Catalyst for acrylonitrile absorber tail gas treatment, its preparation method and application

Abstract

The application provides a catalyst for acrylonitrile absorption tower tail gas treatment and a preparation method and application thereof, and the catalyst comprises 80-97 parts by mass of a metal skeleton carrier, 0.5-1 part by mass of an active component, 5-10 parts by mass of an additive and 0.2-0.5 part by mass of a hydrothermal stability material; wherein the active component is at least one of platinum oxide and palladium oxide; the additive is at least one of titanium oxide, vanadium oxide, chromium oxide, manganese oxide, cobalt oxide, nickel oxide, copper oxide and rare earth metal oxide; and the hydrothermal stability material is magnesium-aluminum spinel. The catalyst has excellent activity and stability.

Description

TECHNICAL FIELD

[0001] The present application belongs to the field of gas purification, and particularly relates to a catalyst for treating tail gas of an acrylonitrile absorption tower and a preparation method and application thereof. BACKGROUND

[0002] An acrylonitrile production process adopts propylene ammoxidation technology, and takes propylene and ammonia as main raw materials, to generate acrylonitrile and other byproducts under the action of a catalyst, and then to obtain acrylonitrile products through processes such as quenching, recovery and refining. When an acrylonitrile device is normally produced, the waste gas discharged from the top of an absorption tower is called tail gas of the absorption tower, and mainly contains nitrogen, carbon dioxide, water vapor, and a certain amount of propane, propylene, acrylonitrile and the like. Direct discharge into the atmosphere will cause pollution to the environment, and pollutants in the tail gas of the absorption tower need to be purified to meet the national emission requirements of non-methane total hydrocarbon ≤120 mg / m 3 , and acrylonitrile content ≤0.5 mg / m 3 .

[0003] Current tail gas treatment methods mainly include thermal combustion and catalytic oxidation. The thermal combustion method is to heat the harmful gas to 600-800℃, to convert various organic matters in the tail gas into inorganic matters such as carbon dioxide and water, and to discharge them into the atmosphere together. The nitrogen oxide concentration in the flue gas can be controlled by controlling the combustion temperature and the air excess amount, so as to meet the emission standard. This treatment method has large flue gas emission, contains pollutants such as nitrogen oxides, has large fuel consumption, is not conducive to energy saving, and has relatively high overall treatment cost. The catalytic oxidation method is to make the combustible matter in the harmful gas completely oxidize and decompose at 350-600℃ under the action of a catalyst, generally without adding auxiliary fuel, and can be used for low-concentration and complex-component combustible matter purification. This method has high purification efficiency, low reaction temperature, and does not produce secondary pollution.

[0004] The catalysts for catalytic oxidation mainly include noble metal catalysts and non-noble metal oxide catalysts. The noble metal catalysts have excellent catalytic oxidation activity, but have low thermal stability, are easy to sinter and flow at high temperature; the non-noble metal oxide catalysts, such as copper, cobalt, manganese and chromium oxides and composite oxides, have high thermal stability, but have lower catalytic oxidation activity than the noble metal catalysts.

[0005] CN101362051A discloses a new process for treating acrylonitrile tail gas, which has the dual functions of catalytic oxidation and catalytic reduction. However, the process adopts traditional noble metal oxidation catalysts and vanadium / titanium / tungsten reduction catalysts, and such catalyst materials have the disadvantages of high cost and relatively low SCR catalytic removal performance.

[0006] CN 102513145A discloses a Fe molecular sieve SCR catalyst for purification of NOx in acrylonitrile oxidation tail gas and a preparation method, wherein a commercial ZSM-5 molecular sieve, Y molecular sieve, ferrierite or beta molecular sieve is used as a carrier, and Fe with a mass fraction of 0.3-10.0% is introduced by impregnation or ion exchange 3+ As an active component, the catalyst can achieve efficient catalytic removal of NOx in tail gas after acrylonitrile oxidation under oxygen-rich conditions.

