Arsenic-poisoning-resistant denitration catalyst and preparation method thereof

Abstract

The present application relates to the technical field of denitration catalyst, in particular to an arsenic-poisoning-resistant denitration catalyst and a preparation method thereof.The arsenic-poisoning-resistant denitration catalyst comprises a composite carrier, an active component and a catalyst promoter, the mass ratio of the active component to the composite carrier is (3-8):100, and the mass ratio of the catalyst promoter to the composite carrier is (2-10):100;the composite carrier comprises anatase TiO2, porous active calcium silicate and modified nano zinc oxide;the active component comprises vanadium oxide, neodymium oxide and yttrium oxide;and the catalyst promoter comprises molybdenum oxide, cerium oxide and nickel oxide.The arsenic-poisoning-resistant denitration catalyst can efficiently inhibit the poisoning of arsenic and alkali metals on the catalyst, can maintain excellent denitration activity in a complex flue gas environment for a long time, and can be widely applied to coal-fired power plants, biomass boilers, steel industries and the like.

Description

Technical Field

[0001] This invention relates to the field of denitrification catalyst technology, and in particular to an arsenic-resistant denitrification catalyst and its preparation method. Background Technology

[0002] In industrial processes such as coal-fired power plants, flue gas contains large amounts of nitrogen oxides (NOx), posing a serious threat to the atmospheric environment. Therefore, developing highly efficient denitrification catalysts is crucial for reducing NOx emissions. However, traditional denitrification catalysts are often poisoned by arsenic when treating arsenic-containing flue gas, leading to decreased catalytic activity and shortened lifespan. For example, if the mass fraction of arsenic in coal exceeds 3 × 10⁻⁶... -6 The lifespan of SCR catalysts will be reduced by about 30%. Therefore, developing a highly efficient denitrification catalyst resistant to arsenic poisoning has become an urgent problem to be solved. Summary of the Invention

[0003] The first objective of this invention is to provide an arsenic-poisoning-resistant denitrification catalyst, which not only possesses highly efficient denitrification performance but also excellent resistance to arsenic poisoning. The second objective of this invention is to provide a method for preparing the arsenic-poisoning-resistant catalyst.

[0004] The present invention provides an anti-arsenic poisoning catalyst, comprising a composite support, an active component and a co-catalyst, wherein the mass ratio of the active component to the composite support is (3-8):100, and the mass ratio of the co-catalyst to the composite support is (2-10):100.

[0005] The composite carrier includes anatase TiO2, porous active calcium silicate, and modified nano zinc oxide;

[0006] The active components include vanadium oxide, neodymium oxide, and yttrium oxide;

[0007] The cocatalysts include molybdenum oxide, cerium oxide, and nickel oxide.

[0008] Preferably, the mass ratio of anatase TiO2, porous active calcium silicate, and modified nano zinc oxide in the composite carrier is 100:(1-5):(1-3).

[0009] Preferably, the mass ratio of vanadium oxide, neodymium oxide, and yttrium oxide in the active component is 10:(1-8):(0.5-5).

[0010] Preferably, the mass ratio of molybdenum oxide, cerium oxide, and nickel oxide in the co-catalyst is 10:(2-8):(0.1-3).

[0011] This invention provides a method for preparing an arsenic poisoning resistant catalyst, comprising the following steps:

[0012] (1) Calcium silicate powder, chitosan, stearic acid and carboxymethyl cellulose are added to a reaction vessel in a mass ratio of 100:(1-4):(0.5-2):(0.1-0.5). After stirring at 120-150℃, the mixture is kept at the temperature for 120-180 minutes, then rapidly cooled. After precipitation, the mixture is dried at 60-80℃, calcined at 400-600℃, and ground to 120-180 mesh to obtain porous active calcium silicate.

[0013] (2) The dried nano zinc oxide powder, anhydrous ethanol, and rare earth coupling agent are mixed and stirred for 1-3 hours at a mass ratio of 100:(60-90):(2-6). Then, a 5% cerium nitrate solution is slowly added and stirred evenly. After filtration, drying, and grinding to 120-180 mesh, modified nano zinc oxide is obtained.

