High-efficiency anti-poisoning pta waste gas oxidation catalyst and preparation method thereof

Abstract

This invention discloses a highly efficient anti-poisoning PTA waste gas oxidation catalyst and its preparation method, relating to the field of industrial waste gas oxidation catalyst technology. The catalyst comprises a manganese-based catalytic oxidation catalyst synthesized by a competitive adsorption impregnation method using soluble transition metal salts, competitive adsorbents, manganese salts, and inert materials as precursors. This achieves a core-shell structured manganese composite oxide active center. The highly stable manganese composite oxide avoids the combination of halogen VOCs decomposition products with active manganese dioxide, ensuring that the catalyst has high catalytic efficiency and excellent stability. The entire process is short, controllable, and produces no waste acid emissions.

Description

Technical Field

[0001] This invention relates to the field of industrial waste gas oxidation catalyst technology, specifically to a highly efficient PTA-resistant waste gas oxidation catalyst and its preparation method. Background Technology

[0002] Emissions of halogenated volatile organic compounds (VOCs) are widespread in industries such as petrochemicals, coal chemicals, and fine chemicals. These compounds are typically highly toxic, difficult to degrade, and challenging to treat; untreated emissions into the atmosphere pose a significant environmental crisis. In PTA production, bromine (Br) is widely used in the liquid-phase catalytic oxidation of paraxylene (PX), but it is usually not effectively recovered and is ultimately emitted into the waste gas. Currently, the treatment of halogenated VOCs has become crucial for air pollution control.

[0003] Under the action of a catalyst, halogenated volatile organic compounds in a gas are completely oxidized by oxygen in the air to carbon dioxide, water, hydrogen halides, or halogen gases. Noble metal catalysts exhibit high activity but are susceptible to poisoning and deactivation; non-noble metal catalysts show strong resistance to halogen poisoning but exhibit low activity for treating alkane-based VOCs. Therefore, the development of halogenated volatile organic compound catalysts should begin with understanding their catalytic mechanism, improving their resistance to poisoning and catalytic activity.

[0004] Currently, most non-precious metal oxidation catalysts have poor stability and low alkane removal performance; while high-performance precious metal catalysts have cost issues. Therefore, there is an urgent need for an oxidation catalyst that can meet the requirements of halogen poisoning resistance and high conversion performance of alkane VOCs. Summary of the Invention

[0005] The technical problem to be solved by this invention is to overcome the shortcomings of the prior art. The purpose is to provide a highly efficient anti-poisoning PTA waste gas oxidation catalyst, which solves the problems of low performance and poisoning of catalysts when removing halogen-containing VOCs, thus providing an economical, environmentally friendly and practical catalyst for the removal of halogen VOCs. This invention applies a manganese precursor and an inert material to the removal of halogen VOCs after coating and calcination. It has good oxidation performance in thermal catalysis and obtains a highly efficient non-precious metal anti-halogen poisoning catalytic oxidation catalyst.

[0006] This invention is achieved through the following technical solution:

[0007] A highly efficient anti-poisoning PTA waste gas oxidation catalyst includes an inert support and an active material. The active material is prepared by competitive adsorption of one or two transition metals and manganese oxides to achieve the composite of transition metal oxides and manganese oxides. The mass percentage of the active material in the catalyst is 15wt% to 50wt%.

[0008] The inert support is an oxide with high specific surface area and thermal stability, and the mass percentage of the inert support in the catalyst is 50wt% to 85wt%.

[0009] The active material forms a manganese composite oxide active center with a core-shell structure by compounding a transition metal oxide with a manganese precursor and an inert carrier material.

[0010] Furthermore, the competitive adsorbents in the competitive adsorption method include two of the following: citric acid, tartaric acid, oxalic acid, lactic acid, and amino acids, mixed in a certain proportion, with a total concentration of 0.5 mol / L to 2 mol / L.