[0007] CN102734812A discloses a method for removing acrylonitrile-containing waste gas, which adopts a transition metal supported mesoporous molecular sieve catalyst to remove acrylonitrile-containing waste gas by catalytic reaction. The mesoporous molecular sieve carrier is MCM-41, MCM-48, SBA-15, SBA-16, KIT-5 or KIT-6, and the transition metal active component is one or more of Cu, Co, Cr, Mn, Ag or V, and the mass ratio of the carrier to the transition metal component is 1:0.02-0.07. The molecular sieve catalyst is placed in a fixed bed quartz reactor, the reaction furnace temperature is raised to 350-650℃ under normal pressure, and the mixed gas of acrylonitrile-containing waste gas, oxygen and nitrogen is introduced into the reaction furnace at an air speed of 17000-24000h -1 The waste gas is removed by catalytic combustion. The waste gas removal efficiency of the method is low.

[0008] CN101362051A discloses a process for treating tail gas of an acrylonitrile device, which is suitable for acrylonitrile waste gas discharged from an acrylonitrile device. After free water in the acrylonitrile tail gas is separated by a gas-liquid separator, the acrylonitrile tail gas is mixed with air, and catalytic oxidation reaction is carried out with a noble metal honeycomb catalyst as a catalyst to convert harmful volatile organic compounds into carbon dioxide and water. Then, selective catalytic reduction reaction is carried out with the selective honeycomb catalyst as a catalyst and additional ammonia to reduce nitrogen oxides in the tail gas into nitrogen and water. The method is complex in operation, and additional ammonia is required, which results in high material consumption.

[0009] Therefore, further research is needed on the catalyst for treating tail gas of an acrylonitrile absorption tower. SUMMARY

[0010] The main purpose of the present application is to provide a catalyst for treating tail gas of an acrylonitrile absorption tower and a preparation method and application thereof, so as to overcome the defects of poor hydrothermal stability, low activity, and poor removal effect of non-methane total hydrocarbons and acrylonitrile in tail gas in the prior art.

[0011] In order to achieve the above purpose, the present application provides a catalyst for treating tail gas of an acrylonitrile absorption tower, which comprises 80-97 parts by mass of a metal framework carrier, 0.5-1 part by mass of an active component, 5-10 parts by mass of an additive, and 0.2-0.5 part by mass of a hydrothermal stabilizing material.

[0012] The active component is at least one of platinum oxide and palladium oxide; the auxiliary agent is at least one of titanium oxide, vanadium oxide, chromium oxide, manganese oxide, cobalt oxide, nickel oxide, copper oxide and rare earth metal oxide; and the hydrothermal stable material is magnesium aluminum spinel.

[0013] The catalyst for treating tail gas of an acrylonitrile absorption tower according to the application, wherein the metal framework carrier is an Al2O3 / Fe2O3 composite carrier.

[0014] The catalyst for treating tail gas of an acrylonitrile absorption tower according to the application, wherein the active component is at least one of PtO2 and PdO2.

[0015] The catalyst for treating tail gas of an acrylonitrile absorption tower according to the application, wherein the auxiliary agent is at least one of TiO2, V2O3, CrO2, MnO2, CoO, NiO, CuO, La2O3, CeO2 and IrO2.

[0016] To achieve the above-mentioned purpose, the application further provides a preparation method of the catalyst for treating tail gas of an acrylonitrile absorption tower, which comprises the following steps: mixing the active component, the auxiliary agent, the hydrothermal stable material and water into a suspension, grinding the suspension, coating the slurry on the metal framework carrier, drying, and roasting to obtain the catalyst for treating tail gas of an acrylonitrile absorption tower.

[0017] The preparation method of the catalyst for treating tail gas of an acrylonitrile absorption tower according to the application, wherein the step of mixing the active component, the auxiliary agent, the hydrothermal stable material and water into a suspension comprises the following steps: mixing the auxiliary agent and water into a suspension, and then adding the active component and the hydrothermal stable material.

