A catalyst for treating industrial waste gas, its preparation method and application

Abstract

The present invention provides a catalyst for treating industrial waste gas, a preparation method thereof and an application thereof. The catalyst comprises a honeycomb carrier and a coating present on the inner surface and / or outer surface of the honeycomb carrier. The coating comprises a supported silicon oxide, a second auxiliary agent and a third auxiliary agent. Wherein, the second auxiliary agent is selected from at least one of the oxides of Group IVB elements, and the third auxiliary agent is selected from at least one of the oxides of Group VIIIB noble metal elements. The supported silicon oxide comprises a carrier, and an active component and a first auxiliary component supported on the carrier. Wherein, the carrier comprises silicon dioxide, and the active component comprises W4O 11 , and the first auxiliary component comprises a rare earth metal oxide. By using noble metals and supported silicon oxides as the main active components, the present invention has good catalytic activity and high adhesion to the carrier.

Description

Technical Field

[0001] The present invention relates to the technical field of catalysts for industrial waste gas, and particularly relates to a catalyst for treating industrial waste gas, a preparation method thereof, and an application thereof. Background Art

[0002] In the process of petrochemical production, waste gas containing volatile organic compounds is often generated. If these waste gases are directly discharged into the atmosphere, they will cause great harm to the atmospheric environment. Most volatile organic compounds have peculiar smells and can cause diseases or even cancer to the human body; especially volatile organic waste gases containing halogens, in addition to being highly toxic themselves, can also undergo photochemical reactions with ozone to produce photochemical smog, causing great damage to the earth's environment. Therefore, effectively treating the organic waste gas generated in the petrochemical industrial production process is an important topic in environmental science. The catalytic combustion method reduces the operating temperature to 280 - 450°C with the help of a catalyst, greatly reducing energy consumption, being safe, stable in operation, having low operating costs, and not generating nitrogen oxides, thus not producing secondary pollution. Therefore, the catalytic combustion method for treating organic waste gas is a relatively ideal method.

[0003] Catalysts for treating organic waste gas are often prepared by the coating method, that is, a coating slurry containing the required active components is coated onto a carrier. For example:

[0004] CN201911298212.1 discloses an adsorption / catalytic material for waste gas treatment. The adsorption / catalytic material includes a honeycomb carrier and an active coating composed of molecular sieve, surfactant, transition metal solution, and binder; by using SiO2 - Al2O3 - ZrO2 composite sol as the binder, the firmness between the components of the active coating and the honeycomb carrier is effectively enhanced, and by making the mass ratio of the honeycomb carrier to the active coating be 8:1 - 5:1, the loading of the molecular sieve active coating on the honeycomb carrier is significantly increased.

[0005] CN201910790560.4 discloses a catalyst for catalytic combustion of VOC s and a preparation method thereof. A cordierite honeycomb ceramic or a porous metal material is used as the carrier, and a nano - coating material is coated on the carrier. A noble metal compounded with a transition metal is used as the active component, a compounded rare earth oxide is used as the catalyst assistant, and a solid solution made of an alkaline earth metal compound and a main group metal oxide is used as the carrier modifier.

[0006] CN201811568947.7 discloses a catalytic combustion VOC sOxidation catalyst and its preparation method. The oxidation catalyst of the present invention includes a carrier, a coating is coated on the carrier, the coating amount of the coating is 60-180 g / L, precious metals Pt and Pd are loaded in the coating, the loading amount of the precious metals is 0.2-5.0 g / L, wherein the mass ratio of precious metals Pt and Pd is 0.1:1-10:1, and the coating includes activated alumina, cobalt-cerium composite oxide and manganese oxide.

[0007] CN201811651009.3 discloses a diesel vehicle exhaust purification catalyst based on iron-modified hydrotalcite-derived oxide and its preparation method, which uses Pt and Pd as the main catalysts, CeO2-ZrO2 as the promoter, iron-modified hydrotalcite-derived oxide and γ-Al2O3 as the coating base materials, and cordierite honeycomb ceramics as the carrier. The preparation process includes: determination of raw material dosage, preparation of iron-modified hydrotalcite-derived oxide and preparation and coating of the coating slurry. Through the cyclic change of the lean / rich combustion conditions of the diesel engine, the catalyst can efficiently catalyze NO in the exhaust x Adsorption-reduction purification reaction. Summary of the Invention

[0008] In view of the problems existing in the above-mentioned prior art, one of the purposes of the present invention is to provide a supported silicon oxide, which has high catalytic activity through the combined use of specific active components and promoter components.

[0009] Another purpose of the present invention is to provide a preparation method of the supported silicon oxide corresponding to the first purpose.

[0010] Another purpose of the present invention is to provide a slurry for forming a coating corresponding to the above purpose.

[0011] Another purpose of the present invention is to provide an application of the slurry corresponding to the above purpose.

[0012] Another purpose of the present invention is to provide a catalyst for treating industrial waste gas corresponding to the above purpose.

[0013] Another purpose of the present invention is to provide a preparation method of the catalyst corresponding to the above purpose.

[0014] Another purpose of the present invention is to provide an application of the catalyst corresponding to the above purpose.

[0015] To achieve the first purpose, the technical solution adopted by the present invention is as follows:

[0016] A supported silicon oxide, comprising: a carrier and an active component and a first promoter component supported on the carrier, wherein the carrier includes silicon dioxide, and the active component includes W4O 11, the first promoter component includes rare earth metal oxides.

[0017] According to the present invention, it can be determined by XRD that tungsten elements exist in the form of W4O 11 . For example, the XRD diffraction pattern of the supported silicon oxide has one or more characteristic peaks of 2θ selected from 22.70±0.15, 23.55±0.15, 24.45±0.15, 32.75±0.20, 34.15±0.20, 40.70±0.20, 49.18±0.20, 53.95±0.20, and 59.52±0.15.