[0011] Furthermore, the inert support is one or two of alumina, molecular sieve, oxygen storage material, titanium dioxide, and zirconium dioxide;

[0012] The manganese precursor is one of manganese carbonate, basic manganese carbonate, and manganese stearate.

[0013] The mass ratio of the manganese precursor to the inert carrier is 1:2 to 2:1.

[0014] A method for preparing a highly efficient anti-poisoning PTA waste gas oxidation catalyst involves dissolving a transition metal precursor in a competitive adsorbent, impregnating it in a mixture of insoluble manganese salt and an inert support, and finally drying and calcining it to obtain the required catalyst powder. The monolithic cordierite honeycomb catalyst is then prepared through a quantitative coating process.

[0015] Furthermore, it also includes the following steps:

[0016] 1) Preparation of competitive adsorbents: Two of the following are selected as competitive adsorbents: citric acid, tartaric acid, oxalic acid, lactic acid and amino acids. They are completely dissolved and mixed to prepare a competitive adsorption solution.

[0017] 2) Dissolution of transition metals: A certain amount of soluble transition metal precursor is added to the competitive adsorption solution, and after complete dissolution, the mixture is stirred continuously until a molten gel is formed.

[0018] 3) Mixing of matrix materials: Weigh a certain amount of insoluble manganese precursor and inert carrier, mechanically stir, and then perform dry ball milling;

[0019] 4) Impregnation of transition metals: A competitive adsorption solution containing soluble salts of transition metals is added to a mixture of manganese precursor and inert support in equal volume for impregnation. The mixture is then dried and calcined to obtain the desired catalyst powder.

[0020] 5) Catalyst coating: The catalyst powder, binder and water are prepared into a suspension with a certain solid content in a certain mass ratio. The mixture is mixed by ball milling and loaded onto a honeycomb carrier by quantitative coating. The mixture is then dried and calcined to obtain the catalyst.

[0021] Further, in step 2), the transition metal soluble salt includes one or two of La, Co, Cu, V, Zr, Nb, Mo, W, and Ce, and the transition metal precursor includes lanthanum acetate, cobalt acetate, copper acetate, vanadium oxalate, ammonium metavanadate, zirconium acetate, niobium oxalate, niobium nitrate, molybdenum acetate, ammonium molybdate, metatungstic acid, ammonium paratungstate, ammonium tungstate, and cerium acetate, with a total concentration of 0.1 mol / L to 0.5 mol / L;

[0022] When two transition metals are added, the molar ratio of the two transition metals is 1:10 to 1:2.

[0023] Furthermore, the amount of the mixed solution of the weighed transition metal and the competing adsorbent is consistent with the water control volume of the matrix material. After impregnation, the drying temperature is 60℃~90℃ and the drying time is 1h~6h. The calcination temperature and time are: calcination at 250℃~400℃ for 1h~3h, followed by calcination at 500℃ for 1h~10h.

[0024] Furthermore, the catalyst and binder are prepared with water as a suspension with a solid content of 30wt% to 45wt%, and the binder is preferably an aqueous solution of boehmite, aluminum sol, silica sol or zircon sol.

[0025] The loading of the catalyst dry-based coating is controlled at 60 g / L to 180 g / L;

[0026] The drying temperature is 50-120℃, the calcination temperature is 450℃-550℃, and the calcination time is 1-5h.

[0027] By using soluble transition metal salts, competitive adsorbents, manganese salts, and inert materials as precursors, a manganese-based catalytic oxidation catalyst was synthesized via a competitive adsorption impregnation method. This resulted in a core-shell structured manganese composite oxide active center. The highly stable manganese composite oxide prevents the combination of halogenated VOCs decomposition products with active manganese dioxide, ensuring high catalytic efficiency and excellent stability. The prepared catalyst exhibits low ignition temperatures for characteristic pollutants in PTA waste gas: ≤250℃ for bromomethane, ≤180℃ for methyl acetate, ≤250℃ for p-xylene, and ≤200℃ for alcohols, ketones, aldehydes, and acids. This meets the application requirements for PTA tail gas treatment; it has the ability to remove sulfur-containing components such as sulfur dioxide, mercaptans, and thioethers, and can completely catalytically purify toxic and harmful organic components in PTA waste gas, including carbon monoxide, aromatic hydrocarbons, alkanes, ethers, alcohols, and esters.

