CN113976102B - Low-temperature rare earth-based denitration catalyst powder and preparation method thereof - Google Patents

Low-temperature rare earth-based denitration catalyst powder and preparation method thereof Download PDF

Info

Publication number
CN113976102B
CN113976102B CN202111428930.3A CN202111428930A CN113976102B CN 113976102 B CN113976102 B CN 113976102B CN 202111428930 A CN202111428930 A CN 202111428930A CN 113976102 B CN113976102 B CN 113976102B
Authority
CN
China
Prior art keywords
precursor
rare earth
titanium dioxide
molybdenum
pipeline
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Active
Application number
CN202111428930.3A
Other languages
Chinese (zh)
Other versions
CN113976102A (en
Inventor
唐志诚
张国栋
韩维亮
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Lanzhou Institute of Chemical Physics LICP of CAS
Original Assignee
Lanzhou Institute of Chemical Physics LICP of CAS
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Lanzhou Institute of Chemical Physics LICP of CAS filed Critical Lanzhou Institute of Chemical Physics LICP of CAS
Priority to CN202111428930.3A priority Critical patent/CN113976102B/en
Publication of CN113976102A publication Critical patent/CN113976102A/en
Application granted granted Critical
Publication of CN113976102B publication Critical patent/CN113976102B/en
Active legal-status Critical Current
Anticipated expiration legal-status Critical

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/10—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of rare earths
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D53/00—Separation of gases or vapours; Recovering vapours of volatile solvents from gases; Chemical or biological purification of waste gases, e.g. engine exhaust gases, smoke, fumes, flue gases, aerosols
    • B01D53/34—Chemical or biological purification of waste gases
    • B01D53/74—General processes for purification of waste gases; Apparatus or devices specially adapted therefor
    • B01D53/86—Catalytic processes
    • B01D53/8621—Removing nitrogen compounds
    • B01D53/8625—Nitrogen oxides
    • B01D53/8628—Processes characterised by a specific catalyst
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/002—Mixed oxides other than spinels, e.g. perovskite
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/85—Chromium, molybdenum or tungsten
    • B01J23/88—Molybdenum
    • B01J23/887—Molybdenum containing in addition other metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/8871—Rare earth metals or actinides
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J23/00—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00
    • B01J23/70—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper
    • B01J23/76—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36
    • B01J23/84—Catalysts comprising metals or metal oxides or hydroxides, not provided for in group B01J21/00 of the iron group metals or copper combined with metals, oxides or hydroxides provided for in groups B01J23/02 - B01J23/36 with arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J23/889—Manganese, technetium or rhenium
    • B01J23/8898—Manganese, technetium or rhenium containing also molybdenum
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J33/00—Protection of catalysts, e.g. by coating
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/03—Precipitation; Co-precipitation
    • B01J37/031—Precipitation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/02—Impregnation, coating or precipitation
    • B01J37/03—Precipitation; Co-precipitation
    • B01J37/031—Precipitation
    • B01J37/035—Precipitation on carriers
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01J—CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOID CHEMISTRY; THEIR RELEVANT APPARATUS
    • B01J2523/00—Constitutive chemical elements of heterogeneous catalysts

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Materials Engineering (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Organic Chemistry (AREA)
  • Environmental & Geological Engineering (AREA)
  • Health & Medical Sciences (AREA)
  • Biomedical Technology (AREA)
  • Analytical Chemistry (AREA)
  • General Chemical & Material Sciences (AREA)
  • Oil, Petroleum & Natural Gas (AREA)
  • Catalysts (AREA)
  • Exhaust Gas Treatment By Means Of Catalyst (AREA)

Abstract

The invention discloses a preparation method of low-temperature rare earth-based denitration catalyst powder, which takes an industrial sulfate process titanium source as a raw material and utilizes chelation to form Me with a complete structure from rare earth lanthanum, cerium and praseodymium precursors of active species and molybdenum precursors and iron precursors 1 ‑O‑La‑O‑Ce‑O‑Pr‑O‑Me 2 The atomic cluster can effectively regulate the existing state of active species and greatly improve Pr 3+ 、Ce 3+ 、La 3+ The content of active species improves the defect sites in the atomic clusters, thereby promoting the oxidation-reduction performance and enhancing the catalytic activity of the catalyst SCR. The atomic clusters are anchored on the surface of titanium dioxide crystal grains through the charge effect by primary precipitation, the structural stability of the active component is improved, and an outer protective layer is constructed by precipitating the auxiliary agent on the outer layer of the titanium dioxide crystal by secondary precipitation, so that the water resistance and sulfur resistance of the catalyst are improved. In the working temperature range of 180-400 ℃, the NO conversion rate is higher than 90%, and the method can be used for industrial source flue gas denitration.