[0014] (3) Thoroughly mix anatase TiO2, porous active calcium silicate and modified nano zinc oxide to obtain a composite carrier;

[0015] (4) Add the mixed solution of the active component precursor salt to the composite carrier and mix for 2-5 hours. Add the surface dispersant and mix for 1-2 hours. Add the mixed solution of the catalyst precursor salt and mix for 2-5 hours. Add the molding aid and mix evenly. After aging, extrusion, drying and calcination, the arsenic poisoning denitrification catalyst is obtained.

[0016] Preferably, the molar mass ratio of zinc to cerium in step (2) is 100:(1-5).

[0017] Preferably, the surface dispersant in step (4) is at least one of polysulfonic acid, sodium dodecylbenzenesulfonate, and dodecyl acetic acid.

[0018] Preferably, the mass ratio of the surface dispersant to the composite carrier is (0.3-2):100.

[0019] Preferably, the molding aid in step (4) is at least one of glass fiber, carboxymethyl cellulose, amino cellulose, and liquid paraffin; the mass ratio of the molding aid to the composite carrier is (0.3-3):100.

[0020] Preferably, in step (4), the aging temperature is 20-35℃ and the aging time is 24-72h; the drying temperature is 40-75℃ and the drying time is 30-65h; the calcination temperature is 500-630℃ and the calcination time is 12-40h.

[0021] In summary, compared with the prior art, the present invention has the following advantages:

[0022] The denitrification catalyst provided by the technical solution of the present invention includes a composite support, an active component, and a co-catalyst. Among them, (1) the synergistic effect of anatase TiO2, porous active calcium silicate, and modified nano zinc oxide can inhibit the adsorption and oxidation of As2O3 on the catalyst surface, inhibit the accumulation of As2O5 on the catalyst surface, and improve the catalyst's resistance to arsenic poisoning; (2) porous active calcium silicate and modified nano zinc oxide can preferentially capture arsenic on the catalyst or active component, solidify it, and inhibit the poisoning effect of arsenic on the catalyst; (3) the efficient synergy of porous active calcium silicate and modified nano zinc oxide can effectively inhibit the adsorption of alkali metals on the catalyst surface, inhibit the deposition of alkali metal ions on the catalyst surface, and also increase the alkali metal capacity of the catalyst, thereby improving the catalyst's resistance to alkali metal poisoning; (4) the optimized combination of the active component and the co-catalyst exhibits the best catalytic activity and good resistance to alkali metals.

[0023] The denitrification catalyst provided by this invention can effectively inhibit the poisoning of the catalyst by arsenic and alkali metals, maintain excellent denitrification activity in complex flue gas environments, and can be widely used in coal-fired power plants, biomass boilers, steel industry, etc. Detailed Implementation

[0024] It should be noted that the following detailed descriptions are illustrative and intended to provide further explanation of this application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains.

[0025] It should be noted that the terminology used herein is for the purpose of describing particular implementations only and is not intended to limit the exemplary implementations according to this application. As used herein, the singular form includes the plural form unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this description, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.

[0026] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0027] Example 1

[0028] An anti-arsenic poisoning catalyst includes a composite support, an active component, and a co-catalyst, wherein the mass ratio of the active component to the composite support is 3:50, and the mass ratio of the co-catalyst to the composite support is 2:25.

[0029] The composite carrier is made of anatase TiO2, porous active calcium silicate and modified nano zinc oxide in a mass ratio of 100:3:1.5.

[0030] The active components are vanadium oxide, neodymium oxide and yttrium oxide, with a mass ratio of 5:3:1.

[0031] The co-catalyst is composed of molybdenum oxide, cerium oxide, and nickel oxide, with a mass ratio of 10:7:0.5.

