient conversion from glycerol to glyceric acid is realized in a pure water medium.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of biomass catalytic conversion and comprehensive utilization of mineral resources, and particularly relates to an oxidation catalyst and a method for preparing glyceric acid by catalytic oxidation of glycerol. BACKGROUND

[0002] Glyceric acid is a simple organic acid and an intermediate product of glycerol metabolism, and is naturally present in some fruits (such as pineapples and bananas). As a multifunctional and highly valuable fine chemical, it has a wide range of applications from basic metabolism to commercial applications, and has shown important application potential in many fields, with a growing demand.

[0003] At present, there are many conversion pathways for glycerol. Compared with other pathways, oxidation is an effective way to generate high-value-added products. At present, the typical catalyst for glycerol oxidation to obtain value-added products is three noble metals Au, Pt and Pd and their corresponding alloys. However, such noble metal supported catalysts have problems such as dependence on alkaline conditions, harsh reaction conditions (alkaline medium, high pressure), easy deactivation of active sites, and low recovery rate. Due to the presence of noble metals, the cost of the entire process is also high. Therefore, more attention has been paid to the exploration of glyceric acid oxidation catalysts.

[0004] Lithium ore is the core carrier of lithium resources, but low-grade lithium ore (Li2O < 2%) is mostly stored as tailings due to poor economic efficiency of lithium extraction, resulting in serious waste of resources. Existing research focuses on lithium extraction or catalytic application of high-grade lithium ore (such as spodumene with Li2O≥6%), and has not involved the construction of catalytic system of low-grade lithium ore. The field expects to develop more new applications, which has positive significance for the comprehensive utilization of lithium ore. SUMMARY

[0005] The first object of the present application is to provide an alkali-free normal pressure oxidation catalyst prepared by using the natural ingredients of low-grade lithium ore, which can catalyze the oxidation of glycerol to prepare glyceric acid under alkali-free, normal pressure and mild conditions, thereby effectively reducing the cost, simplifying the process and realizing the high value of low-grade mineral resources. The second object of the present application is to provide a method for preparing glyceric acid by catalytic oxidation of glycerol under alkali-free, normal pressure and mild conditions, which effectively solves the problems of dependence on noble metals, harsh reaction conditions and insufficient resource utilization of low-grade lithium ore in the prior art.

[0006] In order to solve the above technical problems, the present application provides a preparation method of an oxidation catalyst, comprising the following steps: (1) taking low-grade lithium ore, crushing and activating to obtain activated ore powder; (2) adding the activated ore powder into acid solution for impregnation strengthening, and collecting the filter residue by solid-liquid separation; (3) under a protective atmosphere, the filter residue is sequentially subjected to pre-calcination at 350-450°C and calcination at 700-800°C, to obtain the desired oxidation catalyst.

[0007] Specifically, in the preparation method of the oxidation catalyst, in the step (1), the low-grade lithium ore is a lithium polymetallic ore containing 1.5%-2.0wt% Li2O, and the main chemical components include SiO2≥60wt%, Al2O315-20wt%, and associated K2O and F elements. Preferably, the crushing step includes the step of crushing the low-grade lithium ore to 300-400 mesh.

[0008] Specifically, in the preparation method of the oxidation catalyst, in the step (1), the activation treatment includes the step of mechanical activation treatment. Preferably, the ball-to-material ratio in the activation treatment step is controlled to be 15:1-20:1. Preferably, the rotation speed in the activation treatment step is controlled to be 150-200rpm. Preferably, the activation time in the activation treatment step is controlled to be 4-6h.

[0009] Specifically, in the preparation method of the oxidation catalyst, in the step (2), the acid solution includes a dilute sulfuric acid solution or a phosphoric acid solution. Preferably, the acid solution includes a dilute sulfuric acid solution with a mass concentration of 10-15wt% or a phosphoric acid solution with a mass concentration of 12-18%. Preferably, the liquid-to-solid mass ratio of the activated ore powder to the acid solution is 8:1-10:1. Preferably, the temperature in the impregnation strengthening step is 70-95°C. Preferably, the time in the impregnation strengthening step is 8-12h.