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

[0029] 1. The active substances in this invention are transition metal oxides and manganese and transition metal composite oxides. By combining transition metal oxides with the surface of manganese precursor and inert material, manganese oxides, manganese composite oxides, transition metal oxides and inert materials with core-shell structure are formed. The manganese composite oxides stably remove halogen VOCs, and the corresponding transition metal oxides reduce the chemical adsorption of halogen VOCs products on the surface of catalyst material and manganese oxide. The high efficiency of PTA waste gas catalytic oxidation is achieved by improving thermal stability and anti-halogen poisoning performance.

[0030] 2. This invention uses a competitive adsorption method to prepare manganese composite oxide active centers with a core-shell structure. The highly stable manganese composite oxide avoids the combination of halogen VOCs decomposition products with active manganese dioxide. At the same time, compared with conventional manganese dioxide catalysts, the catalyst preparation process of this invention reduces the amount of nitrate used, generates no wastewater, and has a more green and convenient preparation process. Furthermore, the catalyst has stable catalytic oxidation performance, maintaining a removal rate of over 99% in long-term halogen VOCs catalytic oxidation. Attached Figure Description

[0031] The accompanying drawings, which are included to provide a further understanding of embodiments of the invention and form part of this application, do not constitute a limitation thereof. In the drawings:

[0032] Figure 1 This is a graph showing the catalyst performance test in Example 1 of the present invention;

[0033] Figure 2 This is a graph showing the catalyst performance test in Example 2 of the present invention;

[0034] Figure 3 This is a graph showing the catalyst performance test in Example 3 of the present invention;

[0035] Figure 4 This is a graph showing the catalyst performance test in Example 4 of the present invention;

[0036] Figure 5 This is a graph showing the catalyst performance test in Example 5 of the present invention;

[0037] Figure 6 This is a graph showing the performance test of the catalyst in Comparative Example 1 of the present invention;

[0038] Figure 7 This is a graph showing the performance test of the catalyst in Comparative Example 2 of the present invention. Detailed Implementation

[0039] To make the objectives, technical solutions, and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the embodiments and accompanying drawings. The illustrative embodiments and descriptions of the present invention are only used to explain the present invention and are not intended to limit the present invention.

[0040] Example 1

[0041] Preparation of competitive adsorbent: Weigh 1 mol of citric acid and 0.5 mol of tartaric acid, mix and dissolve in 1 L of deionized water.

[0042] Dissolution of transition metals: Weigh 0.1 mol of lanthanum acetate and add it to the competitive adsorbent solution. Stir at room temperature until completely dissolved, then heat to 60℃ and stir for 60 min.

[0043] Mixing of matrix materials: Take 500g of manganese carbonate and 500g of alumina with high specific surface area, stir mechanically for 0.5h, and then ball mill for 20min with a zirconia ball-to-material ratio of 2.

[0044] Impregnation of transition metals: Weigh 1L of the transition metal-competitive adsorbent mixed solution, add 1000g of matrix material for medium-volume impregnation, mix evenly, and dry at 90℃ for 1h; calcine at 250℃ for 1h, then calcine at 500℃ for 1h. The desired catalyst powder of Example 3 is prepared.

[0045] Catalyst coating: Weigh 500g of catalyst powder from Example 1, 30g of boehmite, 50g of silica sol aqueous solution, and 1000g of deionized water, and mix them by ball milling to prepare a catalyst slurry. Coat 180g of the solid material onto 1L of 400-mesh honeycomb carrier, dry at 100℃ to constant weight, and then calcine at 500℃ for 3 hours to obtain the high-efficiency anti-poisoning PTA waste gas oxidation catalyst described in this example.

