Low-temperature denitration catalyst and preparation method thereof

文档序号:594203 发布日期:2021-05-28 浏览:9次 中文

阅读说明:本技术 低温脱硝催化剂及其制备方法 (Low-temperature denitration catalyst and preparation method thereof ) 是由 李慧远 伊茂广 薛志伟 李亮亮 王志民 张晓威 于 2020-12-30 设计创作,主要内容包括:本发明属于工业烟气脱硝技术领域,特别涉及一种低温脱硝催化剂及其制备方法。所述的低温脱硝催化剂是以过渡金属铈、钒、铜的卤氧化物中的一种或多种为活性组分,以钨、钼、铁的金属氧化物中的一种或多种为助催化剂,以钛白粉、硅藻土、氧化铝中的一种或多种为载体,经过极化、混料、挤出成型、干燥、烧成制备而成。本发明催化剂具有低温脱硝活性(150-250℃)、抗二氧化硫和水中毒性能,稳定性高,催化剂机械强度高等优点,适用于非电行业大气污染物治理。(The invention belongs to the technical field of industrial flue gas denitration, and particularly relates to a low-temperature denitration catalyst and a preparation method thereof. The low-temperature denitration catalyst is prepared by taking one or more of oxyhalides of transition metals of cerium, vanadium and copper as an active component, taking one or more of metal oxides of tungsten, molybdenum and iron as a cocatalyst, taking one or more of titanium dioxide, diatomite and alumina as a carrier, and carrying out polarization, mixing, extrusion molding, drying and sintering. The catalyst has the advantages of low-temperature denitration activity (150-.)

1. A low-temperature denitration catalyst is characterized in that: one or more of oxyhalides of cerium, vanadium and copper are taken as active components, one or more of metal oxides of tungsten, molybdenum and iron are taken as promoters, and one or more of titanium dioxide, diatomite and alumina are taken as carriers; based on the mass of the catalyst carrier, the mass percentage of the active component in the catalyst is 0.5-23%, and the mass percentage of the cocatalyst is 0-30%.

2. The low-temperature denitration catalyst according to claim 1, characterized in that: the oxyhalide is obtained by preparing a polarizing solution and performing supercritical treatment.

3. A method for preparing the low-temperature denitration catalyst of claim 1 or 2, characterized in that: the method comprises the following steps:

(1) preparation of polarizing liquid

Weighing halogen salt and halogen acid to prepare a polarization solution; the halogen salt is one of sodium chloride, potassium chloride, sodium fluoride, potassium fluoride, sodium bromide or potassium bromide; the halogen acid is one of hydrofluoric acid, hydrochloric acid and hydrogen bromide; the molar ratio of the halogen salt to the halogen acid is 0.1-4, and the concentration of halogen ions in the polarizing solution is 0.1-3 mol/L;

(2) preparation of oxyhalide active components

Weighing metal salt according to the molar ratio of the metal ions to the halogen ions in the polarization liquid of 0.1-1, putting the metal salt into a polytetrafluoroethylene container filled with the polarization liquid for dissolution, sealing and heating the container to enable the metal salt and the polarization liquid in the container to generate supercritical polarization, and filtering and washing the container after the container is cooled to room temperature to obtain a metal oxyhalide precursor;

(3) mixing material

Accurately weighing the carrier according to the mass ratio of the active component to the carrier, adding stearic acid, lactic acid and deionized water, and mixing for the first time; accurately weighing cocatalyst precursor metal salt and deionized water according to the mass ratio of the cocatalyst to the carrier to prepare cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and carrying out second mixing; weighing wood pulp, adding the wood pulp into deionized water, soaking, scattering, cleaning, mixing with glass fiber, and mixing for the third time; adding weighed polyoxyethylene and cellulose, and then mixing for the fourth time;

(4) extruding, drying and firing

Pre-extruding the mixed pug into blocks by an extruder, and extruding the pug into a honeycomb catalyst precursor for the second time after the pug is aged for 12 to 60 hours; drying the catalyst precursor in a drying box at 40-80 ℃ for 3-14 days; and roasting the dried catalyst precursor in a mesh belt kiln at the temperature of 400-700 ℃ for 5-40 hours to obtain the catalyst.