[0032] The preparation method of the above-mentioned anti-arsenic poisoning denitrification catalyst is as follows:

[0033] (1) Calcium silicate powder, cationic chitosan, stearic acid and carboxymethyl cellulose were added to a deionized water solution in a mass ratio of 100:2:1.5:0.3 in an autoclave. The mixture was stirred evenly at 135°C and kept at the temperature for 130 min. After rapid cooling and full precipitation, the mixture was dried at 72°C, calcined at 510°C, and ground to 160 mesh to obtain porous active calcium silicate powder.

[0034] (2) The dried nano zinc oxide powder, anhydrous ethanol, and rare earth coupling agent WG-1 were added to a beaker at a mass ratio of 100:76:3. The mixture was stirred under ultrasonic conditions at 80 Hz for 1.5 h. Then, a 5% cerium nitrate solution was slowly added, wherein the molar mass ratio of zinc to cerium was 100:3.8. After stirring evenly, the mixture was filtered, dried at 55 ℃, and ground to 145 mesh to obtain modified nano zinc oxide powder.

[0035] (3) The anatase mesoporous TiO2, porous active calcium silicate and modified nano zinc oxide were thoroughly mixed to obtain a composite carrier;

[0036] (4) The mixed solution of the active component precursor salt dissolved in deionized water was added to the composite carrier and mixed for 2.5 h. Then, a surface dispersant was added (in this embodiment, the surface dispersant is polysulfonic acid, sodium dodecylbenzenesulfonate and dodecyl acetic acid, with a mass ratio of 1:1:1). The mass ratio of the surface dispersant to the composite carrier was 1.3%. The mixture was mixed for 1.5 h. Then, a mixed solution of the co-catalyst precursor salt dissolved in deionized water was added and mixed for 3.5 h. Then, a molding aid was added (in this embodiment, the molding aid is a combination of glass fiber, carboxymethyl cellulose, amino cellulose and liquid paraffin, with a mass ratio of 10:1:1:1). The mass ratio of the molding aid to the composite carrier was 2.1%. After uniform mixing, the mixture was aged at 28 °C for 32 h, extruded, dried at 62 °C for 58 h, and finally calcined at 530 °C for 36 h to obtain the anti-arsenic poisoning denitrification catalyst.

[0037] The active precursor salts are vanadium salts, neodymium salts, and yttrium salts commonly used in the field, such as ammonium metavanadate, neodymium chloride, and yttrium acetate.

[0038] The co-catalyst salt is a molybdenum salt, cerium salt, or nickel salt used in the art, such as ammonium molybdate, cerium nitrate, or nickel nitrate.

[0039] Example 2

[0040] An anti-arsenic poisoning denitrification catalyst includes a composite support, an active component, and a co-catalyst, wherein the mass ratio of the active component to the composite support is 1:20, and the mass ratio of the co-catalyst to the composite support is 3:100.

[0041] The composite carrier is a mixture of anatase TiO2, porous active calcium silicate and modified nano zinc oxide, with a mass ratio of 50:2:1.

[0042] The active components are vanadium oxide, neodymium oxide and yttrium oxide, with a mass ratio of 5:1:2.

[0043] The co-catalyst is composed of molybdenum oxide, cerium oxide, and nickel oxide, with a mass ratio of 10:3:2.

[0044] The preparation method of the above-mentioned anti-arsenic poisoning denitrification catalyst is as follows:

[0045] (1) Calcium silicate powder, chitosan, stearic acid and carboxymethyl cellulose were added to a deionized water solution in a mass ratio of 100:3:1:0.3 in an autoclave. The mixture was stirred evenly at 145°C and kept at the temperature for 160 min. After rapid cooling and full precipitation, the mixture was dried at 65°C, calcined at 580°C, and ground to 130 mesh to obtain porous active calcium silicate powder.

[0046] (2) The dried nano zinc oxide powder, anhydrous ethanol, and rare earth coupling agent WG-1 were added to a beaker at a mass ratio of 100:82:4.5. The mixture was stirred under ultrasonic conditions at 80 Hz for 2 hours. Then, a 5% cerium nitrate solution was slowly added, wherein the molar mass ratio of zinc to cerium was 100:1.8. After stirring evenly, the mixture was filtered, dried at 55 ℃, and ground to 160 mesh to obtain modified nano zinc oxide powder.