[0018] In some preferred embodiments of the present invention, the first promoter component includes at least one of lanthanum oxide and cerium oxide.

[0019] According to the present invention, it can be determined by XRD that the carrier is amorphous silica.

[0020] In some preferred embodiments of the present invention, the specific surface area of the carrier is 300-450 m 2 / g, preferably 350-400 m 2 / g, and the most probable pore diameter is 5-50 nm, preferably 15-30 nm.

[0021] In some preferred embodiments of the present invention, based on the total weight of the carrier, the content of the active component is 8 wt% - 24 wt%.

[0022] In some preferred embodiments of the present invention, based on the total weight of the carrier, the content of the first promoter component is 3 wt% - 12 wt%.

[0023] To achieve the second above object, the technical solution adopted by the present invention is as follows:

[0024] A method for preparing the supported silicon oxide according to any one of the above embodiments, comprising:

[0025] S1. Mixing an active component source, a first promoter component source, an organic acid, a silicon source, and a first solvent to obtain a mixed raw material system;

[0026] S2. Performing solid-liquid treatment on the mixed raw material system to obtain a solid mixture;

[0027] S3. Sequentially performing drying treatment and calcination treatment on the solid mixture to obtain the supported silicon oxide.

[0028] In some preferred embodiments of the present invention, in step S1, the active component source is selected from tungsten-containing compounds, preferably at least one of ammonium metatungstate, ammonium tungstate, sodium tungstate, and tungstic acid.

[0029] In some preferred embodiments of the present invention, in step S1, the first promoter component source is selected from rare earth metal element-containing compounds, preferably at least one of lanthanum nitrate, cerium nitrate, praseodymium nitrate, and samarium nitrate.

[0030] In some preferred embodiments of the present invention, in step S1, the organic acid is selected from at least one of citric acid, malic acid, and oxalic acid.

[0031] In some preferred embodiments of the present invention, in step S1, the silicon source is silica.

[0032] In some preferred embodiments of the present invention, in step S1, the mixing is carried out under the condition of 40°C to 80°C, preferably under the condition of 50°C to 70°C.

[0033] In some preferred embodiments of the present invention, in step S2, the solid-liquid treatment method is to evaporate the solvent, preferably carried out in a rotary evaporator, more preferably the evaporation operation is carried out under the condition of 40°C to 80°C, and further preferably the evaporation operation is carried out under the condition of 50°C to 70°C.

[0034] In some preferred embodiments of the present invention, in step S3, the conditions for the drying treatment include: the temperature is 90°C to 120°C, and the time is 6h to 24h.

[0035] In some preferred embodiments of the present invention, in step S3, the conditions for the drying treatment include: the temperature is 95°C to 110°C, and the time is 8h to 18h.

[0036] In some preferred embodiments of the present invention, in step S3, the conditions for the calcination treatment include: first calcining in an air atmosphere at a temperature range of 400°C to 600°C for 1h to 12h, and then calcining in a hydrogen atmosphere at a temperature range of 200°C to 300°C for 1h to 3h.

[0037] To achieve the third above-mentioned object, the technical solution adopted by the present invention is as follows:

[0038] A slurry for forming a coating, comprising: the supported silicon oxide according to any one of the above embodiments or the supported silicon oxide prepared by the preparation method according to any one of the above embodiments, a second promoter source, a third promoter source, an adhesive, an optional dispersant, an optional pH regulator, and a second solvent.

[0039] In some preferred embodiments of the present invention, the second promoter source is selected from at least one of the oxides of Group IVB elements, preferably at least one of titanium oxide and zirconium oxide.

[0040] In some preferred embodiments of the present invention, the third promoter source is selected from at least one of the compounds containing noble metal elements of Group VIIIB, preferably at least one of chloroplatinic acid and ruthenium chloride.

[0041] In some preferred embodiments of the present invention, the adhesive includes silica sol.

[0042] In some preferred embodiments of the present invention, the adhesive includes silica sol with a silicon content of 20 wt% to 40 wt% calculated as silicon oxide.

[0043] In some preferred embodiments of the present invention, the dispersant is selected from polyvinyl alcohol.

[0044] According to the present invention, the weight-average molecular weight of the polyvinyl alcohol is 140,000 to 200,000.

[0045] In some preferred embodiments of the present invention, the pH regulator is nitric acid.

[0046] According to the present invention, the nitric acid is commercial concentrated nitric acid.

[0047] In some preferred embodiments of the present invention, the second solvent is water.

[0048] In some preferred embodiments of the present invention, the viscosity of the slurry at 25 °C is 350 to 550 mPa·s.

[0049] In some preferred embodiments of the present invention, in the slurry, the contents of the respective components in parts by weight include:

[0050]

[0051]

[0052] In some preferred embodiments of the present invention, the slurry can be prepared by a conventional preparation process in the art. In some specific embodiments of the present invention, the preparation method of the slurry may include: contacting the supported silicon oxide, the second promoter source, the adhesive, the dispersant, the pH regulator with the second solvent, stirring for 1 to 4 h, colloidal milling for 1 to 4 h, then contacting with the third promoter source, and colloidal milling for 0.2 to 1 h to obtain the coating slurry.

[0053] According to the present invention, a slurry with a specific viscosity and / or particle size can be obtained by controlling the degree of colloidal milling.

[0054] According to the present invention, the catalyst prepared from the slurry has a relatively low shedding rate, which is beneficial to improving the stability of the catalyst.

[0055] To achieve the fourth object above, the technical solution adopted by the present invention is as follows:

[0056] An application of the slurry according to any one of the above embodiments as a raw material for forming a coating on a monolithic carrier.