[0018] The preparation method of the catalyst for treating tail gas of an acrylonitrile absorption tower according to the application, wherein the method of coating the slurry on the metal framework carrier comprises the following steps: placing the carrier in a vacuum environment, and coating the slurry on the metal framework carrier by deposition complex impregnation under the condition of 150-180 DEG C of the prepared slurry.

[0019] To achieve the above-mentioned purpose, the application further provides an application of the catalyst in removing non-methane total hydrocarbon and acrylonitrile from tail gas of an acrylonitrile absorption tower.

[0020] The application according to the application, wherein the reaction conditions for removing non-methane total hydrocarbon and acrylonitrile from tail gas of an acrylonitrile absorption tower are as follows: the reaction temperature is 240-650 DEG C, the reaction pressure is 0.01-0.015 MPa, the reaction space velocity is 10000-15000 h-1, and the volume ratio of the tail gas of the acrylonitrile absorption tower to air is 2.5-3.5. -1

[0021] ​The beneficial effects of the present application are as follows:

[0022] The present application greatly improves the hydrothermal stability of the catalyst by adding magnesium aluminate spinel; meanwhile, the catalyst has excellent activity and good removal capacity for non-methane total hydrocarbons and residual acrylonitrile in the tail gas of the acrylonitrile absorption tower; in addition, the catalyst has the characteristics of high activity and strong stability, and the treated tail gas meets the national emission standards.

[0023] The catalyst coating prepared by the method of the present application has firm bonding, uniform coating and low coating shedding rate. BRIEF DESCRIPTION OF DRAWINGS

[0024] Figure 1 The evaluation effect of the catalyst of the present application after catalysis for 1000h. DETAILED DESCRIPTION

[0025] The technical solutions of the present application are described in detail below, and the following embodiments are implemented on the premise of the technical solutions of the present application, and a detailed implementation process is given, but the protection scope of the present application is not limited to the following embodiments, and the structures or experimental methods not marked with specific conditions in the following embodiments are usually according to conventional conditions.

[0026] The present application provides a catalyst for treating the tail gas of an acrylonitrile absorption tower, which comprises 80-97 parts by mass of a metal skeleton carrier, 0.5-1 part by mass of an active component, 5-10 parts by mass of an auxiliary agent, and 0.2-0.5 part by mass of a hydrothermal stability material.

[0027] The active component is at least one of platinum oxide and palladium oxide; the auxiliary agent is at least one of titanium oxide, vanadium oxide, chromium oxide, manganese oxide, cobalt oxide, nickel oxide, copper oxide, and rare earth metal oxide; and the hydrothermal stability material is magnesium aluminate spinel.

[0028] The catalyst of the present application has good hydrothermal stability due to the addition of the hydrothermal stability material magnesium aluminate spinel. In addition, the catalyst of the present application has excellent activity and good removal capacity for non-methane total hydrocarbons and residual acrylonitrile in the tail gas of the acrylonitrile absorption tower, and has the characteristics of high activity and strong stability, and the treated tail gas meets the national emission standards.

[0029] In one embodiment, the metal framework carrier of the present application is an Al2O3 / Fe2O3 composite carrier. In another embodiment, the metal framework carrier is in the form of a shaped solid plate, which is composed of Al2O3 and Fe2O3. The catalyst of the present application comprises 80-97 parts by mass of the metal framework carrier, in one embodiment, for example, 85-97 parts by mass, 88-95 parts by mass.

[0030] The active component of the catalyst of the present application is at least one of platinum oxide, palladium oxide; in one embodiment, the active component of the catalyst of the present application is at least one of PtO2, PdO2. The catalyst of the present application comprises 0.5-1 parts by mass of the active component, in one embodiment, for example, 0.6 parts by mass, 0.7 parts by mass, 0.8 parts by mass, 0.9 parts by mass.