4. The production method according to claim 3, characterized in that: in the step (2), the metal salt is one or more of cerium nitrate, cerium chloride, ammonium metavanadate, vanadyl oxalate, copper nitrate or copper chloride.

5. The production method according to claim 3, characterized in that: in the step (2), the heating is carried out at the temperature of 120-250 ℃; the time of the supercritical polarization is 4-36 hours.

6. The production method according to claim 3, characterized in that: in the step (3), the usage amounts of stearic acid, lactic acid, wood pulp, glass fiber, polyethylene oxide and cellulose are as follows: based on the mass of the carrier, the mass percent of stearic acid is 0.5-5%, the mass percent of lactic acid is 0.5-5%, the mass percent of wood pulp is 1-10%, the mass percent of glass fiber is 1-10%, the mass percent of polyoxyethylene is 0.2-3%, and the mass percent of cellulose is 1-5%.

7. The production method according to claim 3, characterized in that: in the step (3), the promoter precursor metal salt is one or more of ammonium metatungstate, ammonium paratungstate, ammonium molybdate, ferric nitrate or ferric chloride.

8. The production method according to claim 3, characterized in that: in the step (4), the pre-extruded block has the size of 0.1, 0.05 or 0.01m3

Technical Field

The invention belongs to the technical field of industrial flue gas denitration, and particularly relates to a low-temperature denitration catalyst and a preparation method thereof.

Background

Nitrogen Oxides (NO)x) Is a main atmospheric pollutant, the mainstream technology for removing nitric oxide at present is a selective catalytic reduction technology, and the core of the technology is a denitration catalyst. With the implementation of a series of atmospheric pollutant control standards in China, the proportion of the pollution emission of coal-fired power plants is continuously reduced, the problem of atmospheric pollution in the non-electric industry is more and more prominent, and the flue gas treatment in the non-electric industry becomes an important task of the current atmospheric pollution treatment. However, the flue gas temperature of the non-electric industry is low, the components are complex, and the denitration catalyst for the power plant, which requires the flue gas temperature to be more than 300 ℃, cannot be normally used in the non-electric industry. Meanwhile, the catalyst is easy to be poisoned, the overall efficiency is low (only about 50 percent), and the service life is short (about 3 months). Therefore, a new ultralow-temperature denitration catalytic material technology is urgently needed to be provided aiming at the denitration current situation of the non-electric industry, and a comprehensive air pollution treatment task is implemented.

The existing flue gas denitration catalyst is more. Currently commercially available NH3SCR denitration catalyst predominantly V2O5-TiO2Or V2O5-WO3(MoO3)-TiO2The catalyst has high denitration activity and good sulfur resistance. However, the optimum application temperature range of the vanadium-titanium catalyst is 310-410 ℃, which cannot meet the denitration requirement of the non-electric industry.

In view of the urgent need of domestic denitration catalysts in non-electric industry, the development of a novel denitration catalyst with low-temperature activity, low cost and good stability is the key research point in the field of treatment of atmospheric pollutants in China.

Disclosure of Invention

Aiming at the current situation that the existing denitration catalyst cannot meet the requirements of the non-electric industry, the invention aims to provide the low-temperature denitration catalyst which has good low-temperature activity, low cost, high mechanical strength, good stability and strong anti-poisoning capability and can be used for treating flue gas in the non-electric industry; the invention also provides a preparation method of the compound, and the process is reasonable, simple and feasible.

In order to achieve the purpose, the invention adopts the following technical scheme:

the low-temperature denitration catalyst is prepared by taking one or more of oxyhalides of cerium, vanadium and copper as an active component, one or more of metal oxides of tungsten, molybdenum and iron as a cocatalyst, one or more of titanium dioxide, diatomite and alumina as a carrier, and performing polarization, mixing, extrusion molding, drying and sintering. Based on the mass of the catalyst carrier, the mass percentage of the active component in the catalyst is 0.5-23%, and the mass percentage of the cocatalyst is 0-30%.

Wherein:

the oxyhalide is obtained by preparing a polarizing solution and performing supercritical treatment.

The preparation method of the low-temperature denitration catalyst comprises the following steps:

(1) preparation of polarizing liquid

Weighing halogen salt and halogen acid according to a specific molar ratio to prepare a polarization solution; the halogen salt is one of sodium chloride, potassium chloride, sodium fluoride, potassium fluoride, sodium bromide and potassium bromide; the halogen acid is one of hydrofluoric acid, hydrochloric acid and hydrogen bromide; the molar ratio of the halogen salt to the halogen acid is 0.1-4, and the concentration of the halogen ions in the polarizing solution is 0.1-3 mol/L.