Description

Low-temperature rare earth-based denitration catalyst powder and preparation method thereof
Technical Field
The invention relates to a preparation method of low-temperature rare earth-based denitration catalyst powder, which is used as a honeycomb or flat plate type catalyst raw material for flue gas denitration treatment and belongs to the technical field of environmental protection.
Technical Field
Nitrogen Oxides (NO) x ) Is one of the main atmospheric pollutants causing photochemical smog, acid rain, ozone depletion and PM2.5, and poses a great hazard to the ecosystem and human life. The Selective Catalytic Reduction (SCR) is generally adopted at home and abroad as the most main nitrogen oxide removal technology, and the core of the SCR is a catalyst. The main commercial applications at present are vanadium-based catalysts (V) 2 O 5 -WO 3 /TiO 2 ) However, vanadium-based catalysts are volatile and pose a biological hazard associated with the flow of flue gases. In addition, V 2 O 5 Will convert SO into 2 Oxidation to SO 3 And the problems of catalyst poisoning and inactivation and the like are caused, so that the service life is short in the application process of low-temperature industrial flue gas denitration, and the inactivated flue gas becomes solid hazardous waste to cause secondary pollution.
Research researchers at home and abroad show that the rare earth-based denitration catalyst, particularly cerium dioxide, has good oxidation-reduction performance and good catalytic performance in SCR reaction through SCR catalyst research of nearly 30 years. However, ceria is easy to sinter, has high reaction temperature, high processing difficulty and other defects, and is not commercially processed or industrially applied at present. The light rare earth resources in China are rich, and a large number of light rare earth resources do not have a high-valued utilization approach, so that how to utilize the light rare earth to manufacture a high-performance green catalyst is an important subject of the environment-friendly industry in China.
CN111905709A discloses a mesoporous cerium-titanium-based low-temperature denitration catalyst and a preparation method thereof, wherein a rare earth cerium-titanium catalyst is prepared by a hydrothermal synthesis method, a template F127 is adopted, the molar ratio of cerium to titanium is adjusted, and the conditions of hydrothermal reaction are adjusted to form a structure with mesoporous channels.
CN111659413A discloses a low-temperature rare-earth-based sulfur-resistant water-resistant denitration catalyst and a preparation method thereof, wherein an active component comprises an alumina-ceria-manganese dioxide composite oxide, the alumina-ceria-manganese dioxide composite oxide prepared by a coprecipitation method is adopted in the rare-earth-based denitration catalyst, so that the low-temperature activity of the catalyst is higher, and an active temperature window is widened, wherein the introduction of an auxiliary agent enhances the sulfur resistance and the water resistance of the rare-earth-based catalyst, and the catalyst can be widely applied to tail gas denitration treatment of thermal power plants and cement plants.
CN103055848A discloses a rare earth doped low-temperature denitration catalyst and its preparation method, wherein the main active component is manganese oxide, the carrier is titanium dioxide, and ceria and ferric oxide are used as co-catalyst. Mn: fe: ce: ti =5, (0) - (2) 4. The denitration activity of the obtained metal oxide low-temperature catalyst can reach 80-98% within the temperature range of 140-180 ℃, and the metal oxide low-temperature catalyst has excellent sulfur resistance and water resistance.
In conclusion, the existing commercial denitration catalyst still takes the vanadium-based catalyst as the main component, and the deactivated vanadium-based catalyst is used as solid waste and seriously polluted. Some patents disclose the preparation of cerium-based denitration catalysts or manganese-based denitration catalysts, which are obtained by directly adding precursors of metal salts such as cerium nitrate into titanium dioxide and carrying out processes such as mixing, extrusion, drying, roasting and the like. However, in the process of drying and roasting the catalyst, the catalyst blank is easy to crack and collapse, so that the qualified rate of the catalyst is greatly reduced, the active components are easy to sinter, and the like, and the performance of the catalyst is poor.
Disclosure of Invention
The invention provides a preparation method of low-temperature rare earth-based denitration catalyst powder aiming at solving the problems that the existing rare earth-based denitration catalyst is weak in activity and easy to inactivate under a low-temperature condition, and is difficult to form in industrial production.
The invention relates to a preparation method of low-temperature rare earth-based denitration catalyst powder, which comprises the following steps of:
(1) The industrial sulfate process titanium source slurry is used as a raw material and enters a reaction kettle from a No. 1 pipeline.
(2) Dispersing Schiff base as a rare earth ion chelating agent in distilled water to form a rare earth ion chelating agent solution; then adding rare earth precursor to form active component solution. The Schiff base chelating agent is an organic matter containing amino o-vanillin, preferably methylamine o-vanillin and 1, 3-propane diamine o-vanillin. The rare earth precursor is one or more of a lanthanum precursor, a cerium precursor or a praseodymium precursor; the mass ratio of the Schiff base chelating agent to the rare earth precursor is 1 to 1; in the rare earth precursor, a praseodymium precursor, a cerium precursor and a lanthanum precursor are respectively measured by hexapraseodymium undecoxide, cerium dioxide and lanthanum trioxide, the industrial titanium source slurry is measured by titanium dioxide, and the mass ratio of the rare earth precursor to the titanium dioxide is 1 to 15-1. The active component solution enters the reaction kettle from a No. 2 pipeline.