[0046] Figure 1 For the catalyst performance in this embodiment, methyl acetate T 99 =180℃, Acetic Acid T 99 =190℃, xylene T 99 =240℃, bromomethane T 99 =230℃.

[0047] Example 2

[0048] Preparation of competitive adsorbent: Weigh 0.25 mol of citric acid and 0.25 mol of oxalic acid, mix and dissolve in 0.5 L of deionized water.

[0049] Dissolution of transition metals: Weigh 0.1 mol ammonium metavanadate and 0.01 mol zirconium acetate and add them to the competitive adsorbent solution. Stir at room temperature until completely dissolved, then heat to 80℃ and stir for 60 min.

[0050] Mixing of matrix materials: Take 800g of manganese carbonate and 500g of titanium dioxide with high specific surface area, stir mechanically for 1 hour, and then ball mill for 30 minutes with a zirconium oxide ball-to-material ratio of 2.

[0051] Impregnation of transition metals: Weigh 0.5 L of the transition metal-competitive adsorbent mixed solution, add 1000 g of matrix material for medium-volume impregnation, mix evenly, and dry at 80 °C for 2 h; calcine at 400 °C for 1 h, then calcine at 500 °C for 1 h. The desired catalyst powder of Example 4 is prepared.

[0052] Catalyst coating: Weigh the catalyst powder from Example 2, 50g of zirconium sol aqueous solution, 50g of silica sol aqueous solution, and 1000g of deionized water, and mix them by ball milling to prepare a catalyst slurry. Coat 100g of solid material onto 1L of 400-mesh honeycomb carrier, dry it at 120℃ to constant weight, and then calcine it at 500℃ for 1h to obtain the high-efficiency anti-poisoning PTA waste gas oxidation catalyst described in this example.

[0053] Figure 2 For the catalyst performance in this embodiment, methyl acetate T 99 =170℃, Acetic Acid T 99 =200℃, xylene T 99 =230℃, bromomethane T 99 =250℃.

[0054] Example 3

[0055] Preparation of competitive adsorbent: Weigh 0.5 mol of oxalic acid and 0.5 mol of amino acids, mix and dissolve in 1 L of deionized water.

[0056] Dissolution of transition metals: Weigh 0.1 mol niobium oxalate and 0.4 mol ammonium molybdate and add them to the competitive adsorbent solution. Stir at room temperature until completely dissolved, then heat to 90℃ and stir for 30 min.

[0057] Mixing of matrix materials: Take 300g of basic manganese carbonate and 800g of zirconium dioxide with high specific surface area, stir mechanically for 1 hour, and then ball mill for 60 minutes with a zirconium oxide ball-to-material ratio of 2.

[0058] Impregnation of transition metals: Weigh 0.4 L of the transition metal-competitive adsorbent mixed solution, add 1000 g of matrix material for medium-volume impregnation, mix thoroughly, and dry at 60 °C for 5 h; calcine at 250 °C for 1 h, then calcine at 500 °C for 2 h. The desired catalyst powder of Example 5 is prepared.

[0059] Catalyst coating: Weigh 500g of catalyst powder from Example 3, 50g of zirconium sol aqueous solution, and 1000g of deionized water, and mix them by ball milling to prepare a catalyst slurry. Apply a quantitative amount of 180g of solid material to 1L of 200-mesh honeycomb carrier, dry it at 120℃ to constant weight, and then calcine it at 550℃ for 1h to obtain the high-efficiency anti-poisoning PTA waste gas oxidation catalyst described in this example.

[0060] Figure 3 For the catalyst performance in this embodiment, methyl acetate T 99 =180℃, Acetic Acid T 99 =170℃, xylene T 99 =250℃, bromomethane T 99 =250℃.