[0010] In some specific embodiments, the acid solution includes a dilute sulfuric acid solution with a mass concentration of 10-15wt%, and the temperature in the impregnation strengthening step is 70-90°C.

[0011] In some specific embodiments, the acid solution includes a phosphoric acid solution with a mass concentration of 12-18%, and the temperature in the impregnation strengthening step is 80-95°C.

[0012] Specifically, in the preparation method of the oxidation catalyst, in the step (3): the treatment time in the pre-calcination step is 2-3h; and / or, the treatment time in the calcination step is 3-4h; and / or, The protective atmosphere comprises an inert gas with a flow rate of 0.8-1.5 L / min.

[0013] The application further discloses an oxidation catalyst prepared by the method.

[0014] The application further discloses application of the oxidation catalyst in a process of catalytically oxidizing glycerol to prepare glyceric acid.

[0015] The application further discloses a method for catalytically oxidizing glycerol to prepare glyceric acid, which comprises the step of carrying out an oxidation reaction by taking glycerol and oxygen as raw materials in the presence of the oxidation catalyst.

[0016] Specifically, the method for catalytically oxidizing glycerol to prepare glyceric acid comprises the following steps: The mass concentration of the glycerol is 10-30 wt%; and / or, The molar ratio of the oxygen to the glycerol is 30:1-60:1, and / or, The mass ratio of the catalyst to the glycerol is 0.3:1-0.5:1; and / or, The temperature of the oxidation reaction is 70-90℃; and / or, The pressure of the oxidation reaction is normal pressure; and / or, The time of the oxidation reaction is 24-36 h.

[0017] Specifically, the method for catalytically oxidizing glycerol to prepare glyceric acid further comprises the step of adding a promoter. Preferably, the promoter comprises potassium oxalate and / or MnSO4. Preferably, the addition amount of the promoter accounts for 1-3 wt% of the mass of the glycerol.

[0018] The oxidation catalyst disclosed by the application is prepared by taking low-grade lithium ore as raw material, strengthening mechanical activation to destroy the dense structure of the ore, selectively dissolving Li, Al, K and other active components by high-concentration acid leaching and regulating Si-based skeleton, and further promoting the reconstruction of Li-Al-Si-K-F composite active phase by high-temperature step-by-step calcination. + , K + The active site electronic density is synergistically regulated, F modifies the surface acidity to enhance glycerol adsorption, and the Si-based skeleton ensures the structural stability. The oxidation catalyst can catalyze the oxidation of glycerol to prepare glyceric acid under the conditions of no alkaline, normal pressure and temperature. The catalyst breaks through the limitation of raw materials, utilizes Li, Al, Si and associated K, F and other components in low-grade lithium ore, constructs an efficient catalytic system through process optimization, realizes the synergistic utilization of glycerol oxidation and mineral resources, can effectively reduce the cost, simplify the process and realize the high value of low-grade mineral resources.

[0019] The oxidation catalyst described in the application is aimed at low-grade lithium ore with low Li content, high SiO2 and Al2O3 proportion, and associated elements such as K and F. In the mechanical activation operation, the time is prolonged (4-6h), the ball-to-material ratio is increased (15:1-20:1), and the rotation speed is increased (150-200rpm), which greatly increases the lattice defects of the ore, reduces the Li-O and K-O bond energy, and provides a basis for subsequent acid leaching.

[0020] The oxidation catalyst described in the application is aimed at low-grade lithium ore with low Li content, high SiO2 and Al2O3 proportion, and associated elements such as K and F. In the intensified acid leaching operation, the acid concentration is increased (10%-15% dilute sulfuric acid), the liquid-to-solid ratio is increased (8:1-10:1), and the temperature is increased (70-90℃), which ensures the sufficient dissolution of low-content Li and K, while retaining the integrity of the Si-based skeleton.