(3) Dissolving a molybdenum chelating agent in distilled water to form a molybdenum chelating agent dispersion liquid, and adding a molybdenum precursor to form a molybdenum additive component solution; the molybdenum chelating agent is an organic matter containing benzoic acid or phosphabenzoic acid, preferably 1,3, 5-trimethyl-benzoic acid and phosphabenzoic acid, and the mass ratio of the molybdenum chelating agent to the molybdenum precursor is 1 to 1. The using amount of the molybdenum precursor is measured by molybdenum trioxide, the industrial titanium source slurry is measured by titanium dioxide, and the mass ratio of the molybdenum precursor to the titanium dioxide is 1; the molybdenum promoter component solution enters the reaction kettle from a No. 3 pipeline.
(4) Dissolving an iron chelating agent in distilled water to form an iron chelating agent dispersion liquid, and then adding an iron precursor to form an iron auxiliary agent component solution. The iron chelating agent is ethylenediamine tetraacetic acid, ethylenediamine and sulfosalicylic acid, and the mass ratio of the iron chelating agent to the iron precursor is 1 to 1. The using amount of an iron precursor is measured by ferric oxide, the industrial titanium source slurry is measured by titanium dioxide, and the mass ratio of the iron precursor to the titanium dioxide is (1). And the iron additive component solution enters the reaction kettle from a No. 4 pipeline.
(5) Adding the precipitant into a reaction kettle through a No. 5 pipeline, adjusting the pH value of the mixed slurry to 7.1 to 11.0, controlling the reaction temperature to 15 to 100 ℃, controlling the pressure to 101 to 1010kPa, and reacting for 2 to 4 hours.
(6) And dissolving the transition metal precursor in distilled water to form a transition metal auxiliary agent component solution. The transition metal precursor is one or more of a tungsten precursor, a zirconium precursor, a tin precursor, a nickel precursor, a copper precursor and a manganese precursor. Wherein the tungsten precursor is measured by tungsten trioxide, the industrial titanium source slurry is measured by titanium dioxide, and the mass ratio of the tungsten precursor to the titanium dioxide is (0.1) - (6.0); the mass ratio of the zirconium precursor to the titanium dioxide is 0.1 to 100.0; the mass ratio of the tin precursor to the titanium dioxide is 0.1 to 100.0; the mass ratio of the nickel precursor to the titanium dioxide is (0.1) - (100.0); the mass ratio of the copper precursor to the titanium dioxide is 0.1 to 100.0; the mass ratio of the manganese precursor to the titanium dioxide is 0.1 to 10.0. The transition metal additive component solution enters the reaction kettle from the No. 6 pipeline.
(7) Adding the precipitator into the reaction kettle through a No. 5 pipeline, adjusting the pH value of the mixed slurry to 7.1-11.0 again, controlling the reaction temperature to 15-100 ℃, controlling the pressure to 101-1010 kPa, and reacting for 2-4h; the precipitant used for adjusting the pH value is one or more of hexamethyl tetraethyl amine, ammonia water, n-butylamine, triethylamine, sodium hydroxide and ammonium carbonate.
(8) And (3) filtering the product obtained by the reaction to obtain a filter cake, drying and roasting the filter cake in a rotary kiln, and crushing the product by high-speed gas to obtain the low-temperature high-efficiency denitration catalyst powder. The drying temperature is controlled to be 120 to 400 ℃, the baking temperature is controlled to be 400 to 650 ℃, and the discharging time is controlled to be 30 to 240min/t; the particle size distribution D50 of the catalyst powder is within the range of 0.9 to 1.2um, and the specific surface area is 70 to 140 m 2 In the range of/g.
The industrial titanium source, the praseodymium precursor, the cerium precursor, the lanthanum precursor, the molybdenum precursor, the iron precursor, the tungsten precursor, the zirconium precursor, the tin precursor, the nickel precursor, the copper precursor and the manganese precursor are common raw materials for preparing industrial catalysts in the prior art, and the technical indexes and the usage amount of the raw materials can select corresponding raw materials and usage amounts according to actual process conditions and equipment characteristics, which are not particularly limited in the invention.
The adding sequence of the No. 1, 2, 3, 4, 5 and 6 pipeline materials can be adjusted according to the actual situation according to the particle size and catalytic performance requirements of the catalyst powder.
2. Structure of catalyst powder
FIG. 1 is an X-ray transmission characterization of a catalyst prepared according to the present invention. As can be seen from FIG. 1, the active ingredient is mainly LaCePrO x The molybdenum and the iron components are dispersed in the catalyst in the form of atomic clusters to form Me 1 -O-La-O-Ce-O-Pr-O-Me 2 The structure greatly enhances the charge flow effect in the catalyst, thereby improving the oxidation-reduction performance of the catalyst and realizing the stable and efficient operation of SCR reaction of the rare earth-based atomic cluster under the low-temperature condition. Forming an outer protective layer on the surface of the catalyst by secondary precipitation, and preferentially mixing the outer auxiliary agent with water and SO 2 The reaction plays a role in protecting the active center of the catalyst, and the water resistance and sulfur resistance of the catalyst are greatly improved.
3. Evaluation of Activity of catalyst powder
1. The evaluation method comprises the following steps: 0.6g of catalyst with the screened particle size of 20-40 meshes is uniformly mixed with 0.5g of quartz sand, and the reaction conditions are as follows: 1000 ppm NH 3 + 1000 ppm NO + 500 ppm SO 2 + 5v. % H 2 O + 5% O 2 ，N 2 As balance gas, the space velocity is 60000 h -1 The reaction activity of the catalyst is judged according to the NO conversion rate, and the product is analyzed by a KM9506 smoke analyzer.
2. And (4) evaluation results: the catalyst powder prepared by the invention has the NO conversion rate higher than 90% in a working temperature range of 180-400 ℃, has the denitration rate of 97% at 200 ℃, shows excellent catalytic activity and anti-poisoning performance at low temperature, can replace the existing low-temperature vanadium-based denitration catalyst, and is used for fixed source denitration of industrial devices.
In summary, the present invention has the following advantages over the prior art:
(1) Effectively adjust the existing state of active species and greatly improve Pr 3+ 、Ce 3+ 、La 3+ Content of active species, active component is mainly LaCePrO x The atomic cluster exists in a form, so that the defect sites in the atomic cluster are greatly improved, the oxidation-reduction performance is promoted, and the catalytic activity of the catalyst SCR is enhanced. The research team discovers that Pr is generated in the SCR reaction process in the basic and application research process 3+ And Pr 4+ 、Ce 4+ And Ce 3+ During the interconversion process, the oxidation of NO to NO is facilitated 2 And the rapid SCR reaction is promoted to be carried out. Therefore, by greatly increasing the Pr inside the catalyst 3+ 、Ce 3+ 、La 3+ Species content can effectively improve the low-temperature rapid SCR reaction efficiency;
(2) Through a chelation reaction, species such as hexapraseodymium undecanoxide, cerium dioxide, lanthanum trioxide, ferric oxide, molybdenum trioxide and the like are dispersed in the catalyst in an atomic cluster form, so that the dispersing performance of active species of the catalyst is greatly improved, and the active species and the auxiliary agent form Me 1 -O-La-O-Ce-O-Pr-O-Me 2 The cluster structure greatly enhances the charge flow effect in the catalyst, thereby improving the oxidation-reduction performance of the catalyst and realizing the stable and efficient operation of the SCR reaction of the rare earth oxide cluster under the low-temperature condition;
(3) In the production process of catalyst powder, the rare earth elements are precipitated in situThe catalyst activity is obviously enhanced by being precipitated in the carrier nano particles. In the industrial sulfate process titanium source, a large number of defect sites exist on the surface of titanium dioxide crystal grains to form Ti 3+ Ionic, readily binding to the active species LaCePrO x The atomic clusters are anchored on the surface of titanium dioxide crystal grains through the action of charges, the structural stability of active components is improved, the stable existence of rare earth-based active species in the catalyst is ensured from the source, the rare earth-based active species are difficult to sinter even being calcined at 600 ℃, and the rare earth-based active species are ensured to exist in the form of the atomic clusters all the time, so the thermal stability of the catalyst is greatly improved;
(4) An outer protective layer is constructed by precipitating the auxiliary agent on the outer layer of the titanium dioxide crystal through secondary precipitation, and the water resistance and the sulfur resistance of the catalyst are improved through the outer protective layer. After the primary precipitation, other auxiliary agents such as Zr 4+ 、Sn 4+ And the secondary precipitation is carried out on the surface of the catalyst under the action of a precipitator to form an outer protection layer, and the outer protection layer is preferentially mixed with water and SO by utilizing an outer layer auxiliary agent 2 The reaction plays a role in protecting the active center of the catalyst, and the water resistance and sulfur resistance of the catalyst are greatly improved;
(5) The method can be combined with the existing titanium dioxide production process to industrially produce low-temperature high-efficiency rare earth-based denitration catalyst powder, active components or auxiliaries are not required to be added in the subsequent catalyst forming and processing process to form a green production process of the catalyst, the emission of carbon dioxide and other pollutants is greatly reduced, the forming rate of the honeycomb catalyst or plate catalyst prepared by using the catalyst powder produced by the method is high, the qualification rate of final products can reach more than 99%, and the method has good economic benefits.
Drawings
FIG. 1 shows X-ray transmission characteristics of a low-temperature rare earth-based denitration catalyst powder.
Detailed Description
The preparation and performance of the low-temperature rare earth-based denitration catalyst of the present invention will be further described by the following specific examples.
Example 1
(1) Taking an industrial sulfate process titanium source as a raw material, metering the mass of titanium dioxide (the same below), adding 100 parts of titanium source slurry into a reaction kettle from a No. 1 pipeline at a constant speed, and stirring at a constant speed;
(2) Adding 2 parts of methylamine o-vanillin into distilled water, adding 3 parts of lanthanum nitrate, 6 parts of cerium nitrate and 1 part of praseodymium nitrate into the distilled water to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 2 pipeline;
(3) Adding 0.3 part of benzoic acid into distilled water, adding 2 parts of ammonium molybdate to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 3 pipeline;
(4) Adding 0.6 part of ethylenediamine tetraacetic acid into distilled water, adding 3 parts of ferric nitrate to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 4 pipeline;
(5) Adding ammonia water into a reaction kettle through a No. 5 pipeline, adjusting the pH value of the slurry to 7.1, controlling the reaction temperature to be 15 ℃ and the pressure to be 101kPa, and reacting for 2 hours;
(6) Adding 1 part of manganese nitrate into distilled water, and feeding the mixture into a reaction kettle from a No. 6 pipeline;
(7) Adding ammonia water into the reaction kettle again through a No. 5 pipeline, adjusting the pH value of the slurry to 8.0, controlling the reaction temperature to be 15 ℃ and the pressure to be 101kPa, and reacting for 4 hours;
(8) Filtering the reaction product by a filter to obtain a filter cake, drying and roasting the filter cake in a rotary kiln at the drying temperature of 300 ℃ and 550 ℃, and discharging after 240 min; and crushing a product obtained by roasting to obtain low-temperature denitration catalyst powder which is marked as CAT-1. The catalyst comprises the following components: the content of titanium dioxide is 83.98%, the content of rare earth oxide is 9.12%, the content of molybdenum trioxide is 3.11%, the content of ferric oxide is 2.67%, and the content of manganese dioxide is 1.12%. The specific surface area of the catalyst powder was 76 m 2 G, D50 is 0.98 um. The denitration rate and sulfur resistance of the catalyst are shown in tables 1 and 2.
Example 2
(1) Taking an industrial sulfuric acid process titanium source as a raw material, adding 100 parts of titanium source slurry into a reaction kettle from a No. 1 pipeline at a constant speed, and stirring at a constant speed;