[0057] In some preferred embodiments of the present invention, the monolithic carrier includes at least one of a ceramic carrier and a metal carrier. The ceramic carrier is selected from honeycomb carriers, preferably at least one of cordierite honeycomb carriers, mullite honeycomb carriers, and aluminum titanate ceramic honeycomb carriers. The metal carrier is selected from at least one of stainless steel, aluminous ferrites, and Fe-Cr-Al alloys.

[0058] According to the present invention, the mesh number of the monolithic carrier is 400-600 meshes.

[0059] To achieve the fifth object above, the technical solution adopted by the present invention is as follows:

[0060] A catalyst for treating industrial waste gas, comprising: a honeycomb carrier and a coating present on the inner surface and / or outer surface of the honeycomb carrier. The coating includes the supported silicon oxide according to any one of the above embodiments or the supported silicon oxide prepared by the preparation method according to any one of the above embodiments, a second auxiliary agent, and a third auxiliary agent. Among them, the second auxiliary agent is selected from at least one of the oxides of group IVB elements, preferably at least one of titanium oxide and zirconium oxide. The third auxiliary agent is selected from at least one of the oxides of group VIIIB noble metal elements, preferably at least one of platinum oxide and ruthenium oxide.

[0061] In some preferred embodiments of the present invention, the honeycomb carrier is selected from at least one of cordierite honeycomb carriers, mullite honeycomb carriers, and aluminum titanate ceramic honeycomb carriers.

[0062] In some preferred embodiments of the present invention, the third auxiliary agent satisfies CXPS / CICP = 2.5-6; where CXPS is the molar content of the third auxiliary agent element in the catalyst characterized by X-ray photoelectron spectroscopy, and CICP is the molar content of the third auxiliary agent element in the catalyst characterized by inductively coupled plasma.

[0063] In some preferred embodiments of the present invention, based on the total weight of the catalyst, the content of the honeycomb carrier is 40 wt% to 80 wt%, preferably 45 wt% to 70 wt%; the content of the supported silicon oxide is 20 wt% to 50 wt%, preferably 25 wt% to 40 wt%; the content of the second promoter is 1 wt% to 10 wt%, preferably 3 wt% to 6 wt%; the content of the third promoter is 0.2 wt% to 3 wt%, preferably 0.5 wt% to 2 wt%.

[0064] According to the present invention, the ultrasonic shedding rate of the catalyst is less than 3 wt%. The test conditions for the ultrasonic shedding rate include: the ultrasonic working frequency is 53 KHz, and ultrasonic treatment is carried out for 30 minutes.

[0065] To achieve the sixth above-mentioned object, the technical solution adopted by the present invention is as follows:

[0066] A preparation method of the catalyst according to any one of the above embodiments, comprising:

[0067] 1) Forming the slurry according to any one of the above embodiments on the honeycomb carrier to obtain a catalyst precursor;

[0068] 2) Sequentially performing a drying treatment and a calcination treatment on the catalyst precursor to obtain the catalyst.

[0069] According to the present invention, in step 1), the slurry can be formed on the honeycomb carrier by brushing, spraying or impregnation.

[0070] According to the present invention, in step 1), the coating amount of the slurry is 50 to 100 g / L relative to the volume of the honeycomb carrier.

[0071] In some preferred embodiments of the present invention, in step 2), the conditions of the drying treatment include: the temperature is 90 °C to 120 °C, and the time is 6 h to 24 h.

[0072] In some preferred embodiments of the present invention, the conditions of the calcination treatment include: the temperature is 400 °C to 600 °C, and the time is 1 h to 12 h.

[0073] According to the present invention, the obtained catalyst can also be subjected to a reduction treatment. The method of the reduction treatment includes pretreating the catalyst in a hydrogen-containing atmosphere at 300 °C to 500 °C. The reduction treatment can reduce the ultrasonic shedding rate of the catalyst.

[0074] According to the present invention, the hydrogen-containing atmosphere is preferably hydrogen.

[0075] To achieve the seventh above-mentioned object, the technical solution adopted by the present invention is as follows:

[0076] Use of the catalyst according to any one of the above embodiments or the catalyst prepared by the preparation method according to any one of the above embodiments in industrial waste gas treatment.

[0077] In some preferred embodiments of the present invention, the industrial waste gas includes chlorine-containing industrial waste gas. Preferably, the chlorine-containing industrial waste gas includes epichlorohydrin.

[0078] The beneficial effects of the present invention are at least in the following aspects:

[0079] First, by selecting noble metals and supported silicon oxides as the main active components, the present invention has good catalytic activity and high adhesion to the carrier.

[0080] Second, by adding an adhesive, the honeycomb carrier and the coating are tightly combined. During preparation, the grinding degree is controlled to obtain a slurry with special viscosity and particle size. The catalyst prepared by coating with this slurry has a reduced shedding rate, thereby significantly improving the stability of the prepared honeycomb catalyst. Description of the Drawings

[0081] Figure 1 XRD pattern of the supported silicon oxide prepared in Example 1. Detailed Embodiments

[0082] The present invention will be described in detail below through examples, but the protection scope of the present invention is not limited to the following description.

[0083] For those not specified in the examples, they are carried out according to conventional conditions or conditions recommended by the manufacturer. For reagents or instruments not specified in the manufacturer, they are all conventional products that can be obtained through commercial channels.

[0084] In the following embodiments, the coating stability of the catalyst is evaluated by an ultrasonic vibration test. The specific method is to put the sample into an ultrasonic cleaner with water as the medium, the ultrasonic working frequency is 53KHz, and the shedding rate is calculated after 30 minutes of ultrasonic treatment. Among them, the shedding rate = (total mass of the catalyst before ultrasonic treatment - total mass of the catalyst after ultrasonic treatment) / (total mass of the catalyst before ultrasonic treatment - mass of the honeycomb carrier before coating) * 100%.