[0021] The oxidation catalyst described in the application is aimed at low-grade lithium ore with low Li content, high SiO2 and Al2O3 proportion, and associated elements such as K and F. In the high-temperature calcination step, a step-by-step calcination method is used, pre-calcination (350-450℃) is used to remove impurities and moisture, and main calcination (700-800℃) is used to promote the crystallization of Li-Al-Si-K-F composite oxides, forming a stable catalytically active phase.

[0022] The oxidation catalyst described in the application can use the Inner Mongolia mine area's Vlasost lithium ore with Li2O 1.71% as raw material, and utilize its high SiO2 (60.52%), Al2O3 (17.12%), and associated K2O (5.44%) and F (6.33%) to activate the synergistic catalytic effect through process optimization, which has better adaptability to raw materials.

[0023] The method for preparing glyceric acid by catalytic oxidation of glycerol described in the application uses the oxidation catalyst for catalytic reaction, and by appropriately increasing the catalyst dosage (0.3:1-0.5:1), the reaction temperature (70-90℃), and the reaction time (24-36h), the activity and selectivity are balanced; oxygen or high-flow air is introduced to ensure oxygen supply, which effectively guarantees the conversion efficiency and reaction selectivity of glycerol.

[0024] The application first uses low-grade lithium ore (Li2O≤2%) in the catalytic system, realizes the high value of tailings-grade mineral resources, expands the source of raw materials, and the Li-Al-Si-K-F composite structure of the catalyst is wear-resistant, sintering-resistant, and has good reusability, stable catalytic performance, and meets the needs of industrial continuous production. The method for preparing glyceric acid by catalytic oxidation of glycerol does not require noble metals, utilizes natural ore components, does not require alkali, and performs reaction under normal pressure, which reduces wastewater and equipment investment, and the product separation is simple, having cost and environmental protection advantages.

[0025] The oxidation catalyst described in the application uses tailing grade low-grade lithium ore with low Li content as raw material, and the prepared oxidation catalyst has the same catalytic reaction performance as traditional high-grade lithium ore catalyst and traditional noble metal catalyst, can realize glycerol oxidation to prepare glyceric acid in pure water medium, and the whole reaction can be completed under normal pressure. The catalytic reaction not only has similar reaction effect to the existing technology based on high-grade lithium ore catalyst and noble metal catalyst, but also realizes the resource utilization of low-grade lithium ore, breaks the resource limitation of high-grade lithium ore, and solves the cost limitation of traditional carbon nanotube catalyst carrier needing to be loaded with noble metal such as Pt / Au, and has better process application value.

[0026] The application discloses a method for preparing a catalyst by using components of low-grade lithium ore, and catalyzing and oxidizing glycerol to prepare glyceric acid under the conditions of no alkaline and normal pressure and temperature. Through a composite pretreatment process of reinforced mechanical activation-high concentration acid leaching-high temperature step-by-step roasting, the synergistic catalytic action of Li, Al, Si and associated K, F and other components in the ore is activated, a Li-Al-Si-K-F composite oxide heterogeneous catalyst is constructed, oxygen is used as an oxidizing agent, and efficient conversion of glycerol to glyceric acid is realized in pure water medium. The application breaks the raw material limitation of high-grade lithium ore, has low catalyst preparation cost and is environment-friendly, and solves the problems of resource utilization of low-grade lithium ore and dependence of existing glycerol oxidation technology on noble metal and harsh reaction conditions. BRIEF DESCRIPTION OF DRAWINGS

[0027] In order to make the content of the application more easily understood, the application will be further described in detail below according to specific embodiments of the application and in combination with the drawings, in which, Figure 1 The XRD pattern of the catalyst prepared based on the low-grade lithium ore in Example 1 is shown in the figure, and it is shown that the ore forms LiAlO2-SiO2-KF composite phase after treatment. DETAILED DESCRIPTION

[0028] In the following examples of the application, an oxidation catalyst is provided, which uses tailing grade low-grade lithium ore with low Li content as raw material, and the prepared oxidation catalyst has the same catalytic reaction performance as traditional high-grade lithium ore catalyst and traditional noble metal catalyst, and can realize glycerol oxidation to prepare glyceric acid in pure water medium.