(2) Preparation of oxyhalide active components

Weighing quantitative metal salt according to the molar ratio of the metal ions to the halogen ions in the polarization liquid of 0.1-1, putting the metal salt into a polytetrafluoroethylene container filled with the polarization liquid, sealing the container after the metal salt is fully dissolved, heating the container to a specified temperature to enable the metal salt and the polarization liquid in the container to generate supercritical polarization, and filtering and washing the container after the container is cooled to room temperature to obtain the metal oxyhalide precursor.

(3) Mixing material

Accurately weighing a quantitative carrier according to the mass ratio of the active component to the carrier, adding stearic acid, lactic acid and a proper amount of deionized water, and mixing for the first time; accurately weighing cocatalyst precursor metal salt and a proper amount of deionized water according to the mass ratio of the cocatalyst to the carrier to prepare cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and carrying out second mixing; weighing quantitative wood pulp, adding the wood pulp into deionized water for soaking, scattering and cleaning, mixing with quantitative glass fiber, and carrying out third mixing; adding weighed polyoxyethylene and cellulose, and then mixing for the fourth time;

(4) extruding, drying and firing

Pre-extruding the mixed pug into blocks by an extruder, and performing secondary extrusion to obtain a honeycomb catalyst precursor after the pug is aged for 12-60 hours; drying the catalyst precursor in a drying box at 40-80 ℃ for 3-14 days; roasting the dried catalyst precursor in a mesh belt kiln at the temperature of 400-700 ℃ for 5-40 hours; obtaining the catalyst.

The preparation method of the low-temperature denitration catalyst provided by the invention has the following preferable parameters:

in the step (2), the metal salt is one or more of cerium nitrate, cerium chloride, ammonium metavanadate, vanadyl oxalate, copper nitrate or copper chloride.

In the step (2), the heating is carried out at the temperature of 120-250 ℃; the time of the supercritical polarization is 4-36 hours.

In the step (3), the usage amounts of stearic acid, lactic acid, wood pulp, glass fiber, polyethylene oxide and cellulose are as follows: based on the mass of the carrier, the mass percent of stearic acid is 0.5-5%, the mass percent of lactic acid is 0.5-5%, the mass percent of wood pulp is 1-10%, the mass percent of glass fiber is 1-10%, the mass percent of polyoxyethylene is 0.2-3%, and the mass percent of cellulose is 1-5%. The mass of the deionized water is proper.

In the step (3), the promoter precursor metal salt is one or more of ammonium metatungstate, ammonium paratungstate, ammonium molybdate, ferric nitrate or ferric chloride.

In the step (4), the pre-extruded block has the size of 0.1, 0.05 or 0.01m3

The low-temperature denitration catalyst provided by the invention can be used for flue gas treatment in the non-electric industry.

Compared with the prior art, the invention has the following beneficial effects:

1. according to the invention, the oxyhalide salt of metal is used as an active component, so that the sulfur poisoning resistance of the catalyst under a low-temperature condition can be effectively enhanced, and the low-temperature denitration activity of the catalyst is improved;

2. the catalyst has better denitration activity in the low-temperature range of 150 ℃ and 250 ℃, and widens the selection of the low-temperature denitration catalyst;

3. the catalyst has the advantages of simple preparation process, high mechanical strength, good low-temperature activity, strong poisoning resistance and high stability, and has a wide application prospect in the non-electric industry.

Drawings

FIG. 1 shows the denitration activity of a catalyst prepared according to an embodiment of the present invention as a function of temperature;

FIG. 2 shows SO resistance of a catalyst2And (6) testing the graph.

Detailed Description

The present invention will be further described with reference to the following examples.