[0047] (3) The anatase mesoporous TiO2, porous active calcium silicate and modified nano zinc oxide were thoroughly mixed to obtain a composite carrier;

[0048] (4) The active component precursor salt was dissolved in deionized water to make a mixed solution and added to the composite carrier. After mixing for 2 hours, the surface dispersant dodecyl acetic acid was added. The mass ratio of the surface dispersant to the composite carrier was 1.6%. After mixing for 1 hour, the co-catalyst precursor salt was added in a mixed solution dissolved in deionized water and mixed for 2 hours. The molding aid glass fiber was added. The mass ratio of the molding aid to the composite carrier was 0.8%. After mixing evenly, the mixture was aged at 32°C for 65 hours, extruded, dried at 70°C for 32 hours, and finally calcined at 580°C for 12 hours to obtain the anti-arsenic poisoning denitrification catalyst.

[0049] Example 3

[0050] An anti-arsenic poisoning denitrification catalyst includes a composite support, an active component, and a co-catalyst, wherein the mass ratio of the active component to the composite support is 1:25, and the mass ratio of the co-catalyst to the composite support is 9:100.

[0051] The composite carrier is made of anatase TiO2, porous active calcium silicate and modified nano zinc oxide in a mass ratio of 100:5:1.

[0052] The active components are vanadium oxide, neodymium oxide and yttrium oxide, with a mass ratio of 10:4:3.

[0053] The co-catalyst is composed of molybdenum oxide, cerium oxide, and nickel oxide, with a mass ratio of 10:8:0.5.

[0054] The preparation method of the above-mentioned anti-arsenic poisoning denitrification catalyst is as follows:

[0055] (1) Calcium silicate powder, chitosan, stearic acid and carboxymethyl cellulose were added to a deionized water solution in a mass ratio of 100:1.5:0.8:0.2 in an autoclave. The mixture was stirred evenly at 138°C and kept at 138 min. After rapid cooling and full precipitation, the mixture was dried at 78°C, calcined at 460°C, and ground to 140 mesh to obtain porous active calcium silicate powder.

[0056] (2) The dried nano zinc oxide powder, anhydrous ethanol, and rare earth coupling agent WG-1 were added to a beaker at a mass ratio of 100:66:2.3. The mixture was stirred under ultrasonic conditions at 80 Hz for 1.6 h. Then, a 5% cerium nitrate solution was slowly added, wherein the molar mass ratio of zinc to cerium was 100:4.5. After stirring evenly, the mixture was filtered, dried at 51 ℃, and ground to 170 mesh to obtain modified nano zinc oxide powder.

[0057] (3) The anatase mesoporous TiO2, porous active calcium silicate and modified nano zinc oxide were thoroughly mixed to obtain a composite carrier;

[0058] (4) The active component precursor salt was dissolved in deionized water to make a mixed solution and added to the composite carrier. After mixing for 5 hours, polysulfonic acid was added as a surface dispersant. The mass ratio of the surface dispersant to the composite carrier was 0.3%. After mixing for 2 hours, a mixed solution of the catalyst precursor salt was added as a co-catalyst and dissolved in deionized water. After mixing for 5 hours, aminocellulose was added as a molding aid. The mass ratio of the molding aid to the composite carrier was 1.8%. After mixing evenly, the mixture was aged at 26°C for 45 hours, extruded, dried at 68°C for 45 hours, and finally calcined at 510°C for 40 hours to obtain the arsenic poisoning denitrification catalyst.

[0059] Example 4

[0060] An anti-arsenic poisoning denitrification catalyst includes a composite support, an active component, and a co-catalyst, wherein the mass ratio of the active component to the composite support is 3:100, and the mass ratio of the co-catalyst to the composite support is 1:50.

[0061] The composite carrier is made of anatase TiO2, porous active calcium silicate and modified nano zinc oxide in a mass ratio of 100:1:1.

[0062] The active components are vanadium oxide, neodymium oxide and yttrium oxide, with a mass ratio of 10:1:0.5.