[0029] In Examples 1-3 of the application, as an exemplary embodiment, lithium polymetallic ore in the Weilasituo mining area of Hexigten Banner in Inner Mongolia is selected, and the component information is shown in Tables 1-2.

[0030] Table 1 Semi-quantitative analysis results of X fluorescence spectrum of raw ore

[0031] Table 2. Results of multi-element chemical analysis of the ore.

[0032] Example 1 This study uses lithium polymetallic ore from the Vilastow mining area in Keshiketeng Banner, Inner Mongolia Autonomous Region as raw material to prepare an oxidation catalyst, which is then used to catalyze the oxidation of glycerol to prepare glyceric acid.

[0033] The preparation method of the oxidation catalyst described in this embodiment includes the following steps: (1) Raw material pretreatment: Lithium polymetallic ore from the Vilasto mining area (Li2O content 1.71%) in Keshiketeng Banner, Inner Mongolia Autonomous Region, was crushed to 350 mesh, mechanically activated for 5 hours, and the ball-to-material ratio was adjusted to 18:1 and the rotation speed was 180 rpm. (2) Enhanced acid leaching: Add activated mineral powder to 12wt% dilute sulfuric acid solution and mix, adjust the liquid-solid ratio to 10:1, stir and react at 80℃ for 10h, filter and collect the filter residue; (3) Stepwise calcination: Under an inert atmosphere (argon, flow rate of 1.2 L / min), the filter residue was pre-calcined at 400 °C for 2 h, and then heated to 750 °C for 3 h. After the reaction was completed, it was cooled and pulverized to 250 mesh to obtain the desired Li-Al-Si-KF composite oxide catalyst.

[0034] The XRD pattern of the oxidation catalyst prepared in this embodiment is attached. Figure 1 As shown, the ore, after processing, forms a LiAlO2-SiO2-KF composite phase. Characteristic peaks of LiAlO2 appear at 2θ values ​​of 22.2 and 33.3, belonging to the (101) and (102) crystal planes respectively; characteristic peaks of SiO2 appear at 22.0 and 28.4, belonging to the (101) and (111) crystal planes respectively; and characteristic peaks of KF appear at 33.4 and 47.9, belonging to the (200) and (220) crystal planes respectively. LiAlO2 serves as the active site for catalytic oxidation, and the Al on the surface... 3+ and O 2- The bond can activate molecular oxygen and adsorb the hydroxyl groups of glycerol molecules, which is the core active center for the oxidation of glycerol to glyceric acid; SiO2, as a framework with a high specific surface area, uniformly disperses the LiAlO2 active phase, avoids the aggregation of active sites, and ensures sufficient contact between active sites and glycerol and oxygen in the reaction; KF can regulate the electronic environment on the catalyst surface, reduce the generation of by-products, and thus improve the selectivity of glyceric acid.

[0035] In this embodiment, glycerol acid is prepared by catalytic oxidation of glycerol using the catalyst prepared above.

[0036] Prepare a glycerol solution with ω%=12.5% ​​according to the raw material ratio of 10g glycerol and 70g pure water. Add 4g of the above catalyst (catalyst to glycerol mass ratio 0.4:1) and mix. Heat the entire reaction system to 80℃ and introduce oxygen at normal pressure (gas flow rate to glycerol molar ratio 50:1) and stir for 24h.