Example 1

Accurately weighing quantitative sodium chloride and hydrochloric acid according to the molar ratio of the halogen salt to the halogen acid of 0.5 to prepare polarizing solution with the molar concentration of halogen ions of 0.5mol/L and the mass of 1000g, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative cerium nitrate according to the metal/halogen ion molar ratio of 0.5, putting the cerium nitrate into a polytetrafluoroethylene container filled with a polarization liquid, sealing the container after full dissolution, heating to 180 ℃, keeping the temperature for 24 hours, cooling to room temperature, and filtering and washing to obtain a cerium oxychloride precursor; accurately weighing quantitative titanium dioxide according to the mass percentage content of 10% of active components/carriers, and adding 0.5% of stearic acid, 3% of lactic acid and a proper amount of deionized water into the carriers by taking the mass of the carriers as a reference to carry out primary mixing; accurately weighing quantitative ammonium metatungstate and deionized water according to the mass percentage content of 10% of the cocatalyst/carrier to prepare cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and performing second mixing; accurately weighing 1% of wood pulp by taking the mass of a carrier as a reference, adding the wood pulp into deionized water, soaking, scattering, cleaning, and then mixing with 3%Mixing the glass fibers and then carrying out third mixing; taking the mass of the carrier as a reference, adding 0.8 percent of polyethylene oxide and 1 percent of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks with the volume of 0.1m by an extruder3The pug is aged for 24 hours and then extruded for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box for 7 days at the temperature of 60 ℃; roasting the dried catalyst precursor in a mesh belt kiln for 10 hours at 550 ℃; the catalyst was obtained, named catalyst 1.

Example 2

Accurately weighing quantitative potassium chloride and hydrochloric acid according to the molar ratio of the halogen salt to the halogen acid of 3 to prepare polarizing solution with the molar concentration of halogen ions of 0.1mol/L and the mass of 1000g, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative ammonium metavanadate according to the metal/halogen ion molar ratio of 0.25, putting the ammonium metavanadate into a polytetrafluoroethylene container filled with a polarization liquid, sealing the container after full dissolution, heating to 120 ℃, keeping the temperature for 36 hours, cooling to room temperature, and filtering and washing to obtain a vanadium oxychloride precursor; accurately weighing quantitative diatomite according to the mass percentage of 5% of the active component/carrier, and adding 1% of stearic acid, 5% of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference to carry out primary mixing; accurately weighing quantitative ammonium molybdate and deionized water according to the mass percentage of 5% of the cocatalyst/carrier to prepare a cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and performing second mixing; accurately weighing 5% of wood pulp by taking the mass of a carrier as a reference, adding the wood pulp into deionized water for soaking, scattering and cleaning, mixing with 7% of glass fiber, and then carrying out third mixing; taking the mass of the carrier as a reference, adding 2% of polyethylene oxide and 2% of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks with the volume of 0.1m by an extruder3The pug is aged for 36 hours and then extruded for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box for 14 days at 40 ℃; roasting the dried catalyst precursor in a mesh belt kiln for 25 hours at 450 ℃; the catalyst was obtained, named catalyst 2.

Example 3

Accurately weighing quantitative sodium fluoride and hydrofluoric acid according to the molar ratio of the halogen salt to the halogen acid of 2 to prepare polarizing solution with the molar concentration of 2mol/L and the mass of 1000g, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative copper nitrate according to the metal/halogen ion molar ratio of 0.75, putting the copper nitrate into a polytetrafluoroethylene container filled with a polarization liquid, sealing the container after full dissolution, heating to 210 ℃, keeping the temperature for 12 hours, cooling to room temperature, and filtering and washing to obtain a copper oxyfluoride precursor; accurately weighing quantitative alumina powder according to the mass percentage of 15% of the active component/carrier, and adding 2% of stearic acid, 4% of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference to carry out first mixing; accurately weighing quantitative ferric chloride and deionized water according to the mass percentage content of 20% of the cocatalyst/carrier to prepare a cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and performing second mixing; accurately weighing 10% of wood pulp by taking the mass of a carrier as a reference, adding the wood pulp into deionized water for soaking, scattering and cleaning, mixing with 5% of glass fiber, and then carrying out third mixing; taking the mass of the carrier as a reference, adding 3% of polyethylene oxide and 5% of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks with the volume of 0.1m by an extruder3Ageing the pug for 60 hours, and extruding the pug for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box for 10 days at 50 ℃; roasting the dried catalyst precursor in a mesh belt kiln for 40 hours at the temperature of 400 ℃; the catalyst was obtained, named catalyst 3.