[0085] In the following embodiments, the viscosity test method of the coating slurry is as follows: measured by a Brookfield DV2T viscometer. The test method is: at 25°C, pour 50 mL of the liquid to be measured into the measuring cup, and the measuring time is 300 s.

[0086] In the following embodiments, in the silica sol used, the silicon content is 20 wt% calculated as silicon dioxide; the grade of polyvinyl alcohol (PVA) is 124; the cylindrical honeycomb carrier is a cylindrical cordierite honeycomb carrier.

[0087] Example 1

[0088] Preparation of supported silicon oxide:

[0089] 8.06 g of ammonium metatungstate, 0.20 g of lanthanum nitrate, and 0.04 g of citric acid were dissolved in 40 g of water. 10 g of silicon dioxide was added, and the mixture was stirred at 60 °C for 1 h. Then, the water was removed by rotary evaporation at 60 °C, and then dried at 110 °C for 12 h. It was first calcined in air at 500 °C for 3 h, and then calcined in hydrogen at 200 °C for 1 h to obtain supported silicon oxide. Figure 1 The XRD diffraction pattern of the obtained supported silicon oxide is shown. The XRD diffraction pattern has characteristic peaks at 2θ of 22.70±0.20, 23.55±0.20, 24.45±0.20, 32.75±0.20, 34.15±0.20, 40.70±0.20, 49.18±0.20, 53.95±0.20, and 59.52±0.15, indicating that tungsten exists in the form of W4O 11 . After calculation, in the supported silicon oxide, the content of W4O 11 is 8 wt% based on silicon dioxide, the content of lanthanum oxide is 3 wt% based on silicon dioxide, and the balance is silicon dioxide.

[0090] Preparation of coating slurry:

[0091] 25 g of supported silicon oxide, 3 g of titanium oxide, 0.2 g of silica sol with a silica content of 20%, 0.2 g of PVA, 0.1 g of nitric acid were contacted with 100 g of water, and stirred at 3000 rpm for 1 h. The uniformly mixed slurry was milled in a colloid mill for 1 h, and then 2.5 ml of chloroplatinic acid solution with a Pt content of 200 g / L was added and milled for 0.2 h to obtain the coating slurry. The viscosity of the coating slurry was measured to be 350 mPa·s.

[0092] Preparation of industrial waste gas treatment catalyst:

[0093] The cylindrical honeycomb carrier was calcined at 200 °C for 2 h. The treated carrier was impregnated in the coating slurry for 0.5 h, then taken out, and the residual slurry in the pores was blown dry. It was dried at 110 °C for 12 h, calcined at 500 °C for 3 h, and the coating process was repeated at least 3 times until the coating amount on the honeycomb ceramic skeleton per unit volume was 50 - 100 g / L. It was calcined in air at 400 °C for 3 h, and then calcined in hydrogen at 300 °C for 1 h to obtain the waste gas treatment catalyst. The ultrasonic shedding rate was measured to be 1.8%. After calculation, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.5 wt%.

[0094] The molar content of Pt in the catalyst was determined by CXPS and CICP respectively, and it was found that CXPS / CICP = 3.5.

[0095] Example 2

[0096] Preparation of supported silicon oxide:

[0097] The difference from Example 1 was only that 24.18 g of ammonium metatungstate, 0.20 g of lanthanum nitrate, and 0.07 g of citric acid were dissolved in 40 g of water, and the supported silicon oxide was prepared under the same other conditions. After calculation, in the supported silicon oxide, the content of W4O 11 was 24 wt% based on silicon dioxide, the content of lanthanum oxide was 3 wt% based on silicon dioxide, and the balance was silicon dioxide.

[0098] Preparation of coating slurry:

[0099] Same as Example 1.

[0100] Preparation of industrial waste gas treatment catalyst:

[0101] Same as Example 1.

[0102] After calculation, in the catalyst, the content of supported silicon oxide was 25 wt%, the content of titanium oxide was 3 wt%, and the content of Pt was 0.5 wt%. After detection, the ultrasonic shedding rate was 1.9%, and CXPS / CICP = 3.6.

[0103] Example 3

[0104] Preparation of supported silicon oxide:

[0105] The difference from Example 1 was only that 8.06 g of ammonium metatungstate, 0.80 g of lanthanum nitrate, and 0.13 g of citric acid were dissolved in 40 g of water, and the supported silicon oxide was prepared under the same other conditions. After calculation, in the supported silicon oxide, the content of W4O 11 was 8 wt% based on silicon dioxide, the content of lanthanum oxide was 12 wt% based on silicon dioxide, and the balance was silicon dioxide.

[0106] Preparation of coating slurry:

[0107] Same as Example 1.

[0108] Preparation of industrial waste gas treatment catalyst:

[0109] Same as Example 1.

[0110] After calculation, in the catalyst, the supported silicon oxide is 25 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 2.1%, and CXPS / CICP = 3.4.

[0111] Example 4

[0112] Preparation of supported silicon oxide:

[0113] The difference from Example 1 is only that 8.06 g of ammonium metatungstate, 0.57 g of cerium nitrate, and 0.12 g of citric acid are dissolved in 40 g of water, and the supported silicon oxide is prepared under the same other conditions. After calculation, in the supported silicon oxide, the content of W4O 11 is 8 wt% based on silicon dioxide, the content of cerium oxide is 3 wt% based on silicon dioxide, and the balance is silicon dioxide.

[0114] Preparation of coating slurry:

[0115] Same as Example 1.

[0116] Preparation of industrial waste gas treatment catalyst:

[0117] Same as Example 1.

[0118] After calculation, in the catalyst, the supported silicon oxide is 25 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 2.3%, and CXPS / CICP = 3.5.