[0037] Example 2 This study uses lithium polymetallic ore from the Vilastow mining area in Keshiketeng Banner, Inner Mongolia Autonomous Region as raw material to prepare an oxidation catalyst, which is then used to catalyze the oxidation of glycerol to prepare glyceric acid.

[0038] The preparation method of the oxidation catalyst described in this embodiment includes the following steps: (1) Raw material pretreatment: Lithium polymetallic ore from the Vilasto mining area (Li2O content 1.71%) in Keshiketeng Banner, Inner Mongolia Autonomous Region, was crushed to 300 mesh, mechanically activated for 4 hours, and the ball-to-material ratio was adjusted to 15:1 and the rotation speed was 150 rpm. (2) Enhanced acid leaching: Add activated mineral powder to 10wt% dilute sulfuric acid solution and mix, adjust the liquid-solid ratio to 8:1, stir and react at 70℃ for 8h, filter and collect the filter residue; (3) Stepwise calcination: Under an inert atmosphere (argon, flow rate of 0.8 L / min), the filter residue was pre-calcined at 350 °C for 3 h, and then heated to 700 °C for 4 h. After the reaction was completed, it was cooled and pulverized to 250 mesh to obtain the desired Li-Al-Si-KF composite oxide catalyst.

[0039] In this embodiment, glycerol acid is prepared by catalytic oxidation of glycerol using the catalyst prepared above.

[0040] Prepare a glycerol solution with ω%=10.0% according to the raw material ratio of 10g glycerol and 90g pure water. Add 3g of the above catalyst (catalyst to glycerol mass ratio of 0.3:1) and mix. Heat the entire reaction system to 70℃ and introduce oxygen at normal pressure (gas flow rate to glycerol molar ratio of 30:1) and stir for 30h.

[0041] Example 3 This study uses lithium polymetallic ore from the Vilastow mining area in Keshiketeng Banner, Inner Mongolia Autonomous Region as raw material to prepare an oxidation catalyst, which is then used to catalyze the oxidation of glycerol to prepare glyceric acid.

[0042] The preparation method of the oxidation catalyst described in this embodiment includes the following steps: (1) Raw material pretreatment: Lithium polymetallic ore from the Vilasto mining area (Li2O content 1.71%) in Keshiketeng Banner, Inner Mongolia Autonomous Region, was crushed to 400 mesh, mechanically activated for 6 hours, and the ball-to-material ratio was adjusted to 20:1 and the rotation speed was 200 rpm. (2) Enhanced acid leaching: Add activated mineral powder to 18wt% phosphoric acid solution and mix, adjust the liquid-solid ratio to 8:1, stir and react at 95℃ for 12h, filter and collect the filter residue; (3) Stepwise calcination: Under an inert atmosphere (argon, flow rate of 1.5 L / min), the filter residue was pre-calcined at 450 °C for 2 h, and then heated to 800 °C for 3 h. After the reaction was completed, it was cooled and pulverized to 250 mesh to obtain the desired Li-Al-Si-KF composite oxide catalyst.

[0043] In this embodiment, glycerol acid is prepared by catalytic oxidation of glycerol using the catalyst prepared above.

[0044] Prepare a glycerol solution with an ω% of 30.0% by mixing raw materials: 30g glycerol and 70g pure water. Add 15g of the above catalyst (catalyst to glycerol mass ratio 0.5:1) and mix. Heat the entire reaction system to 90℃ and introduce oxygen at normal pressure (gas flow rate to glycerol molar ratio 60:1) and stir for 36h.

[0045] Example 4 The preparation method of the oxidation catalyst described in this embodiment is the same as that in Embodiment 1.

[0046] The method for preparing glyceric acid by catalytic oxidation of glycerol in this embodiment is the same as in Example 1, except that a co-catalyst is added to enhance and promote the reaction.