[0031] The auxiliary component of the catalyst of the present application is at least one of titanium oxide, vanadium oxide, chromium oxide, manganese oxide, cobalt oxide, nickel oxide, copper oxide, rare earth metal oxide. In one embodiment, the auxiliary component of the catalyst of the present application is at least one of TiO2, V2O3, CrO2, MnO2, CoO, NiO, CuO, La2O3, CeO2, IrO2.

[0032] The catalyst of the present application comprises 5-10 parts by mass of the auxiliary component, in one embodiment, the catalyst of the present application comprises 6 parts by mass, 7 parts by mass, 8 parts by mass, 9 parts by mass of the auxiliary component.

[0033] In one embodiment, the catalyst of the present application is composed of 88.8 parts by mass of the metal framework carrier, 1.0 part by mass of CoO, 1.0 part by mass of NiO, 1.0 part by mass of TiO2, 1.0 part by mass of CrO2, 1.0 part by mass of MnO2, 1.0 part by mass of CuO, 1.0 part by mass of V2O3, 1.0 part by mass of La2O3, 1.0 part by mass of CeO2, 1.0 part by mass of IrO2, 0.2 part by mass of PtO2, 0.6 part by mass of PdO2, 0.4 part by mass of magnesium aluminate spinel.

[0034] The hydrothermal stability material of the present application is an inorganic composite material, preferably magnesium aluminate spinel. The catalyst of the present application comprises 0.2-0.5 parts by mass of the hydrothermal stability material, for example, 0.2 parts by mass, 0.3 parts by mass, 0.4 parts by mass, 0.5 parts by mass.

[0035] In one embodiment, the magnesium aluminate spinel of the present application is prepared by co-precipitation of magnesium salt and aluminum salt through a micro-reactor.

[0036] The application further provides a preparation method of the catalyst for treating tail gas of an acrylonitrile absorption tower, which comprises the following steps: mixing an active component, an auxiliary agent, a hydrothermal stabilizing material and water into a suspension, grinding the suspension, coating the slurry on a metal framework carrier, drying, and roasting to obtain the catalyst for treating tail gas of an acrylonitrile absorption tower.

[0037] In an embodiment, the auxiliary agent and the water are mixed into a suspension first, and then the active component and the hydrothermal stabilizing material are added.

[0038] In an embodiment, the suspension is ground by using a ball mill, and the particle size after grinding is 20-100 μm.

[0039] In an embodiment, after the slurry is coated on the metal framework carrier, the temperature for drying is 100-120 ℃, and the roasting temperature is not particularly limited, and a conventional roasting temperature in the art can be used.

[0040] The catalyst coating prepared by using the method of the application has firm combination, uniform coating and low coating shedding rate.

[0041] The catalyst of the application can be used for removing non-methane total hydrocarbons and acrylonitrile in tail gas of an acrylonitrile absorption tower of an industrial device, and the tail gas is detected by using gas chromatography after passing through a fixed bed reactor, and the catalyst activity is determined by the content of the tail gas. -1 The reaction temperature for treating the tail gas of the acrylonitrile absorption tower by using the catalyst of the application is 240-650 ℃, the reaction pressure is 0.01-0.015 MPa, the reaction space velocity is 10000-15000 h-1, the volume ratio of the tail gas of the acrylonitrile absorption tower to air is 2.5-3.5, the content of non-methane total hydrocarbons in the tail gas of the acrylonitrile absorption tower of the industrial device is 16673 mg / m3, and the content of acrylonitrile is 40 mg / m3.

[0042] In an embodiment, the content of non-methane total hydrocarbons in the tail gas of the acrylonitrile absorption tower of the industrial device is 16673 mg / m3, and the content of acrylonitrile is 40 mg / m3. 3 3 .

[0043] The technical scheme of the application will be further described in detail through specific examples. Unless otherwise specified, the following "parts" all refer to mass parts.