Example 4

Accurately weighing quantitative sodium fluoride and hydrofluoric acid according to the molar ratio of 4 halogen salt/halogen acid to prepare polarizing solution with the molar concentration of 3mol/L and the mass of 1000g of halogen ions, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative vanadyl oxalate according to the molar ratio of metal/halogen ions of 1, putting the vanadyl oxalate into a polytetrafluoroethylene container filled with a polarizing solution, sealing the container after full dissolution, heating to 250 ℃, keeping the temperature for 8 hours, cooling to room temperature, filtering and washing to obtain vanadyl oxyfluorideA precursor; accurately weighing quantitative diatomite according to the mass percentage of 19% of the active component/carrier, and adding 5% of stearic acid, 1% of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference to carry out primary mixing; accurately weighing quantitative ferric nitrate and deionized water according to the mass percentage content of 30% of the cocatalyst/carrier to prepare a cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and carrying out the second mixing; accurately weighing 7% of wood pulp by taking the mass of a carrier as a reference, adding the wood pulp into deionized water for soaking, scattering and cleaning, mixing with 10% of glass fiber, and then carrying out third mixing; taking the mass of the carrier as a reference, adding 1.2% of polyethylene oxide and 4% of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks by an extruder, wherein the volume of each block is 0.05m3The pug is aged for 12 hours and then extruded for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box for 5 days at the temperature of 80 ℃; roasting the dried catalyst precursor in a mesh belt kiln for 5 hours at 650 ℃; the catalyst described, named catalyst 4, is obtained.

Example 5

Accurately weighing quantitative sodium bromide and hydrobromic acid according to the molar ratio of the halogen salt to the halogen acid of 0.1 to prepare a polarizing solution with the molar concentration of 1mol/L and the mass of 1000g of halogen ions, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative cerium chloride according to the metal/halogen ion molar ratio of 0.1, putting the cerium chloride into a polytetrafluoroethylene container filled with a polarization liquid, sealing the container after full dissolution, heating to 150 ℃, keeping the temperature for 16 hours, cooling to room temperature, and filtering and washing to obtain cerium oxybromide and cerium oxychloride precursors; accurately weighing quantitative titanium dioxide according to the mass percentage of 2% of the active component/carrier, adding 4% of stearic acid, 2% of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference, and mixing for the first time; accurately weighing quantitative ammonium paratungstate and deionized water according to the mass percentage of 25% of the cocatalyst/carrier to prepare cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and carrying out second mixing; based on the mass of the carrier, the method is accurateWeighing 3% of wood pulp, adding the wood pulp into deionized water, soaking, scattering, cleaning, mixing with 1% of glass fiber, and then mixing for the third time; taking the mass of the carrier as a reference, adding 0.5 percent of polyethylene oxide and 3 percent of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks by an extruder, wherein the volume of each block is 0.05m3Ageing the pug for 48 hours, and extruding the pug for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box for 3 days at 70 ℃; roasting the dried catalyst precursor in a mesh belt kiln for 30 hours at 700 ℃; the catalyst was obtained, named catalyst 5.

Example 6

Accurately weighing quantitative potassium bromide and hydrobromic acid according to the molar ratio of the halogen salt to the halogen acid of 1 to prepare a polarizing solution with the molar concentration of halogen ions of 0.25mol/L and the mass of 1000g, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative copper chloride according to the metal/halogen ion molar ratio of 0.6, putting the copper chloride into a polytetrafluoroethylene container filled with a polarization liquid, sealing the container after full dissolution, heating to 180 ℃, keeping the temperature for 4 hours, cooling to room temperature, and then filtering and washing to obtain copper oxybromide and copper oxychloride precursors; accurately weighing quantitative alumina powder according to the mass percentage of 23 percent of the active component/carrier, and adding 3 percent of stearic acid, 0.5 percent of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference to carry out first mixing; accurately weighing quantitative ammonium metatungstate and ammonium molybdate and deionized water according to the mass percentage of 15 percent of the cocatalyst/carrier to prepare cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and carrying out second mixing; accurately weighing 6% of wood pulp, adding the wood pulp into deionized water, soaking, scattering and cleaning the wood pulp, mixing the wood pulp with 3% of glass fiber, and then mixing for the third time by taking the mass of the carrier as a reference; taking the mass of the carrier as a reference, adding 0.2% of polyethylene oxide and 1% of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks by an extruder, wherein the volume of each block is 0.05m3The pug is aged for 12 hours and then extruded for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box for 11 days at 50 ℃; will be provided withRoasting the dried catalyst precursor in a mesh belt kiln for 15 hours at 500 ℃; the catalyst described, named catalyst 6, is obtained.