[0119] Example 5

[0120] Preparation of supported silicon oxide:

[0121] Same as Example 1.

[0122] Preparation of coating slurry:

[0123] The difference from Example 1 is only that 40 g of supported silicon oxide, 3 g of titanium oxide, 0.2 g of silica sol, 0.2 g of PVA, 0.1 g of nitric acid are contacted with 100 g of water,

[0124] and the slurry is prepared under the same other conditions, and the viscosity of the coating slurry is measured to be 450 mPa·s.

[0125] Preparation of industrial waste gas treatment catalyst:

[0126] Same as Example 1.

[0127] After calculation, in the catalyst, the content of supported silicon oxide is 40 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 2.3%, and CXPS / CICP = 3.2.

[0128] Example 6

[0129] Preparation of supported silicon oxide:

[0130] The same as Example 1.

[0131] Preparation of coating slurry:

[0132] The difference from Example 1 is only that 20 g of supported silicon oxide, 3 g of titanium oxide, 0.2 g of silica sol, 0.2 g of PVA, 0.1 g of nitric acid are contacted with 100 g of water.

[0133] The slurry is prepared under the condition that the remaining conditions are exactly the same, and the viscosity of the coating slurry is measured to be 400 mPa·s.

[0134] Preparation of industrial waste gas treatment catalyst:

[0135] The same as Example 1.

[0136] After calculation, in the catalyst, the content of supported silicon oxide is 20 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 2.7%, and CXPS / CICP = 3.6.

[0137] Example 7

[0138] Preparation of supported silicon oxide:

[0139] The same as Example 1.

[0140] Preparation of coating slurry:

[0141] The difference from Example 1 is only that 50 g of supported silicon oxide, 3 g of titanium oxide, 0.2 g of silica sol, 0.2 g of PVA, 0.1 g of nitric acid are contacted with 100 g of water.

[0142] The slurry is prepared under the condition that the remaining conditions are exactly the same, and the viscosity of the coating slurry is measured to be 550 mPa·s.

[0143] Preparation of industrial waste gas treatment catalyst:

[0144] The same as Example 1.

[0145] After calculation, in the catalyst, the content of supported silicon oxide is 50 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 2.8%, and CXPS / CICP = 4.1.

[0146] Example 8

[0147] Preparation of supported silicon oxide:

[0148] Same as Example 1.

[0149] Preparation of coating slurry:

[0150] The difference from Example 1 is only that 25 g of supported silicon oxide, 6 g of titanium oxide, 0.2 g of silica sol, 0.2 g of PVA, 0.1 g of nitric acid are contacted with 100 g of water.

[0151] The slurry is prepared under the condition that the remaining conditions are exactly the same, and the viscosity of the coating slurry is measured to be 360 mPa·s.

[0152] Preparation of industrial waste gas treatment catalyst:

[0153] Same as Example 1.

[0154] After calculation, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 6 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 2%, and CXPS / CICP = 3.8.

[0155] Example 9

[0156] Preparation of supported silicon oxide:

[0157] Same as Example 1.

[0158] Preparation of coating slurry:

[0159] The difference from Example 1 is only that 25 g of supported silicon oxide, 1 g of titanium oxide, 0.2 g of silica sol, 0.2 g of PVA, 0.1 g of nitric acid are contacted with 100 g of water.

[0160] The slurry is prepared under the condition that the remaining conditions are exactly the same, and the viscosity of the coating slurry is measured to be 420 mPa·s.

[0161] Preparation of industrial waste gas treatment catalyst:

[0162] Same as Example 1.

[0163] After calculation, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 1 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 2.7%, and CXPS / CICP = 3.3.

[0164] Example 10

[0165] Preparation of supported silicon oxide:

[0166] The same as in Example 1.

[0167] Preparation of coating slurry:

[0168] The difference from Example 1 is only that 25 g of supported silicon oxide, 10 g of titanium oxide, 0.2 g of silica sol, 0.2 g of PVA, 0.1 g of nitric acid are contacted with 100 g of water.

[0169] The slurry is prepared under the condition that the remaining conditions are exactly the same, and the viscosity of the coating slurry is measured to be 480 mPa·s.

[0170] Preparation of industrial waste gas treatment catalyst:

[0171] The same as in Example 1.

[0172] After calculation, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 10 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 2.6%, and CXPS / CICP = 4.

[0173] Example 11

[0174] Preparation of supported silicon oxide:

[0175] The same as in Example 1.

[0176] Preparation of coating slurry:

[0177] The difference from Example 1 is only that 25 g of supported silicon oxide, 3 g of zirconium oxide, 0.2 g of silica sol, 0.2 g of PVA, 0.1 g of nitric acid are contacted with 100 g of water.

[0178] The slurry is prepared under the condition that the remaining conditions are exactly the same, and the viscosity of the coating slurry is measured to be 415 mPa·s.

[0179] Preparation of industrial waste gas treatment catalyst:

[0180] The same as in Example 1.

[0181] Calculated, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of zirconia is 3 wt%, and the content of Pt is 0.5 wt%. Tested, the ultrasonic shedding rate is 2.2%, and CXPS / CICP = 3.4.

[0182] Example 12

[0183] Preparation of supported silicon oxide:

[0184] Same as Example 1.

[0185] Preparation of coating slurry:

[0186] The difference from Example 1 is only that 10 ml of chloroplatinic acid solution with a Pt content of 200 g / L is added again.

[0187] The slurry is prepared under the condition that the remaining conditions are exactly the same, and the viscosity of the coating slurry is measured to be 420 mPa·s.

[0188] Preparation of industrial waste gas treatment catalyst:

[0189] Same as Example 1.