[0044] Raw material or equipment source: acrylonitrile tail gas, Daqing Petrochemical Company; gas chromatograph, Tianmei.

[0045] Evaluation and analysis method: self-built

[0046] Example 1

[0047] ​A homogeneous suspension of 1.0 part TiO2, 1.0 part CrO2, 1.0 part CuO, 1.0 part V2O3, 1.0 part La2O3 and 100 parts deionized water is prepared, 0.5 part PtO2, 0.5 part PdO2 and 0.2 part magnesium aluminate spinel are added, the liquid is ground into a 20-100 μm slurry by a high-energy ball mill, then the carrier is coated by using quantitative vacuum coating technology, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-1.

[0048] Wherein, the prepared catalyst is 100 parts by mass, subtracting the parts of the above active components, additives, hydrothermal stabilizing materials, the rest is the mass fraction of the carrier, the following examples are the same.

[0049] Example 2

[0050] A homogeneous suspension of 2.5 parts TiO2, 2.5 parts CrO2 and 75 parts deionized water is prepared, 0.3 part PtO2, 0.3 part PdO2 and 0.3 part magnesium aluminate spinel are added, the liquid is ground into a 20-100 μm slurry by a high-energy ball mill, then the carrier is coated by using quantitative vacuum coating technology, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-2.

[0051] Example 3

[0052] A homogeneous suspension of 3.0 parts TiO2, 1.0 part La2O3, 1.0 part CeO2 and 100 parts deionized water is prepared, 0.2 part PtO2, 0.3 part PdO2 and 0.4 part magnesium aluminate spinel are added, the liquid is ground into a 20-100 μm slurry by a high-energy ball mill, then the carrier is coated by using quantitative vacuum coating technology, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-3.

[0053] Example 4

[0054] A homogeneous suspension of 3.0 parts CrO2, 2.0 parts CuO and 100 parts deionized water is prepared, 0.4 part PtO2, 0.3 part PdO2 and 0.3 part magnesium aluminate spinel are added, the liquid is ground into a 20-100 μm slurry by a high-energy ball mill, then the carrier is coated by using quantitative vacuum coating technology, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-4.

[0055] Example 5

[0056] A homogeneous suspension of 1.5 parts TiO2, 1.5 parts CrO2, 2.0 parts MnO2, 1.0 part CuO, 1.0 part CeO2 and 210 parts deionized water is prepared, 0.5 part PtO2, 0.5 part PdO2 and 0.4 part magnesium aluminate spinel are added, the liquid is ground into a 20-100 μm slurry by a high-energy ball mill, and then the carrier is coated by using a quantitative vacuum coating technique, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-5.

[0057] Example 6

[0058] A homogeneous suspension of 2.0 parts TiO2, 2.0 parts MnO2, 2.0 parts V2O3, 2.0 parts CeO2 and 160 parts deionized water is prepared, 0.2 part PtO2, 0.6 part PdO2 and 0.3 part magnesium aluminate spinel are added, the liquid is ground into a 20-100 μm slurry by a high-energy ball mill, and then the carrier is coated by using a quantitative vacuum coating technique, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-6.

[0059] Example 7

[0060] A homogeneous suspension of 3.0 parts CoO, 1.0 part TiO2, 3.0 parts La2O3, 1.0 part CeO2 and 100 parts deionized water is prepared, 0.4 part PtO2, 0.4 part PdO2 and 0.4 part magnesium aluminate spinel are added, the liquid is ground into a 20-100 μm slurry by a high-energy ball mill, and then the carrier is coated by using a quantitative vacuum coating technique, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-7.

[0061] Example 8

[0062] A homogeneous suspension of 1.0 part CoO, 1.0 part NiO, 1.0 part TiO2, 1.0 part CrO2, 1.0 part MnO2, 1.0 part CuO, 1.0 part V2O3, 1.0 part La2O3, 1.0 part CeO2, 1.0 part IrO2 and 250 parts deionized water is prepared, 0.2 part PtO2, 0.6 part PdO2 and 0.4 part magnesium aluminate spinel are added, the liquid is ground into a 20-100 μm slurry by a high-energy ball mill, and then the carrier is coated by using a quantitative vacuum coating technique, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-8.