[0063] The co-catalyst is composed of molybdenum oxide, cerium oxide, and nickel oxide, with a mass ratio of 10:2:0.1.

[0064] The preparation method of the above-mentioned anti-arsenic poisoning denitrification catalyst is as follows:

[0065] (1) Calcium silicate powder, chitosan, stearic acid and carboxymethyl cellulose were added to a deionized water solution in a mass ratio of 100:1:0.5:0.1 in an autoclave. The mixture was stirred evenly at 120°C and kept at the temperature for 120 min. After rapid cooling and full precipitation, the mixture was dried at 60°C, calcined at 400°C, and ground to 120 mesh to obtain porous active calcium silicate powder.

[0066] (2) The dried nano zinc oxide powder, anhydrous ethanol, and rare earth coupling agent WG-1 were added to a beaker at a mass ratio of 50:30:1. The mixture was stirred under ultrasonic conditions at 80 Hz for 1 h. Then, a 5% cerium nitrate solution was slowly added, wherein the molar mass ratio of zinc to cerium was 100:5. After stirring evenly, the mixture was filtered, dried at 40 ℃, and ground to 120 mesh to obtain modified nano zinc oxide powder.

[0067] (3) The anatase mesoporous TiO2, porous active calcium silicate and modified nano zinc oxide were thoroughly mixed to obtain a composite carrier;

[0068] (4) The active component precursor salt is dissolved in deionized water to make a mixed solution and added to the composite carrier. After mixing for 3 hours, a surface dispersant is added (in this example, the surface dispersant is a combination of polysulfonic acid and dodecyl acetic acid, with a mass ratio of 1:1). The mass ratio of the surface dispersant to the composite carrier is 0.7%. After mixing for 1.8 hours, a co-catalyst precursor salt is dissolved in deionized water to make a mixed solution and mixed for 2 hours. A molding aid, glass fiber, is added. The mass ratio of the molding aid to the composite carrier is 0.3%. After mixing evenly, the mixture is aged at 20°C for 24 hours, extruded, dried at 40°C for 30 hours, and finally calcined at 500°C for 32 hours to obtain the anti-arsenic poisoning denitrification catalyst.

[0069] Example 5

[0070] An anti-arsenic poisoning denitrification catalyst includes a composite support, an active component, and a co-catalyst, wherein the mass ratio of the active component to the composite support is 2:25, and the mass ratio of the co-catalyst to the composite support is 1:10.

[0071] The composite carrier is a mixture of anatase TiO2, porous active calcium silicate and modified nano zinc oxide, with a mass ratio of 100:5:3.

[0072] The active components are vanadium oxide, neodymium oxide and yttrium oxide, with a mass ratio of 10:8:5.

[0073] The co-catalyst is composed of molybdenum oxide, cerium oxide, and nickel oxide, with a mass ratio of 10:8:3.

[0074] The preparation method of the above-mentioned anti-arsenic poisoning denitrification catalyst is as follows:

[0075] (1) Calcium silicate powder, chitosan, stearic acid and carboxymethyl cellulose were added to a deionized water solution in a mass ratio of 100:4:2:0.5 in an autoclave. The mixture was stirred evenly at 150°C and kept at 180 min. After rapid cooling and full precipitation, the mixture was dried at 80°C, calcined at 600°C, and ground to 180 mesh to obtain porous active calcium silicate powder.

[0076] (2) The dried nano zinc oxide powder, anhydrous ethanol, and rare earth coupling agent WG-1 were added to a beaker at a mass ratio of 100:90:6. The mixture was stirred under ultrasonic conditions at 80 Hz for 3 hours. Then, a 5% cerium nitrate solution was slowly added, wherein the molar mass ratio of zinc to cerium was 100:1. After stirring evenly, the mixture was filtered, dried at 60 ℃, and ground to 180 mesh to obtain modified nano zinc oxide powder.