[0061] Example 4

[0062] Preparation of competitive adsorbent: Weigh 0.8 mol of citric acid and 0.14 mol of oxalic acid, mix and dissolve in 1 L of deionized water.

[0063] Dissolution of transition metals: Weigh 0.4 mol cobalt acetate and 0.071 mol ammonium metatungstate and add them to the competitive adsorbent solution. Stir at room temperature until completely dissolved, then heat to 90℃ and stir for 30 min.

[0064] Mixing of matrix materials: Take 800g of basic manganese carbonate and 500g of oxygen storage material with high specific surface area, stir mechanically for 1 hour, and then ball mill for 60 minutes with a zirconia ball-to-material ratio of 2.

[0065] Impregnation of transition metals: Weigh 0.4 L of the transition metal-competitive adsorbent mixed solution, add 1000 g of matrix material for medium-volume impregnation, mix evenly, and dry at 60 °C for 5 h; calcine at 250 °C for 1 h, then calcine at 500 °C for 1 h. The desired catalyst powder of Example 5 is prepared.

[0066] Catalyst coating: Weigh 500g of catalyst powder from Example 4, 50g of aluminum sol aqueous solution, and 1000g of deionized water, and mix them by ball milling to prepare a catalyst slurry. Coat 120g of solid material onto 1L of 200-mesh honeycomb carrier, dry at 120℃ to constant weight, and then calcine at 550℃ for 1h to obtain the high-efficiency anti-poisoning PTA waste gas oxidation catalyst described in this example.

[0067] Figure 4 For the catalyst performance in this embodiment, methyl acetate T 99 =170℃, Acetic Acid T 99 =170℃, xylene T 99 =230℃, bromomethane T 99 =250℃.

[0068] Example 5

[0069] Preparation of competitive adsorbent: Weigh 0.25 mol of oxalic acid and 1 mol of lactic acid, mix and dissolve in 1 L of deionized water.

[0070] Dissolution of transition metals: Weigh 0.1 mol of cerium acetate and 0.4 mol of copper acetate and add them to the competitive adsorbent solution. Stir at room temperature until completely dissolved, then heat to 90℃ and stir for 30 min.

[0071] Mixing of matrix materials: Take 800g of basic manganese carbonate and 500g of low silica-alumina molecular sieve with high specific surface area, stir mechanically for 1 hour, and then ball mill for 60 minutes with a zirconia ball-to-material ratio of 2.

[0072] Impregnation of transition metals: Weigh 0.4 L of the transition metal-competitive adsorbent mixed solution, add 1000 g of matrix material for medium-volume impregnation, mix evenly, and dry at 60 °C for 5 h; calcine at 400 °C for 1 h, then calcine at 500 °C for 1 h. The desired catalyst powder of Example 5 is prepared.

[0073] Catalyst coating: Weigh 500g of catalyst powder from Example 5, 50g of silica sol aqueous solution, and 1000g of deionized water, and mix them by ball milling to prepare a catalyst slurry. Coat 180g of solid material onto 1L of 200-mesh honeycomb carrier, dry at 120℃ to constant weight, and then calcine at 550℃ for 1h to obtain the high-efficiency anti-poisoning PTA waste gas oxidation catalyst described in this example.

[0074] Figure 5 For the catalyst performance in this embodiment, methyl acetate T 99 =180℃, Acetic Acid T 99 =190℃, xylene T 99 =220℃, bromomethane T 99 =220℃.

[0075] Comparative Example 1

[0076] The following is Comparative Example 1 and its appendix. Figure 6 The selection of catalyst transition metal, the type and proportion of matrix material, and the catalyst coating method in this comparative example are completely the same as in Example 1, but no competing adsorbent is added:

[0077] Dissolution of transition metals: Weigh 0.1 mol of lanthanum acetate and add it to the competitive adsorbent solution. Stir at room temperature until completely dissolved, then heat to 60℃ and stir for 60 min.