[0047] In this embodiment, the principle of promoting molecular oxygen activation and selective oxidation of glycerol by synergistic interaction between potassium oxalate and the active sites on the surface of the oxidation catalyst is utilized. Specifically, in the catalytic reaction stage described in Example 1, potassium oxalate accounting for 2% of the mass fraction of glycerol is added as a co-catalyst, while the other conditions remain unchanged.

[0048] Comparative Example 1 The preparation method of the oxidation catalyst described in this comparative example is the same as that in Example 1, except that a one-step calcination method is used.

[0049] In the entire preparation method, the raw material pretreatment and enhanced acid leaching are the same as in the original Example 1. During roasting, the filter residue A is directly roasted at 750℃ for 5 hours (the total time is consistent with the original "pre-roasting 2 hours + main roasting 3 hours"). After cooling, it is pulverized to 250 mesh to obtain the catalyst roasted in one step.

[0050] The process of preparing glyceric acid by oxidative catalysis of glycerol using the catalyst prepared above is the same as in Example 1.

[0051] Comparative Example 2 The preparation method of the oxidation catalyst described in this comparative example is the same as that in Example 1, except that the ore raw material is only crushed and not mechanically activated, while the other steps are the same as in Example 1.

[0052] The process of preparing glyceric acid by oxidative catalysis of glycerol using the catalyst prepared above is the same as in Example 1.

[0053] Comparative Example 3 The preparation method of the oxidation catalyst described in this comparative example is the same as that in Example 1, except that the ore raw material is not subjected to acid leaching treatment, and the other steps are the same as in Example 1.

[0054] The process of preparing glyceric acid by oxidative catalysis of glycerol using the catalyst prepared above is the same as in Example 1.

[0055] Comparative Example 4 The preparation method of the oxidation catalyst described in this comparative example is the same as that in Example 4, except that the added co-catalyst is replaced with manganese sulfate, and the other steps are the same as in Example 1.

[0056] The process of preparing glyceric acid by oxidative catalysis of glycerol using the catalyst prepared above is the same as in Example 4.

[0057] Experimental Example 1. Catalytic performance In Examples 1-4 and Comparative Examples 1-4 above, the glycerol conversion rate, glyceric acid selectivity, and glyceric acid yield (conversion rate × selectivity) of the entire catalytic reaction were tested after the glycerol conversion reaction was completed; among them, Glycerol conversion rate = (n 初始 -n 剩余 ) / n 初始 ×100%, which is the molar ratio of glycerol consumed in the reaction to the initial total amount of glycerol; Glyceric acid selectivity = n 生成 / (n 初始 -n 剩余 ) × 100%, which is the molar ratio of glyceric acid produced by the reaction to glycerol consumed in the reaction; Glyceric acid yield = glycerol conversion rate × glyceric acid selectivity.

[0058] The test results are recorded in Table 3 below.

[0059] Table 3 Experimental Results

[0060] It is evident that the oxidation catalyst prepared by the present invention based on low-grade lithium ore as raw material and through a composite pretreatment process including enhanced mechanical activation, high-concentration acid leaching, and high-temperature stepwise roasting can achieve efficient conversion of glycerol to glyceric acid.

[0061] 2. Repeatability This embodiment uses the oxidation catalyst prepared in Example 1 as an example to verify the reusability of the catalyst.

[0062] The catalyst prepared in Example 1 was recovered. The reaction products were collected and separated. After the reaction was complete, the remaining reactants were poured into a Buchner funnel and filtered. The filter residue was the recovered catalyst. This filter residue contained some glycerol solution, glyceric acid, and other glycerol conversion products, requiring washing to remove impurities. It was washed 2-3 times with appropriate amounts of deionized water and anhydrous ethanol. The washed catalyst was then placed in an oven and dried at 80-100°C for 4-6 hours. After drying, it was ground to below 200 mesh for later use.

[0063] The recovered catalyst was directly used in a new round of reaction according to the scheme in Example 1.