[0190] Calculated, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 2 wt%. Tested, the ultrasonic shedding rate is 1.9%, and CXPS / CICP = 4.5.

[0191] Example 13

[0192] Preparation of supported silicon oxide:

[0193] Same as Example 1.

[0194] Preparation of coating slurry:

[0195] The difference from Example 1 is only that 1 ml of chloroplatinic acid solution with a Pt content of 200 g / L is added again.

[0196] The slurry is prepared under the condition that the remaining conditions are exactly the same, and the viscosity of the coating slurry is measured to be 520 mPa·s.

[0197] Preparation of industrial waste gas treatment catalyst:

[0198] Same as Example 1.

[0199] Calculated, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.2 wt%. Tested, the ultrasonic shedding rate is 2.8%, and CXPS / CICP = 2.5.

[0200] Example 14

[0201] Preparation of supported silicon oxide:

[0202] Same as Example 1.

[0203] Preparation of coating slurry:

[0204] It is only different from Example 1 in that 15 ml of chloroplatinic acid solution with a Pt content of 200 g / L is further added.

[0205] The slurry was prepared under the condition that the remaining conditions were exactly the same, and the viscosity of the coating slurry was measured to be 505 mPa·s.

[0206] Preparation of industrial waste gas treatment catalyst:

[0207] Same as Example 1.

[0208] After calculation, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.2 wt%. After detection, the ultrasonic shedding rate is 2.7%, and CXPS / CICP = 6.

[0209] Example 15

[0210] Preparation of supported silicon oxide:

[0211] Same as Example 1.

[0212] Preparation of coating slurry:

[0213] It is only different from Example 1 in that 2.5 ml of ruthenium chloride solution with a Ru content of 200 g / L is further added.

[0214] The slurry was prepared under the condition that the remaining conditions were exactly the same, and the viscosity of the coating slurry was measured to be 385 mPa·s.

[0215] Preparation of industrial waste gas treatment catalyst:

[0216] Same as Example 1.

[0217] After calculation, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 3 wt%, and the content of Ru is 2 wt%. After detection, the ultrasonic shedding rate is 2.3%, and CXPS / CICP = 3.2.

[0218] Comparative Example 1

[0219] The only difference from Example 1 is that the prepared catalyst was not subjected to a reduction operation. The results showed that the ultrasonic shedding rate was 3.5%.

[0220] Comparative Example 2

[0221] Preparation of supported silicon oxide:

[0222] It is only different from Example 1 in that lanthanum nitrate is not added, that is, the first promoter source is not used, and the supported silicon oxide is prepared under the condition that the remaining conditions are exactly the same.

[0223] Preparation of coating slurry:

[0224] The same as Example 1.

[0225] Preparation of industrial waste gas treatment catalyst:

[0226] The same as Example 1.

[0227] After calculation, in the catalyst, the content of supported silicon oxide is 25 wt%, the content of titanium oxide is 3 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 3.6%, and CXPS / CICP = 2.2.

[0228] Comparative Example 3

[0229] Preparation of supported silicon oxide:

[0230] The same as Example 1.

[0231] Preparation of coating slurry:

[0232] It is only different from Example 1 in that titanium oxide is not added, that is, the second promoter source is not used, and the supported silicon oxide is prepared under the condition that the remaining conditions are exactly the same.

[0233] Preparation of industrial waste gas treatment catalyst:

[0234] The same as Example 1.

[0235] After calculation, in the catalyst, the content of supported silicon oxide is 25 wt%, and the content of Pt is 0.5 wt%. After detection, the ultrasonic shedding rate is 3.7%, and CXPS / CICP = 2.1.

[0236] Comparative Example 4

[0237] Preparation of supported silicon oxide:

[0238] The same as Example 1.

[0239] Preparation of coating slurry:

[0240] It is only different from Example 1 in that chloroplatinic acid is not added, that is, the third promoter source is not used, and the supported silicon oxide is prepared under the condition that the remaining conditions are exactly the same.

[0241] Preparation of industrial waste gas treatment catalyst:

[0242] Same as Example 1.

[0243] After calculation, in the catalyst, the supported silicon oxide is 25 wt%, and the content of titanium oxide is 3 wt%. After detection, the ultrasonic shedding rate is 3.65%, and CXPS / CICP = 0.

[0244] Test Example 1

[0245] The catalysts prepared in the above examples and comparative examples were evaluated for catalytic reaction performance on a fixed-bed reactor catalytic reaction device under the same conditions. The reaction results are shown in Table 1. Specifically, in this test example, the waste gas containing 1000 ppm of epichlorohydrin was contacted with the catalyst for catalytic combustion. The evaluation process conditions were as follows: in an air atmosphere, the reaction pressure was 0.05 MPa - 0.1 MPa, the tail gas volume treated per gram of catalyst was 20 L per hour, and the temperature was programmed to the reaction temperature until complete conversion. The temperature increase program was as follows: from 20°C, the temperature was increased at a rate of 10°C / min to 100°C, held for 0.5 hour, then increased at a rate of 10°C / min to 150°C, held for 0.5 hour, then increased at a rate of 5°C / min to 160°C, held for 5 minutes, then increased at a rate of 5°C / min to 165°C, held for 5 minutes, then increased at a rate of 5°C / min to 170°C, held for 5 minutes, and so on until the temperature was increased to 400°C. The reaction activity of the catalyst of the present invention was evaluated based on the reaction temperature at which the oxidation tail gas components were completely converted. The lower the temperature of complete conversion, the better the performance of the catalyst. Among them, T 99 represents the reaction temperature when the purification rate of this component in the waste gas is 99%. 400(Tn) represents that the purification rate of epichlorohydrin at 400°C is n%.