(2) Adding 0.6 part of phosphabenzoic acid into distilled water, adding 4 parts of ammonium molybdate to form mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 3 pipeline;
(3) Adding 0.7 part of sulfosalicylic acid into distilled water, adding 4 parts of ferric nitrate to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 4 pipeline;
(4) Adding 6 parts of 1, 3-propane diamine o-vanillin into distilled water, adding 0.8 part of lanthanum nitrate, 8.2 parts of cerium nitrate and 1.6 parts of praseodymium nitrate into the distilled water to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 2 pipeline;
(5) Adding a hexamethyl tetraethyl amine solution into a reaction kettle through a No. 5 pipeline, adjusting the pH value of the slurry to 9.0, controlling the reaction temperature to be 40 ℃ and the pressure to be 101kPa, and reacting for 2 hours;
(6) Adding 2 parts of zirconium nitrate and 1 part of nickel nitrate into distilled water, and feeding the mixture into a reaction kettle from a No. 6 pipeline;
(7) Adding the hexamethyl-tetraethyl amine solution into the reaction kettle through a No. 5 pipeline again, adjusting the pH value of the slurry to 9.0, controlling the reaction temperature to be 40 ℃ and the pressure to be 101kPa, and reacting for 4 hours;
(8) Filtering the reaction product by a filter to obtain a filter cake, feeding the filter cake into a rotary kiln for drying and roasting at the drying temperature of 380 ℃ and the roasting temperature of 500 ℃, and discharging after 180 min; and crushing a product obtained by roasting to obtain low-temperature denitration catalyst powder which is marked as CAT-2. The prepared catalyst comprises the following components: 80.83 percent of titanium dioxide, 10.08 percent of rare earth oxide, 3.86 percent of molybdenum trioxide, 3.21 percent of ferric oxide, 1.36 percent of zirconium dioxide and 0.66 percent of nickel oxide. The specific surface area is 88 m 2 G, D50 is 1.02 um. The denitration rate and the sulfur resistance of the catalyst are shown in tables 1 and 2.
Example 3
(1) Taking an industrial sulfuric acid process titanium source as a raw material, adding 100 parts of titanium source slurry into a reaction kettle from a No. 1 pipeline at a constant speed, and stirring at a constant speed;
(2) Adding 4.9 parts of benzoic acid into distilled water, adding 5 parts of ammonium molybdate to form mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 3 pipeline;
(3) Adding 3.6 parts of 1, 3-propane diamine o-vanillin into distilled water, adding 6.3 parts of lanthanum nitrate and 3 parts of cerium nitrate into the distilled water to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 2 pipeline;
(4) Adding 6.6 parts of sulfosalicylic acid into distilled water, adding 7 parts of ferric nitrate to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 4 pipeline;
(5) Adding n-butylamine into a reaction kettle through a No. 5 pipeline, adjusting the pH value of the slurry to 10.9, controlling the reaction temperature to be 20 ℃, controlling the pressure to be 202kPa, and reacting for 4 hours;
(6) Adding 1 part of ammonium metatungstate, 1 part of zirconium oxychloride precursor, 1 part of stannous chloride, 1 part of nickel sulfate, 1 part of copper chloride and 1 part of manganese acetate into distilled water, and feeding the mixture into a reaction kettle from a No. 6 pipeline;
(7) Adding n-butylamine into the reaction kettle through a No. 5 pipeline again, adjusting the pH value of the slurry to 10.0, controlling the reaction temperature to be 20 ℃, controlling the pressure to be 202kPa, and reacting for 4 hours;
(8) Filtering the reaction product by a filter to obtain a filter cake, feeding the filter cake into a rotary kiln for drying and roasting at the drying temperature of 320 ℃ and 520 ℃, and discharging after 200 min; and crushing the roasted product to obtain low-temperature denitration catalyst powder which is marked as CAT-3. The catalyst comprises the following components: 73.53% of titanium dioxide, 11.36% of rare earth oxide, 4.67% of molybdenum trioxide, 5.98% of ferric oxide, 0.68% of tungsten trioxide, 0.45% of zirconium dioxide, 0.67% of tin dioxide, 0.98% of nickel oxide, 0.66% of copper oxide and 1.02% of manganese dioxide. The specific surface area is 99 m 2 (iv)/g, D50 is 1.13 um. The denitration rate and the sulfur resistance of the catalyst are shown in tables 1 and 2.
Example 4
(1) Taking an industrial sulfuric acid process titanium source as a raw material, adding 100 parts of titanium source slurry into a reaction kettle from a No. 1 pipeline at a constant speed, and stirring at a constant speed;
(2) Adding 2 parts of methylamine o-vanillin into distilled water, adding 9 parts of cerium sulfate and 1 part of praseodymium nitrate to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 2 pipeline;
(3) Adding 0.1 part of benzoic acid into distilled water, adding 1 part of ammonium molybdate to form mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 3 pipeline;
(4) Adding 0.2 part of ethylenediamine into distilled water, adding 1 part of ferric nitrate into the distilled water to form mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 4 pipeline;
(5) Adding ammonia water into a reaction kettle through a No. 5 pipeline, adjusting the pH value of the slurry to 9.0, controlling the reaction temperature to be 80 ℃ and the pressure to be 101kPa, and reacting for 3 hours;
(6) Adding 1 part of copper nitrate into distilled water, and feeding the mixture into a reaction kettle from a No. 6 pipeline;
(7) Adding ammonia water into the reaction kettle through a No. 5 pipeline again, adjusting the pH value of the slurry to 9.0, controlling the reaction temperature to be 80 ℃ and the pressure to be 101kPa, and reacting for 3 hours;
(8) Filtering the reaction product by a filter to obtain a filter cake, feeding the filter cake into a rotary kiln for drying and roasting, wherein the drying temperature is 300 ℃, roasting is carried out at 510 ℃, and discharging is carried out after 160 min; and crushing a product obtained by roasting to obtain low-temperature denitration catalyst powder which is marked as CAT-4. The catalyst comprises the following components: the content of titanium dioxide is 81.31 percent, the content of rare earth oxide is 14.62 percent, the content of molybdenum trioxide is 1.68 percent, the content of ferric oxide is 1.76 percent, and the content of copper oxide is 0.63 percent; the specific surface area is 112 m 2 (iv)/g, D50 is 1.08 um; the denitration rate and the sulfur resistance of the catalyst are shown in tables 1 and 2.