[0063] Example 9

[0064] A homogeneous suspension of 2.0 parts of CoO, 2.0 parts of CrO2, 2.0 parts of MnO2, 2.0 parts of CuO, 2.0 parts of La2O3 and 200 parts of deionized water is prepared, 0.4 parts of PtO2, 0.6 parts of PdO2 and 0.5 parts of magnesium aluminate spinel are added, the liquid is ground into a slurry of 20-100 μm by a high-energy ball mill, then the carrier is coated by using the quantitative vacuum coating technology, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-9.

[0065] Example 10

[0066] A homogeneous suspension of 3.0 parts of CoO, 3.0 parts of NiO2, 1.0 part of CeO2, 3.0 parts of IrO2 and 200 parts of deionized water is prepared, 0.5 parts of PtO2, 0.5 parts of PdO2 and 0.5 parts of magnesium aluminate spinel are added, the liquid is ground into a slurry of 20-100 μm by a high-energy ball mill, then the carrier is coated by using the quantitative vacuum coating technology, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-10.

[0067] Example 11

[0068] A homogeneous suspension of 5.0 parts of CrO2, 5.0 parts of IrO2 and 200 parts of deionized water is prepared, 0.3 parts of PtO2, 0.6 parts of PdO2 and 0.4 parts of magnesium aluminate spinel are added, the liquid is ground into a slurry of 20-100 μm by a high-energy ball mill, then the carrier is coated by using the quantitative vacuum coating technology, through deposition complex immersion, dried and calcined to prepare a monolithic catalyst CAT-11.

[0069] Catalyst effect evaluation:

[0070] Examples 12-22

[0071] To evaluate the catalytic effect of the catalyst, the acrylonitrile absorption tower tail gas is used as the raw material in the industrial device, the tail gas passes through the fixed bed reactor under the evaluation conditions in Table 1 below, and the catalyst activity is determined by gas chromatography detection. The specific evaluation results are shown in Table 1 below.

[0072] Table 1 Catalyst evaluation effect under evaluation condition 1

[0073]

[0074] As shown in Table 1, the catalyst prepared by the present application has a non-methane total hydrocarbon content of 16673 ppm, an acrylonitrile content of 40 ppm, a reaction temperature of 400°C, a reaction pressure of 0.01 MPa, a reaction space velocity of 10000 h -1The non-methane total hydrocarbon is less than 120 ppm and the acrylonitrile is less than 5 ppm after treatment, which shows that the catalyst of the present application has good catalytic effect.

[0075] Examples 23-33

[0076] To evaluate the catalytic effect of the catalyst, the tail gas of the acrylonitrile absorption tower is used as raw material in an industrial device, and the tail gas is detected by gas chromatography after passing through a fixed bed reactor under the evaluation conditions in Table 2 below. The catalyst activity is determined by the content of the tail gas. The specific evaluation results are shown in Table 2 below.

[0077] Table 2 Evaluation results of catalyst under evaluation condition 2

[0078]

[0079] As shown in Table 2, the catalyst prepared in the present application has good catalytic effect under the conditions of non-methane total hydrocarbon content of 16673 ppm, acrylonitrile content of 40 ppm, reaction temperature of 550℃, reaction pressure of 0.01 MPa, reaction space velocity of 12000 h -1

[0080] Examples 34-44

[0081] To evaluate the catalytic effect of the catalyst, the tail gas of the acrylonitrile absorption tower is used as raw material in an industrial device, and the tail gas is detected by gas chromatography after passing through a fixed bed reactor under the evaluation conditions in Table 3 below. The catalyst activity is determined by the content of the tail gas. The specific evaluation results are shown in Table 3 below.