[0246] Table 1

[0247] Item <![CDATA[T 99 (℃)]]> 400 (Tn) (%) Example 1 280 - Example 2 285 - Example 3 275 - Example 4 290 - Example 5 280 - Example 6 310 - Example 7 305 - Example 8 285 - Example 9 315 - Example 10 310 - Example 11 295 - Example 12 280 - Example 13 305 - Example 14 305 - Example 15 285 - Comparative Example 1 * 95 Comparative Example 2 385 - Comparative Example 3 395 - Comparative Example 4 * 85

[0248] In the above table, * indicates that this data item was not tested, and - indicates that this data item was not shown (conversion was completed before 400°C, and the conversion rate was 100%, so the data was meaningless at this time and was not shown).

[0249] It should be noted that the above-described embodiments are only used to explain the present invention and do not constitute any limitation to the present invention. The present invention has been described by referring to typical embodiments, but it should be understood that the words used therein are descriptive and explanatory words rather than limiting words. Modifications can be made to the present invention within the scope of the claims of the present invention as provided, and the present invention can be revised without departing from the scope and spirit of the present invention. Although the present invention described therein relates to specific methods, materials and embodiments, it does not mean that the present invention is limited to the specific examples disclosed therein. On the contrary, the present invention can be extended to all other methods and applications with the same functions.

Claims

1. A slurry for forming a coating, comprising: 20 to 50 parts by weight of supported silicon oxide, 1 to 10 parts by weight of a second promoter source, 0.2 to 3 parts by weight of a third promoter source, 0.5 to 2 parts by weight of an adhesive, optionally a dispersant, optionally a pH regulator, and 33.5 to 78 parts by weight of a second solvent; The supported silicon oxide includes a carrier, an active component and a first promoter component supported on the carrier, wherein the carrier includes silicon dioxide, and the active component includes W4O 11 , and the first promoter component includes a rare earth metal oxide; The second promoter source is selected from at least one of oxides of Group IVB elements; The third promoter source is selected from at least one of compounds containing Group VIIIB noble metal elements; The adhesive includes silica sol; The second solvent is water; In the supported silicon oxide, based on the total weight of the carrier, the content of the active component is 8 wt% to 24 wt%; the content of the first promoter component is 3 wt% to 12 wt%.

2. The slurry according to claim 1, wherein The first promoter component includes at least one of lanthanum oxide and cerium oxide; and / or The second promoter source is selected from at least one of titanium oxide and zirconium oxide; and / or The third promoter source is selected from at least one of chloroplatinic acid and ruthenium chloride; and / or The adhesive includes silica sol with a silica content of 20 wt% to 40 wt%; and / or The dispersant is selected from polyvinyl alcohol with a weight average molecular weight of 140,000 to 200,000; and / or The pH regulator is nitric acid; and / or The viscosity of the slurry at 25 °C is 350 to 550 mPa·s.

3. The slurry according to claim 1 or 2, characterized in that, The preparation method of the supported silicon oxide includes: S1. Mixing an active component source, a first promoter component source, an organic acid, a silicon source, and a first solvent to obtain a mixed raw material system; S2. Performing solid-liquid treatment on the mixed raw material system to obtain a solid mixture; S3. Sequentially performing drying treatment and calcination treatment on the solid mixture to obtain supported silicon oxide; In step S1, the active component source is selected from tungsten-containing compounds, and the first promoter component source is selected from rare earth metal element-containing compounds.

4. The slurry according to claim 3, wherein The active component source is selected from at least one of ammonium metatungstate, ammonium tungstate, sodium tungstate, and tungstic acid; and / or The first promoter component source is selected from at least one of lanthanum nitrate, cerium nitrate, praseodymium nitrate, and samarium nitrate; and / or The organic acid is selected from at least one of citric acid, malic acid, and oxalic acid; and / or The silicon source is silica; and / or The first solvent is water.

5. The paste according to claim 3, characterized in that, In step S1, the mixing is carried out under the condition of 40 °C to 80 °C; and / or In step S2, the solid-liquid treatment method is to evaporate the solvent; and / or In step S3, the conditions of the drying treatment include: the temperature is 90 °C to 120 °C, and the time is 6 h to 24 h; and / or the conditions of the calcination treatment include: first calcining in an air atmosphere at a temperature range of 400 °C to 600 °C for 1 h to 12 h, and then calcining in a hydrogen atmosphere at a temperature range of 200 °C to 300 °C for 1 h to 3 h.

6. The paste according to claim 5, characterized in that, In step S1, the mixing is carried out under the condition of 50 °C to 70 °C; and / or In step S2, the solid-liquid treatment is carried out in a rotary evaporator.

7. The slurry according to claim 6, wherein In step S2, the evaporation operation is carried out under the condition of 40 °C to 80 °C for the solid-liquid treatment.

8. The paste according to claim 7, wherein In step S2, the evaporation operation is carried out under the condition of 50 °C to 70 °C for the solid-liquid treatment.

9. The slurry according to claim 1 or 2, wherein In the slurry, the content of the supported silicon oxide is 25 to 40 parts by weight; and / or the content of the second auxiliary agent source is 3 to 6 parts by weight; and / or the content of the third auxiliary agent source is 0.5 to 2 parts by weight; and / or the content of the adhesive is 0.5 to 1 part by weight; and / or the content of the dispersant is 0.2 to 1 part by weight; and / or the content of the pH regulator is 0.1 to 0.5 part by weight; and / or the content of the second solvent is 50.2 to 70.7 parts by weight.

10. The paste according to claim 9, characterized in that, In the slurry, the content of the dispersant is 0.2 to 0.5 part by weight; and / or the content of the pH regulator is 0.1 to 0.3 part by weight.

11. Use of the slurry according to any one of claims 1-10 as a raw material for forming a coating on a monolithic support.