[0077] (3) The anatase mesoporous TiO2, porous active calcium silicate and modified nano zinc oxide were thoroughly mixed to obtain a composite carrier;

[0078] (4) The active component precursor salt was dissolved in deionized water to make a mixed solution and added to the composite carrier. After mixing for 4 hours, sodium dodecylbenzenesulfonate was added as a surface dispersant. The mass ratio of the surface dispersant to the composite carrier was 2%. After mixing for 1 hour, the co-catalyst precursor salt was added as a mixed solution and mixed for 2 hours. Carboxymethyl cellulose was added as a molding aid. The mass ratio of the molding aid to the composite carrier was 3%. After mixing evenly, the mixture was aged at 35°C for 72 hours, extruded, dried at 75°C for 65 hours, and finally calcined at 630°C for 22 hours to obtain the anti-arsenic poisoning denitrification catalyst.

[0079] Comparative Example 1

[0080] A denitrification catalyst, compared with Example 1, is identical to Example 1 except that the composite support in this comparative example does not contain porous active calcium silicate and modified nano zinc oxide.

[0081] Comparative Example 2

[0082] A denitration catalyst, compared with Example 1, is identical to Example 1 only in that the composite support in this comparative example is composed of anatase TiO2 and porous active calcium silicate (mass ratio of the two is 100:3), and the rest of the formulation and preparation method are the same.

[0083] Comparative Example 3

[0084] A denitration catalyst, compared with Example 1, differs only in that the composite support in this comparative example is composed of anatase TiO2 and modified nano zinc oxide (the mass ratio of the two is 100:1.5), while the rest of the formulation and preparation method are the same as in Example 1.

[0085] Comparative Example 4

[0086] A denitrification catalyst, compared with Example 1, is identical to Example 1 except that no co-catalyst is added in this comparative example, while the rest of the formulation and preparation method are the same.

[0087] Test 1

[0088] The activity of the catalysts prepared in Examples 1-5 and Comparative Examples 1-4 of this invention was tested. The denitrification efficiency was tested at a flue gas temperature of 250-450℃ under the following conditions: test temperature 250-450℃, NH3 volume concentration 500ppm, NH3 / NO = 1, GHSV = 120000h. -1 The test results are shown in Table 1.

[0089] Table 1. Denitrification efficiency of different denitrification catalysts

[0090]

[0091] As shown in Table 1, the anti-arsenic poisoning catalyst provided by the present invention has high denitrification efficiency and excellent denitrification performance in the temperature range of 250-450℃.

[0092] Test 2

[0093] The catalysts prepared in Examples 1-5 and Comparative Examples 1-4 of this invention were tested for resistance to alkali poisoning, resistance to arsenic poisoning, surface area of ​​catalysts with As2O3 deposition amount and N2 selectivity after 120 h.

[0094] The catalysts were loaded with 1.5% K2O and 1.8% As2O3 by mass, respectively, and their denitrification performance was tested at 350℃. The test results are shown in Table 2.

[0095] The process of loading K2O onto the catalyst is as follows: the denitrification catalyst is ground, passed through an 80-100 mesh sieve, the catalyst powder is weighed, placed in a three-necked flask, KNO3 solution is added, the mixture is stirred in a water bath at 80°C for 2 hours, then dried, and calcined at 550°C in air atmosphere to obtain the catalyst.

[0096] The process of loading As2O3 onto the catalyst is as follows: The denitrification catalyst is placed in a fixed-bed reactor, and an arsenic-containing solution is injected into the preheater via a peristaltic pump. After heating, gaseous As2O3 is formed. A N2 / O2 mixture is used as the carrier gas to carry the gaseous As2O3 into the reactor, where it is deposited on the catalyst. By controlling parameters such as the concentration of the arsenic-containing solution, the flow rate of the peristaltic pump, and the temperature of the preheater, the loading of As2O3 onto the catalyst is accurately achieved.

[0097] Table 2 Performance of different denitrification catalysts

[0098]

[0099] As shown in Table 2, the denitrification catalyst prepared in this invention exhibits good denitrification activity (up to 90.5%) with 1.8% As2O3 loading and good denitrification activity (up to 94.3%) with 1.5% K2O loading at a flue gas temperature of 350℃. The N2 selectivity is as high as 99.9%, and the As2O3 deposition on the catalyst surface is only 0.09% after 120h, demonstrating good resistance to arsenic and alkali poisoning and reducing the deposition of As2O3 on the catalyst surface.