Example 7

Accurately weighing quantitative sodium chloride and hydrochloric acid according to the molar ratio of halogen salt to halogen acid of 4 to prepare polarizing solution with the molar concentration of halogen ions of 0.75mol/L and the mass of 1000g, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative ammonium metavanadate and cerium nitrate (the molar ratio of vanadium to cerium is 1:2) according to the molar ratio of metal/halogen ions of 0.8, putting the weighed materials into a polytetrafluoroethylene container filled with a polarization liquid, sealing the container after the materials are fully dissolved, heating the container to 150 ℃, keeping the temperature for 30 hours, cooling the container to room temperature, and then filtering and washing the container to obtain vanadium oxychloride and cerium oxychloride precursors; accurately weighing quantitative diatomite according to the mass percentage content of 0.5% of active component/carrier, adding 1% of stearic acid, 1% of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference, and mixing for the first time; accurately weighing quantitative ammonium metatungstate, ferric nitrate and deionized water according to the mass percentage of 8% of the cocatalyst/carrier to prepare cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and carrying out the second mixing; accurately weighing 3% of wood pulp by taking the mass of a carrier as a reference, adding the wood pulp into deionized water for soaking, scattering and cleaning, mixing with 3% of glass fiber, and then carrying out third mixing; taking the mass of the carrier as a reference, adding 1% of polyethylene oxide and 2% of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks with the volume of 0.01m by an extruder3The pug is aged for 24 hours and then extruded for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box at 55 ℃ for 9 days; roasting the dried catalyst precursor in a mesh belt kiln for 20 hours at the temperature of 600 ℃; the catalyst was obtained, named catalyst 7.

Example 8

Accurately weighing quantitative potassium chloride and hydrochloric acid according to the molar ratio of the halogen salt to the halogen acid of 3 to prepare polarizing solution with the molar concentration of halogen ions of 0.5mol/L and the mass of 1000g, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing and quantifying according to the metal/halogen ion molar ratio of 0.3Adding ammonium metavanadate and copper nitrate (the molar ratio of vanadium to copper is 1:2) into a polytetrafluoroethylene container filled with a polarization liquid, sealing the container after full dissolution, heating to 120 ℃, keeping the temperature for 24 hours, cooling to room temperature, and then filtering and washing to obtain copper oxychloride and a vanadium oxychloride precursor; accurately weighing quantitative titanium dioxide according to the mass percentage of 15% of the active component/carrier, and adding 1% of stearic acid, 2% of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference to carry out primary mixing; accurately weighing quantitative ammonium molybdate, ferric nitrate and deionized water according to the mass percentage of 13% of the cocatalyst/carrier to prepare a cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and carrying out second mixing; accurately weighing 7% of wood pulp by taking the mass of a carrier as a reference, adding the wood pulp into deionized water for soaking, scattering and cleaning, mixing with 3% of glass fiber, and then carrying out third mixing; taking the mass of the carrier as a reference, adding 0.5 percent of polyethylene oxide and 1 percent of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks with the volume of 0.01m by an extruder3Ageing the pug for 48 hours, and extruding the pug for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box for 13 days at the temperature of 45 ℃; roasting the dried catalyst precursor in a mesh belt kiln for 35 hours at the temperature of 400 ℃; the catalyst was obtained, named catalyst 8.