[0078] Mixing of matrix materials: Take 500g of manganese carbonate and 500g of alumina with high specific surface area, stir mechanically for 0.5h, and then ball mill for 20min with a zirconia ball-to-material ratio of 2.

[0079] Impregnation of transition metal: Weigh 1L of transition metal solution and add it to 1000g of matrix material for impregnation. After mixing evenly, dry at 90℃ for 1h; calcine at 250℃ for 1h, then at 500℃ for 1h. The desired catalyst powder of Comparative Example 1 is thus prepared.

[0080] Catalyst coating: Weigh 500g of catalyst powder from Comparative Example 1, 30g of boehmite, 50g of silica sol aqueous solution, and 1000g of deionized water, and mix them by ball milling to prepare a catalyst slurry. Apply 180g of the solid material to 1L of 400-mesh honeycomb carrier, dry at 100℃ to constant weight, and then calcine at 500℃ for 3h to obtain the catalyst from Comparative Example 1.

[0081] Figure 6 For the catalyst performance of Comparative Example 1, methyl acetate T was used. 99 =180℃, Acetic Acid T 99 =190℃, xylene T 99 =250℃, bromomethane T 99 =300℃.

[0082] Comparative Example 2

[0083] The following is Comparative Example 2 and its appendix. Figure 7 The catalyst competing adsorbent, transition metal, matrix material type and ratio, and catalyst coating method in this comparative example are completely the same as in Example 2, except that soluble manganese acetate is used as the manganese precursor.

[0084] Preparation of competitive adsorbent: Weigh 0.25 mol of citric acid and 0.25 mol of oxalic acid, mix and dissolve in 0.5 L of deionized water.

[0085] Dissolution of transition metals: Weigh 0.1 mol ammonium metavanadate and 0.01 mol zirconium acetate and add them to the competitive adsorbent solution. Stir at room temperature until completely dissolved, then heat to 80℃ and stir for 60 min.

[0086] Mixing of matrix materials: Take 500g of manganese acetate and 500g of titanium dioxide with high specific surface area, stir mechanically for 1 hour, and then ball mill for 30 minutes with a zirconia ball-to-material ratio of 2.

[0087] Impregnation of transition metals: Weigh 0.5 L of the transition metal-competitive adsorbent mixed solution, add 1000 g of matrix material for medium-volume impregnation, mix evenly, and dry at 80 °C for 2 h; calcine at 400 °C for 1 h, then calcine at 500 °C for 1 h. The desired catalyst powder of Comparative Example 2 is prepared.

[0088] Catalyst coating: Weigh the catalyst powder of Comparative Example 2, 50g of zirconium sol aqueous solution, 50g of silica sol aqueous solution, and 1000g of deionized water, and mix them by ball milling to prepare a catalyst slurry. Coat 100g of solid material onto 1L of 400-mesh honeycomb carrier, dry it at 120℃ to constant weight, and then calcine it at 500℃ for 1h to obtain Comparative Example 2.

[0089] Figure 7 For the catalyst performance of Comparative Example 2, methyl acetate T 99 =290℃, Acetic Acid T 99 =220℃, xylene T 99 =320℃, bromomethane T 99 =230℃.

[0090] The specific embodiments described above further illustrate the purpose, technical solution, and beneficial effects of the present invention. It should be understood that the above description is only a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A catalyst for oxidizing PTA-poisoned waste gas, characterized in that, The catalyst comprises an inert support and an active material, wherein the active material is prepared by competitive adsorption of one or two transition metals and manganese oxides, thereby achieving a composite of transition metal oxides and manganese oxides. The active material accounts for 15 wt% to 50 wt% of the mass of the catalyst. The inert support is an oxide with high specific surface area and thermal stability, and the inert support accounts for 50wt%~85wt% of the mass of the catalyst. The active material forms a manganese composite oxide active center with a core-shell structure by compounding a transition metal oxide with a manganese precursor and an inert carrier material. The competitive adsorbents in the competitive adsorption method include two of the following: citric acid, tartaric acid, oxalic acid, lactic acid, and amino acids, mixed in a certain proportion, with a total concentration of 0.5 mol / L to 2 mol / L. The manganese precursor is an insoluble manganese salt, including one of manganese carbonate, basic manganese carbonate, and manganese stearate. The mass ratio of the manganese precursor to the inert carrier is 1:2 to 2:

1.