[0100] The arsenic poisoning-resistant denitrification catalyst provided by this invention uses V-Nd-Y-Ox composite oxide as the active component and Mo, Ce, and Ni as co-catalysts. It can effectively inhibit the poisoning of the catalyst by arsenic and also has good synergistic anti-alkali metal poisoning performance. It can be widely used in coal-fired power plants, waste-to-energy plants, steel industry, etc., and has broad application prospects.

[0101] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. An arsenic poisoning resistant catalyst, characterized in that, It includes a composite support, an active component, and a co-catalyst, wherein the mass ratio of the active component to the composite support is (3-8):100, and the mass ratio of the co-catalyst to the composite support is (2-10):

100. The composite carrier includes anatase TiO2, porous active calcium silicate, and modified nano zinc oxide; The active components include vanadium oxide, neodymium oxide, and yttrium oxide; The cocatalyst includes molybdenum oxide, cerium oxide, and nickel oxide; Its preparation method includes the following steps: (1) Calcium silicate powder, chitosan, stearic acid and carboxymethyl cellulose are added to a reaction vessel in a mass ratio of 100:(1-4):(0.5-2):(0.1-0.5). The mixture is stirred at 120-150℃ and kept at the temperature for 120-180 minutes. After rapid cooling and precipitation, the mixture is dried at 60-80℃, calcined at 400-600℃, and ground to 120-180 mesh to obtain porous active calcium silicate. (2) The dried nano zinc oxide powder, anhydrous ethanol, and rare earth coupling agent are mixed and stirred for 1-3 hours at a mass ratio of 100:(60-90):(2-6). Then, a 5% cerium nitrate solution is slowly added and stirred evenly. After filtration, drying, and grinding to 120-180 mesh, modified nano zinc oxide is obtained. (3) Thoroughly mix anatase TiO2, porous active calcium silicate and modified nano zinc oxide to obtain a composite carrier; (4) Add the mixed solution of the active component precursor salt to the composite carrier and mix for 2-5 hours. Add the surface dispersant and mix for 1-2 hours. Add the mixed solution of the catalyst precursor salt and mix for 2-5 hours. Add the molding aid and mix evenly. After aging, extrusion, drying and calcination, the arsenic poisoning denitrification catalyst is obtained.

2. The arsenic poisoning resistant catalyst according to claim 1, characterized in that, The mass ratio of anatase TiO2, porous active calcium silicate, and modified nano zinc oxide in the composite carrier is 100:(1-5):(1-3).

3. The arsenic poisoning resistant catalyst according to claim 1, characterized in that, The mass ratio of vanadium oxide, neodymium oxide, and yttrium oxide in the active component is 10:(1-8):(0.5-5).

4. The arsenic poisoning resistant catalyst according to claim 1, characterized in that, The mass ratio of molybdenum oxide, cerium oxide, and nickel oxide in the co-catalyst is 10:(2-8):(0.1-3).

5. The arsenic poisoning resistant catalyst according to claim 1, characterized in that, The surface dispersant in step (4) is at least one of polysulfonic acid, sodium dodecylbenzenesulfonate, and dodecyl acetic acid.

6. The arsenic poisoning resistant catalyst according to claim 5, characterized in that, The mass ratio of the surface dispersant to the composite carrier is (0.3-2):

100.

7. The arsenic poisoning resistant catalyst according to claim 1, characterized in that, The molding aid in step (4) is at least one of glass fiber, carboxymethyl cellulose, amino cellulose, and liquid paraffin; the mass ratio of the molding aid to the composite carrier is (0.3-3):

100.

8. The arsenic poisoning resistant catalyst according to claim 1, characterized in that, In step (4), the aging temperature is 20-35℃ and the aging time is 24-72h; the drying temperature is 40-75℃ and the drying time is 30-65h; the calcination temperature is 500-630℃ and the calcination time is 12-40h.

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