Example 9

Accurately weighing quantitative sodium bromide and hydrobromic acid according to the molar ratio of the halogen salt to the halogen acid of 0.5 to prepare a polarizing solution with the molar concentration of 1mol/L and the mass of 1000g of halogen ions, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative cerium nitrate and copper nitrate (the molar ratio of cerium to copper is 1:2) according to the molar ratio of metal/halogen ions of 0.5, putting the weighed materials into a polytetrafluoroethylene container filled with a polarization solution, sealing the container after the materials are fully dissolved, heating the container to 210 ℃, keeping the temperature for 14 hours, cooling the container to room temperature, and then filtering and washing the container to obtain cerium oxybromide and a copper oxybromide precursor; accurately weighing quantitative titanium dioxide according to the mass percentage content of 8% of active component/carrier, adding 2% of stearic acid, 1% of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference, and carrying out the first stepSecondary mixing; accurately weighing 4% of wood pulp by taking the mass of a carrier as a reference, adding the wood pulp into deionized water for soaking, scattering and cleaning, mixing with 4% of glass fiber, and then mixing for the second time; taking the mass of the carrier as a reference, adding 1.2% of polyethylene oxide and 1% of cellulose which are weighed, and then carrying out third mixing; pre-extruding the mixed pug into blocks with the volume of 0.1m by an extruder3The pug is aged for 36 hours and then extruded for the second time to form a precursor of the honeycomb catalyst; drying the catalyst precursor in a drying box at 50 ℃ for 9 days; roasting the dried catalyst precursor in a mesh belt kiln for 12 hours at 550 ℃; the catalyst was obtained, named catalyst 9.

Example 10

Accurately weighing quantitative sodium bromide and hydrochloric acid according to the molar ratio of the halogen salt to the halogen acid of 0.25 to prepare polarizing solution with the molar concentration of 1mol/L and the mass of 1000g of halogen ions, and placing the polarizing solution in a polytetrafluoroethylene container; accurately weighing quantitative cerium nitrate and vanadyl oxalate (the molar ratio of cerium to vanadium is 1:2) according to the molar ratio of metal/halogen ions of 0.75, putting the weighed materials into a polytetrafluoroethylene container filled with a polarization liquid, sealing the container after the materials are fully dissolved, heating the container to 150 ℃, keeping the temperature for 20 hours, cooling the container to room temperature, and then filtering and washing the container to obtain cerium oxychloride, vanadium oxychloride, cerium oxybromide and vanadium oxybromide precursors; accurately weighing quantitative alumina powder according to the mass percentage of 15% of the active component/carrier, and adding 2% of stearic acid, 2% of lactic acid and a proper amount of deionized water into the carrier by taking the mass of the carrier as a reference to carry out first mixing; accurately weighing quantitative ammonium metatungstate, ferric chloride and deionized water according to the mass percentage of 10% of the cocatalyst/carrier to prepare cocatalyst precursor solution, adding the cocatalyst precursor solution into the carrier subjected to the first mixing, and carrying out the second mixing; accurately weighing 3% of wood pulp by taking the mass of a carrier as a reference, adding the wood pulp into deionized water for soaking, scattering and cleaning, mixing with 1% of glass fiber, and then carrying out third mixing; taking the mass of the carrier as a reference, adding 1% of polyethylene oxide and 4% of cellulose which are weighed, and then mixing for the fourth time; pre-extruding the mixed pug into blocks with the volume of 0.01m by an extruder3Aging the pug for 12 hoursExtruding the mixture for the second time to form a honeycomb catalyst precursor; drying the catalyst precursor in a drying box for 8 days at the temperature of 60 ℃; roasting the dried catalyst precursor in a mesh belt kiln for 6 hours at 500 ℃; the catalyst was obtained, designated catalyst 10.

Catalysts 1-10 prepared according to examples 1-10, respectively at NH31:1,/NO, space velocity 10000h-1,H2O concentration 10%, oxygen 6%, SO2The denitration activity of the catalyst was tested under the simulated condition of 100ppm, and the specific results are shown in table 1 and fig. 1.

TABLE 1

The results of the crush strength tests for catalysts 1-10 are shown in table 2.

TABLE 2 compressive Strength of the catalyst

Axial compressive strength MPa Radial compressive strength MPa
National Standard catalyst requirements ≥2.0 ≥0.4
Catalyst of the invention >3.2 >1.1
Catalyst 1 3.6 1.4
Catalyst 2 3.7 1.6
Catalyst 3 3.5 1.1
Catalyst 4 3.2 1.4
Catalyst 5 3.3 1.2
Catalyst 6 3.8 1.2
Catalyst 7 3.4 1.3
Catalyst 8 3.4 1.3
Catalyst 9 3.6 1.3
Catalyst 10 3.3 1.5

Catalyst SO resistance for catalyst 2, catalyst 10 and conventional catalyst2And (6) testing. NOx: 500 ppm; SO (SO)210000 ppm; t: at 210 ℃. The test results are shown in FIG. 2.

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