Example 5
(1) Taking an industrial sulfuric acid process titanium source as a raw material, adding 100 parts of titanium source slurry into a reaction kettle from a No. 1 pipeline at a constant speed, and stirring at a constant speed;
(2) Adding 2 parts of 1, 3-propane diamine o-vanillin into distilled water, adding 6 parts of cerium nitrate to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 2 pipeline;
(3) Adding 0.3 part of 1,3, 5-trimethyl-benzoic acid into distilled water, adding 2 parts of ammonium molybdate to form mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 3 pipeline;
(4) Adding 0.6 part of sulfosalicylic acid into distilled water, adding 1 part of ferric nitrate to form mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 4 pipeline;
(5) Adding sodium hydroxide into a reaction kettle through a No. 5 pipeline, adjusting the pH value of the slurry to 9.0, controlling the reaction temperature to be 15 ℃ and the pressure to be 101kPa, and reacting for 2 hours;
(6) Adding 1 part of ammonium paratungstate into distilled water, and feeding the mixture into a reaction kettle from a No. 6 pipeline;
(7) Adding sodium hydroxide into the reaction kettle again through a No. 5 pipeline, adjusting the pH value of the slurry to 10.0, controlling the reaction temperature to be 15 ℃ and the pressure to be 101kPa, and reacting for 2 hours;
(8) Filtering the reaction product by a filter to obtain a filter cake, feeding the filter cake into a rotary kiln for drying and roasting, wherein the drying temperature is 200 ℃, roasting is carried out at 550 ℃, and discharging is carried out after 200 min; and crushing a product obtained by roasting to obtain low-temperature denitration catalyst powder which is marked as CAT-5. The catalyst comprises the following components: 82.40% of titanium dioxide, 14.96% of rare earth oxide, 1.23% of molybdenum trioxide, 0.85% of ferric oxide and 1.46% of tungsten trioxide; the specific surface area is 134 m 2 G, D50 is 1.12 um; the denitration rate and sulfur resistance of the catalyst are shown in tables 1 and 2.
Example 6
(1) Taking an industrial sulfuric acid process titanium source as a raw material, adding 100 parts of titanium source slurry into a reaction kettle from a No. 1 pipeline at a constant speed, and stirring at a constant speed;
(2) Adding 2 parts of methylamine o-vanillin into distilled water, adding 3 parts of lanthanum nitrate, 3.6 parts of cerium phosphate and 4 parts of praseodymium nitrate to form a mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 2 pipeline;
(3) Adding 2.2 parts of sulfosalicylic acid into distilled water, adding 6 parts of ferric nitrate to form mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 4 pipeline;
(4) Adding 1.6 parts of phosphabenzoic acid into distilled water, adding 6 parts of ammonium molybdate to form mixed liquid, and feeding the mixed liquid into a reaction kettle from a No. 3 pipeline;
(5) Adding ammonium carbonate into a reaction kettle through a No. 5 pipeline, adjusting the pH value of the slurry to 9.0, controlling the reaction temperature to be 25 ℃ and the pressure to be 202kPa, and reacting for 2 hours;
(6) Adding 3 parts of nickel nitrate into distilled water, and feeding the mixture into a reaction kettle from a No. 6 pipeline;
(7) Adding ammonium carbonate into the reaction kettle through a No. 5 pipeline again, adjusting the pH value of the slurry to 10.0, controlling the reaction temperature to be 25 ℃ and the pressure to be 202kPa, and reacting for 3 hours;
(8) Filtering the reaction product to obtain a filter cakeDrying and roasting the filter cake in a rotary kiln at the drying temperature of 450 ℃ and 600 ℃, and discharging after 200 min; and crushing a product obtained by roasting to obtain low-temperature denitration catalyst powder which is marked as CAT-6. The catalyst comprises the following components: 76.29 percent of titanium dioxide, 12.16 percent of rare earth oxide, 5.13 percent of molybdenum trioxide, 4.53 percent of ferric oxide and 1.89 percent of nickel oxide; the specific surface area is 106 m 2 (iv)/g, D50 is 1.09 um; the denitration rate and the sulfur resistance of the catalyst are shown in tables 1 and 2.
Comparative example 1
600kg of industrial titanium dioxide is weighed, 200L of distilled water is added for mixing, 387.3kg of cerium sulfate is dissolved in 178.8L of distilled water, 159.4kg of ammonium molybdate is dissolved in 39.9L of distilled water, 109.1kg of zirconium nitrate is dissolved in 104.5L of distilled water, 103.7kg of stannic chloride is dissolved in 51.9L of distilled water, 110.9kg of manganese acetate is dissolved in 55.4L of distilled water, the five solutions are mixed and added into the titanium dioxide for mixing for 8h, and the rare earth-based denitration catalyst powder is obtained by roasting, crushing and grinding at 650 ℃. The catalyst is denoted DB-1. The denitration rate and sulfur resistance of the catalyst are shown in tables 1 and 2.
Comparative example 2
Weighing 1000kg of industrial titanium dioxide, adding 200L of distilled water, mixing, dissolving 99.7kg of cerium nitrate and 43.2kg of lanthanum nitrate in 70.5L of distilled water, dissolving 11.3 kg of ferric nitrate in 22.5L of distilled water, and dissolving 1.4kg of manganese nitrate in 2.8L of distilled water, and recording the solution as D; the three solutions are mixed and added into titanium dioxide to be mixed for 4h, and the mixture is roasted, crushed and ground at the temperature of 400 ℃ to obtain the rare earth-based denitration catalyst powder. The catalyst is denoted DB-2. The denitration rate and sulfur resistance of the catalyst are shown in tables 1 and 2.
Figure DEST_PATH_IMAGE001
As can be seen from Table 1, the denitration performance of the catalysts prepared in examples 1-6 is better than that of comparative examples 1 and 2, the denitration rate is more than 90% at 180-400 ℃, the denitration rate is kept above 90% at 200 ℃, and the SCR performance is good.
Figure DEST_PATH_IMAGE002
As can be seen from the table 2, the water resistance and sulfur resistance of the catalysts prepared in the examples 1 to 6 are superior to those of the comparative examples 1 and 2, the denitration rate is kept above 90% at the temperature of 200 ℃, and the SCR performance is good.