12. The application according to claim 11, characterized in that, The monolithic support includes at least one of a ceramic support and a metal support. The ceramic support is selected from honeycomb supports, and the metal support is selected from at least one of stainless steel, aluminous ferrites, and Fe-Cr-Al alloys.

13. The application according to claim 12, characterized in that, The ceramic support is selected from at least one of cordierite honeycomb supports, mullite honeycomb supports, and aluminum titanate ceramic honeycomb supports.

14. A catalyst for treating industrial waste gas, comprising: A honeycomb carrier and a coating present on the inner surface and / or outer surface of the honeycomb carrier, the coating comprising a supported silicon oxide, a second promoter, and a third promoter, wherein the second promoter is selected from at least one of the group consisting of oxides of Group IVB elements; the third promoter is selected from at least one of the group consisting of oxides of Group VIIIB noble metal elements; the supported silicon oxide comprises a carrier and an active component and a first promoter component supported on the carrier, wherein the carrier comprises silica, and the active component comprises W4O 11 , and the first promoter component comprises a rare earth metal oxide; Based on the total weight of the catalyst as the calculation basis, the content of the honeycomb support is 40wt% to 80wt%; the content of the supported silicon oxide is 20wt% to 50wt%; the content of the second auxiliary agent is 1wt% to 10wt%; the content of the third auxiliary agent is 0.2wt% to 3wt%; In the supported silicon oxide, based on the total weight of the support as the calculation basis, the content of the active component is 8wt% to 24wt%; the content of the first auxiliary agent component is 3wt% to 12wt%.

15. The catalyst according to claim 14, wherein The first auxiliary agent component includes at least one of lanthanum oxide and cerium oxide; and / or The second auxiliary agent is selected from at least one of titanium oxide and zirconium oxide; and / or The third auxiliary agent is selected from at least one of platinum oxide and ruthenium oxide.

16. The catalyst according to claim 14 or 15, characterized in that, The preparation method of the supported silicon oxide includes: S1. Mixing an active component source, a first auxiliary agent component source, an organic acid, a silicon source, and a first solvent to obtain a mixed raw material system; S2. Performing solid-liquid treatment on the mixed raw material system to obtain a solid mixture; S3. Sequentially performing drying treatment and calcination treatment on the solid mixture to obtain the supported silicon oxide; In step S1, the active component source is selected from tungsten-containing compounds, and the first auxiliary agent component source is selected from rare earth metal element-containing compounds.

17. The catalyst according to claim 16, wherein The active component source is selected from at least one of ammonium metatungstate, ammonium tungstate, sodium tungstate, and tungstic acid; and / or The first auxiliary agent component source is selected from at least one of lanthanum nitrate, cerium nitrate, praseodymium nitrate, and samarium nitrate; and / or The organic acid is selected from at least one of citric acid, malic acid, and oxalic acid; and / or The silicon source is silicon dioxide; and / or The first solvent is water.

18. The catalyst according to claim 16, wherein In step S1, the mixing is carried out under the condition of 40°C to 80°C; and / or In step S2, the way of the solid-liquid treatment is to evaporate the solvent; and / or In step S3, the conditions for the drying treatment include: temperature of 90°C to 120°C and time of 6 h to 24 h; and / or the conditions for the calcination treatment include: first calcining in an air atmosphere at a temperature range of 400°C to 600°C for 1 h to 12 h, and then calcining in a hydrogen atmosphere at a temperature range of 200°C to 300°C for 1 h to 3 h.

19. The catalyst according to claim 18, wherein In step S1, the mixing is carried out under the condition of 50°C to 70°C; and / or In step S2, the solid-liquid treatment is carried out in a rotary evaporator.

20. The catalyst according to claim 19, wherein In step S2, the evaporation operation of the solid-liquid treatment is carried out under the condition of 40°C to 80°C.

21. The catalyst according to claim 20, wherein In step S2, the evaporation operation of the solid-liquid treatment is carried out under the condition of 50°C to 70°C.

22. The catalyst according to claim 14 or 15, characterized in that, The honeycomb carrier is selected from at least one of cordierite honeycomb carriers, mullite honeycomb carriers, and aluminum titanate ceramic honeycomb carriers; and / or the third auxiliary agent satisfies CXPS / CICP = 2.5 to 6; wherein, CXPS is the molar content of the third auxiliary agent element in the catalyst characterized by X-ray photoelectron spectroscopy; CICP is the molar content of the third auxiliary agent element in the catalyst characterized by plasma coupling.

23. The catalyst according to claim 14 or 15, characterized in that, Based on the total weight of the catalyst as the calculation basis, the content of the honeycomb carrier is 45 wt% to 70 wt%; the content of the supported silicon oxide is 25 wt% to 40 wt%; the content of the second auxiliary agent is 3 wt% to 6 wt%; the content of the third auxiliary agent is 0.5 wt% to 2 wt%.

24. A method for preparing a catalyst for treating industrial waste gas, comprising: 1) Forming the slurry according to any one of claims 1-10 on a honeycomb carrier to obtain a catalyst precursor; 2) Sequentially performing a drying treatment and a calcination treatment on the catalyst precursor to obtain a catalyst.

25. The preparation method according to claim 24, wherein In step 2), the conditions for the drying treatment include: temperature of 90°C to 120°C and time of 6 h to 24 h; and / or the conditions for the calcination treatment include: temperature of 400°C to 600°C and time of 1 h to 12 h.

26. Use of the catalyst according to any one of claims 14-23 or the catalyst prepared by the preparation method according to claim 24 or 25 in the treatment of industrial waste gas.

27. The application according to claim 26, characterized in that, The industrial waste gas includes chlorine-containing industrial waste gas.

28. The application according to claim 27, wherein The chlorine-containing industrial waste gas includes epichlorohydrin.

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