2. The anti-poisoning PTA waste gas oxidation catalyst according to claim 1, characterized in that, The inert carrier is an oxygen storage material.

3. The anti-poisoning PTA waste gas oxidation catalyst according to claim 1, characterized in that, The inert support is one or two of alumina, molecular sieve, titanium dioxide, and zirconium dioxide.

4. A method for preparing an anti-poisoning PTA waste gas oxidation catalyst according to any one of claims 1-3, characterized in that, The catalyst powder is prepared by dissolving transition metal precursors in a competitive adsorbent and impregnating them in a mixture of insoluble manganese salt and inert support. After drying and calcination, the desired catalyst powder is obtained. The monolithic cordierite honeycomb catalyst is then prepared through a quantitative coating process.

5. The method for preparing an anti-poisoning PTA waste gas oxidation catalyst according to claim 4, characterized in that, Includes the following steps: 1) Preparation of competitive adsorbents: Two of the following are selected as competitive adsorbents: citric acid, tartaric acid, oxalic acid, lactic acid and amino acids. They are completely dissolved and mixed to prepare a competitive adsorption solution. 2) Dissolution of transition metals: A certain amount of soluble transition metal precursor is added to the competitive adsorption solution, and after complete dissolution, the mixture is stirred continuously until a sol is formed; 3) Mixing of matrix materials: Weigh a certain amount of insoluble manganese precursor and mechanically stir it with an inert carrier, and then perform dry ball milling; 4) Impregnation of transition metals: An equal volume of manganese precursor and inert support mixture is added to a competitive adsorption solution containing soluble salts of transition metals for impregnation. The mixture is then dried and calcined to obtain the desired catalyst powder. 5) Catalyst coating: The catalyst powder, binder and water are prepared into a suspension with a certain solid content in a certain mass ratio. The mixture is mixed by ball milling and loaded onto a honeycomb carrier by quantitative coating. The mixture is then dried and calcined to obtain the catalyst.

6. The method for preparing an anti-poisoning PTA waste gas oxidation catalyst according to claim 5, characterized in that, The soluble transition metal in step 2) includes one or two of La, Co, Cu, V, Zr, Nb, Mo, W, and Ce, and the transition metal precursor includes lanthanum acetate, cobalt acetate, copper acetate, vanadium oxalate, ammonium metavanadate, zirconium acetate, niobium oxalate, niobium nitrate, molybdenum acetate, ammonium molybdate, metatungstic acid, ammonium paratungstate, ammonium tungstate, and cerium acetate, with a total concentration of 0.1 mol / L to 0.5 mol / L. When two transition metals are added, the molar ratio of the two transition metals is 1:10 to 1:

2.

7. The method for preparing an anti-poisoning PTA waste gas oxidation catalyst according to claim 4, characterized in that, After impregnation, the drying temperature is 60℃~90℃ and the drying time is 1h~6h; the calcination temperature and time are: calcination at 250℃~400℃ for 1h~3h, followed by calcination at 500℃ for 1h~10h.

8. The method for preparing an anti-poisoning PTA waste gas oxidation catalyst according to claim 4, characterized in that, The catalyst and binder are prepared with water to form a suspension with a solid content of 30wt%~45wt%, and the binder is an aqueous solution of boehmite, aluminum sol, silica sol or zircon sol. The loading of the catalyst dry-based coating is controlled at 60 g / L~180 g / L; The drying temperature is 50-120℃, the calcination temperature is 450℃-550℃, and the calcination time is 1-5h.

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