Claims (3)

1. A preparation method of low-temperature rare earth-based denitration catalyst powder comprises the following steps:
(1) Taking industrial sulfate process titanium source slurry as a raw material, and feeding the raw material into a reaction kettle from a No. 1 pipeline;
(2) Dispersing Schiff base as a rare earth ion chelating agent in distilled water to form a rare earth ion chelating agent solution; adding a rare earth precursor to form an active component solution, and feeding the active component solution into the reaction kettle from a No. 2 pipeline; the rare earth ion chelating agent is methylamine o-vanillin and 1, 3-propane diamine o-vanillin, and the mass ratio of the rare earth ion chelating agent to the rare earth precursor is 1 to 1; the rare earth precursor is one or more of a lanthanum precursor, a cerium precursor or a praseodymium precursor; in the rare earth precursor, a praseodymium precursor, a cerium precursor and a lanthanum precursor are respectively measured by hexapraseodymium undecoxide, cerium dioxide and lanthanum trioxide, the industrial titanium source slurry is measured by titanium dioxide, and the mass ratio of the rare earth precursor to the titanium dioxide is 1 to 15: 1;
(3) Dissolving a molybdenum chelating agent in distilled water to form a molybdenum chelating agent dispersion liquid, adding a molybdenum precursor to form a molybdenum auxiliary agent component solution, and feeding the molybdenum auxiliary agent component solution into a reaction kettle from a No. 3 pipeline; the molybdenum chelating agent is 1,3, 5-trimethyl-benzoic acid, the mass ratio of the molybdenum chelating agent to the molybdenum precursor is 1 to 1, the usage amount of the molybdenum precursor is measured by molybdenum trioxide, the industrial titanium source slurry is measured by titanium dioxide, and the mass ratio of the molybdenum precursor to the titanium dioxide is 1 to 10 to 1;
(4) Dissolving an iron chelating agent in distilled water to form an iron chelating agent dispersion liquid, adding an iron precursor to form an iron auxiliary agent component solution, and feeding the iron auxiliary agent component solution into a reaction kettle from a No. 4 pipeline; the iron chelating agent is ethylenediamine tetraacetic acid, ethylenediamine or sulfosalicylic acid, and the mass ratio of the iron chelating agent to the iron precursor is 1 to 1; the usage amount of the iron precursor is measured by ferric oxide, the industrial titanium source slurry is measured by titanium dioxide, and the mass ratio of the iron precursor to the titanium dioxide is (1);
(5) Adding the precipitant into a reaction kettle through a No. 5 pipeline, adjusting the pH value of the mixed slurry to 7.1 to 11.0, controlling the reaction temperature to 15 to 100 ℃, controlling the pressure to 101 to 1010kPa, and reacting for 2 to 4 hours;
(6) Dissolving a transition metal precursor in distilled water to form a transition metal auxiliary agent component solution, and feeding the transition metal auxiliary agent component solution into a reaction kettle from a No. 6 pipeline; the transition metal precursor is one or more of a tungsten precursor, a zirconium precursor, a tin precursor, a nickel precursor, a copper precursor and a manganese precursor, the tungsten precursor is measured by tungsten trioxide, the industrial titanium source slurry is measured by titanium dioxide, and the mass ratio of the tungsten precursor to the titanium dioxide is (0.1) - (6.0); the mass ratio of the zirconium precursor to the titanium dioxide is 0.1 to 100.0; the mass ratio of the tin precursor to the titanium dioxide is 0.1 to 100.0; the mass ratio of the nickel precursor to the titanium dioxide is 0.1 to 100.0; the mass ratio of the copper precursor to the titanium dioxide is 0.1 to 100.0; the mass ratio of the manganese precursor to the titanium dioxide is (0.1) - (100: 10.0);
(7) Adding the precipitator into the reaction kettle through a No. 5 pipeline, adjusting the pH value of the mixed slurry to 7.1-11.0 again, controlling the reaction temperature to 15-100 ℃, controlling the pressure to 101-1010 kPa, and reacting for 2-4h;
(8) And (3) filtering the product obtained by the reaction to obtain a filter cake, drying and roasting the filter cake in a rotary kiln, and crushing the product by high-speed gas to obtain the low-temperature high-efficiency denitration catalyst powder.
2. The method for preparing the low-temperature rare-earth-based denitration catalyst powder as claimed in claim 1, wherein: in the steps (5) and (7), the precipitant used for adjusting the pH value is one or more of hexamethyl tetraethyl amine, ammonia water, n-butyl amine, triethylamine, sodium hydroxide and ammonium carbonate.
3. The method for preparing the low-temperature rare-earth-based denitration catalyst powder as claimed in claim 1, wherein: in the step (8), the drying temperature is controlled to be 120 to 400 ℃, the baking temperature is controlled to be 400 to 650 ℃, and the discharging time is controlled to be 30 to 240min/t.
CN202111428930.3A 2021-11-29 2021-11-29 Low-temperature rare earth-based denitration catalyst powder and preparation method thereof Active CN113976102B (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN202111428930.3A CN113976102B (en) 2021-11-29 2021-11-29 Low-temperature rare earth-based denitration catalyst powder and preparation method thereof