[0064] After repeating the catalytic reaction five times, the glycerol conversion rate remained above 55% and the glyceric acid selectivity remained around 60% throughout the entire reaction, indicating that the catalyst has good stability.

[0065] In summary, this invention overcomes the raw material limitations of high-grade lithium ore, has low catalyst preparation cost and is environmentally friendly, and solves the problems of low-grade lithium ore resource utilization and the dependence on precious metals and harsh reaction conditions of existing glycerol oxidation technologies.

[0066] The embodiments of the present invention have been described in detail above. Specific examples have been used to illustrate the principles and implementation methods of the present invention. The description of the above embodiments is only for the purpose of helping to understand the method and core ideas of the present invention. At the same time, for those skilled in the art, there will be changes in the specific implementation methods and application scope based on the ideas of the present invention. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for preparing an oxidation catalyst, characterized in that, Includes the following steps: (1) Low-grade lithium ore is crushed and mechanically activated to obtain activated mineral powder; The low-grade lithium ore contains 1.5%-2.0 wt% Li2O, ≥60 wt% SiO2, and 15-20 wt% Al2O3, and is associated with K2O and F elements. (2) The activated mineral powder is added to acid solution for impregnation and strengthening, and the filter residue is collected by solid-liquid separation; (3) Under a protective atmosphere, the filter residue is pre-calcined at 350-450°C and calcined at 700-800°C to obtain the desired oxidation catalyst.

2. The method for preparing the oxidation catalyst according to claim 1, characterized in that, In step (1), the crushing step includes crushing the low-grade lithium ore to 300-400 mesh.

3. The method for preparing the oxidation catalyst according to claim 2, characterized in that, In step (1), the mechanical activation treatment step includes: The activation treatment step controls the ball-to-material ratio to be 15:1-20:1; and / or, The activation process is performed with the rotation speed controlled at 150-200 rpm; and / or, The activation process is controlled to take 4-6 hours.

4. The method for preparing the oxidation catalyst according to claim 3, characterized in that, In step (2): The acid solution includes a 10-15 wt% dilute sulfuric acid solution or a 12-18% phosphoric acid solution; and / or, The liquid-to-solid mass ratio of the activated mineral powder to the acid solution is 8:1-10:1; and / or, The temperature for the impregnation strengthening step is 70-95℃; and / or, The impregnation and strengthening step takes 8-12 hours.

5. The method for preparing the oxidation catalyst according to any one of claims 1-4, characterized in that, In step (3): The pre-calcination step takes 2-3 hours; and / or, The roasting step takes 3-4 hours; and / or, The protective atmosphere comprises an inert gas with a flow rate of 0.8-1.5 L / min.

6. An oxidation catalyst prepared by the method according to any one of claims 1-5.

7. The application of the oxidation catalyst according to claim 6 in the process of oxidative catalysis to prepare glyceric acid from glycerol.

8. A method for oxidatively catalyzing the preparation of glyceric acid from glycerol, characterized in that, The step includes an oxidation reaction using glycerol and oxygen as raw materials in the presence of the oxidation catalyst described in claim 6.

9. The method for preparing glyceric acid by oxidative catalysis of glycerol according to claim 8, characterized in that: The glycerol has a mass concentration of 10-30 wt%; and / or, The molar ratio of oxygen to glycerol is 30:1 to 60:1, and / or, The mass ratio of the catalyst to glycerol is 0.3:1 to 0.5:1; and / or, The oxidation reaction is carried out at a temperature of 70-90°C; and / or, The oxidation reaction is carried out at atmospheric pressure; and / or, The oxidation reaction takes 24-36 hours.

10. The method for preparing glyceric acid by oxidative catalysis of glycerol according to claim 8 or 9, characterized in that, The method further includes the step of adding a co-catalyst; wherein... The co-catalyst comprises potassium oxalate and / or MnSO4; and / or, The amount of the co-catalyst added accounts for 1-3 wt% of the amount of glycerol used.

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