[0082] Table 3 Evaluation results of catalyst under evaluation condition 3

[0083]

[0084] As shown in Table 3, the catalyst prepared in the present application has good catalytic effect under the conditions of non-methane total hydrocarbon content of 16673 ppm, acrylonitrile content of 40 ppm, reaction temperature of 610℃, reaction pressure of 0.012 MPa, reaction space velocity of 14000 h -1

[0085] Example 45

[0086] ​​To evaluate the long-term catalytic effect of the catalyst, in an industrial plant, using the tail gas from the acrylonitrile absorber as feedstock, the reaction was carried out at a non-methane total hydrocarbon content of 16673 ppm, an acrylonitrile content of 40 ppm, a reaction temperature of 550℃, a reaction pressure of 0.01 MPa, and a reaction space velocity of 12000 h⁻¹. -1 Under the evaluation condition of a gas-to-air volume ratio of 3.0, the exhaust gas was analyzed by gas chromatography after passing through a fixed-bed reactor to investigate the catalytic activity and stability of the catalyst after 1000 h of catalysis. The evaluation results are as follows: Figure 1 .

[0087] Depend on Figure 1 As shown, the catalyst of this invention treats the tail gas of an acrylonitrile absorption tower in an industrial plant for 1000 hours. The content of non-methane total hydrocarbons and acrylonitrile in the treated tail gas can meet the national emission standards. Therefore, the catalyst of this invention has good catalytic activity, good stability and long service life.

[0088] Of course, the present invention may have other various embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention, but these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A catalyst for treating the tail gas of an acrylonitrile absorber, characterized in that, It includes 80-97 parts by weight of a metal skeleton carrier, 0.5-1 parts by weight of an active component, 5-10 parts by weight of an additive, and 0.2-0.5 parts by weight of a hydrothermal stabilizer. The active component is at least one of PtO2 and PdO2; the auxiliary agent is at least one of TiO2, V2O3, CrO2, MnO2, CoO, NiO, CuO, La2O3, CeO2, and IrO2; the hydrothermal stabilizing material is magnesium aluminum spinel; and the metal framework carrier is an Al2O3 / Fe2O3 composite carrier.

2. The catalyst for treating acrylonitrile absorber tail gas according to claim 1, characterized in that, The metal skeleton carrier has a mass fraction of 85-97 parts.

3. The method for preparing the catalyst for acrylonitrile absorber tail gas treatment according to claim 1 or 2, characterized in that, The active component, additives, hydrothermal stabilizer and water are mixed into a suspension, the suspension is ground, and then the slurry is coated onto a metal skeleton carrier, dried and calcined to obtain a catalyst for the treatment of acrylonitrile absorber tail gas.

4. The method for preparing the catalyst for acrylonitrile absorber tail gas treatment according to claim 3, characterized in that, The steps for mixing the active ingredient, additives, hydrothermal stabilizer and water into a suspension are as follows: mix the additives and water into a suspension, and then add the active ingredient and hydrothermal stabilizer.

5. The method for preparing the catalyst for acrylonitrile absorber tail gas treatment according to claim 3, characterized in that, The method for coating the slurry onto the metal skeleton carrier is as follows: the metal skeleton carrier is placed in a vacuum environment, and the slurry is coated onto the metal skeleton carrier by deposition complexing impregnation at 150-180°C.

6. The application of the catalyst according to claim 1 or 2 in the removal of non-methane hydrocarbons and acrylonitrile from the tail gas of an acrylonitrile absorber.

7. The application according to claim 6, characterized in that, The reaction conditions for removing non-methane hydrocarbons and acrylonitrile from the tail gas of the acrylonitrile absorber are as follows: reaction temperature 240-650℃, reaction pressure 0.01-0.015MPa, and reaction space velocity 10000-15000h⁻¹. -1 The volume ratio of the acrylonitrile absorber tail gas to air is 2.5-3.5.

Images