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN202111428930.3A CN113976102B (en) 2021-11-29 2021-11-29 Low-temperature rare earth-based denitration catalyst powder and preparation method thereof

Publications (2)

Publication Number Publication Date
CN113976102A CN113976102A (en) 2022-01-28
CN113976102B true CN113976102B (en) 2023-03-10

Family

ID=79732363

Family Applications (1)

Application Number Title Priority Date Filing Date
CN202111428930.3A Active CN113976102B (en) 2021-11-29 2021-11-29 Low-temperature rare earth-based denitration catalyst powder and preparation method thereof

Country Status (1)

Country Link
CN (1) CN113976102B (en)

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN106964394A (en) * 2017-04-26 2017-07-21 武汉理工大学 It is a kind of for bar shaped iron-based molecular sieve catalyst of denitrating flue gas and preparation method thereof
CN108745345A (en) * 2018-06-20 2018-11-06 杭州同久净颢科技有限责任公司 A kind of no vanadium denitration catalyst and preparation method thereof
CN111530475B (en) * 2020-05-18 2023-03-31 中国科学院兰州化学物理研究所 Rare earth-based medium-low temperature denitration catalyst powder and preparation method thereof
CN111659413A (en) * 2020-07-14 2020-09-15 无锡威孚环保催化剂有限公司 Low-temperature rare earth-based sulfur-resistant water-resistant denitration catalyst and preparation method thereof
CN112473688A (en) * 2020-11-26 2021-03-12 西安科技大学 Preparation method of rare earth chelated vanadium low-cost wide-temperature-window denitration catalyst
CN113318729B (en) * 2021-07-06 2022-10-04 中国科学院兰州化学物理研究所 Preparation method of high-airspeed and poisoning-resistant rare earth-based denitration catalyst powder

Also Published As

Publication number Publication date
CN113976102A (en) 2022-01-28

Similar Documents

Publication Publication Date Title
CN105561983B (en) A kind of Mn-Ce support types low-temperature denitration catalyst and preparation method thereof
CN101920213B (en) Low temperature SCR denitration catalyst taking organic metal framework as carrier and preparation method thereof
CN105854873B (en) A kind of composite oxide of metal denitrating catalyst of efficient cryogenic and preparation method thereof
CN102294273B (en) Preparation method for TiO2-WO3 composite powder used as catalyst carrier
CN102327783B (en) Method for preparing denitration catalyst carrier TiO2-WO3 composite powder
CN106732751B (en) Desulfurization and denitrification catalyst, and preparation method and use method thereof
CN111530475B (en) Rare earth-based medium-low temperature denitration catalyst powder and preparation method thereof
CN104162421A (en) Preparation method of high temperature resistant vanadium tungsten titanium oxide catalyst
CN103846083A (en) Tungsten titanium composite oxide supported cerium oxide catalyst, preparation method as well as application of catalyst
CN102583522A (en) Preparation method for titanium dioxide serving as catalyst carrier
CN106076316A (en) A kind of with method that metatitanic acid is the raw material wide operating temperature denitrating catalyst of preparation
CN104056619A (en) Method for modifying photocatalyst TiO2 by using WO3 and rare earth metal element La
CN103769083A (en) Efficient denitration composite oxide catalyst as well as preparation method and application thereof
CN108212180A (en) A kind of middle low temperature SCR denitration titanium molybdenum composite powder and preparation method thereof
CN107029739A (en) A kind of preparation method and application without low temperature SCR denitration catalyst in vanadium
CN105903478B (en) Medium-low temperature SCR catalyst with wider use temperature and preparation method thereof
CN104607198A (en) Vanadium-free plate-like denitration catalyst and preparation method thereof
CN108311134B (en) Titanium-tungsten-silicon composite powder for SCR denitration of diesel vehicle/ship tail gas and preparation method thereof
CN109745995B (en) Wide-temperature-window SCR flue gas denitration catalyst and preparation method and application thereof
CN113976102B (en) Low-temperature rare earth-based denitration catalyst powder and preparation method thereof
CN105664917A (en) Layered structure cerium based oxide catalyst, preparation method and application thereof
CN112121816A (en) Low-temperature catalyst special for waste incineration
CN113318729B (en) Preparation method of high-airspeed and poisoning-resistant rare earth-based denitration catalyst powder
CN111167433A (en) Preparation method of cerium-tin composite oxide SCR denitration catalyst and catalyst
CN107913695B (en) Heavy metal deposition-resistant denitration catalyst and preparation method thereof

Legal Events

Date Code Title Description
PB01 Publication
PB01 Publication
SE01 Entry into force of request for substantive examination
SE01 Entry into force of request for substantive examination
GR01 Patent grant
GR01 Patent grant