CN117399056A - Denitration catalyst and preparation method thereof - Google Patents

Denitration catalyst and preparation method thereof Download PDF

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Publication number
CN117399056A
CN117399056A CN202210807293.9A CN202210807293A CN117399056A CN 117399056 A CN117399056 A CN 117399056A CN 202210807293 A CN202210807293 A CN 202210807293A CN 117399056 A CN117399056 A CN 117399056A
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molecular sieve
precursor
mass
denitration catalyst
ion exchange
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刘军强
刘光利
贾媛媛
张鹏
巫树锋
唐中华
刘兴誉
蒲欣
杨岳
王军
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Petrochina Co Ltd
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Petrochina Co Ltd
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    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
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    • B01J29/00—Catalysts comprising molecular sieves
    • B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
    • B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • B01J29/40—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively
    • B01J29/48—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of the pentasil type, e.g. types ZSM-5, ZSM-8 or ZSM-11, as exemplified by patent documents US3702886, GB1334243 and US3709979, respectively containing arsenic, antimony, bismuth, vanadium, niobium tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
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    • 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
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    • B01J29/00—Catalysts comprising molecular sieves
    • B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
    • B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • B01J29/70—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65
    • B01J29/78—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65 containing arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J29/7815—Zeolite Beta
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    • B01J29/00—Catalysts comprising molecular sieves
    • B01J29/04—Catalysts comprising molecular sieves having base-exchange properties, e.g. crystalline zeolites
    • B01J29/06—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof
    • B01J29/70—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65
    • B01J29/78—Crystalline aluminosilicate zeolites; Isomorphous compounds thereof of types characterised by their specific structure not provided for in groups B01J29/08 - B01J29/65 containing arsenic, antimony, bismuth, vanadium, niobium, tantalum, polonium, chromium, molybdenum, tungsten, manganese, technetium or rhenium
    • B01J29/783—CHA-type, e.g. Chabazite, LZ-218
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    • 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
    • B01J37/06—Washing
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/30—Ion-exchange
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    • B01J37/00—Processes, in general, for preparing catalysts; Processes, in general, for activation of catalysts
    • B01J37/34—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation
    • B01J37/341—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation
    • B01J37/343—Irradiation by, or application of, electric, magnetic or wave energy, e.g. ultrasonic waves ; Ionic sputtering; Flame or plasma spraying; Particle radiation making use of electric or magnetic fields, wave energy or particle radiation of ultrasonic wave energy
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    • B01J2229/10—After treatment, characterised by the effect to be obtained
    • B01J2229/18—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself
    • B01J2229/186—After treatment, characterised by the effect to be obtained to introduce other elements into or onto the molecular sieve itself not in framework positions

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Abstract

The invention provides a denitration catalyst and a preparation method thereof, wherein the denitration catalyst has a core-shell structure, the core comprises a molecular sieve, a metal component is loaded on the molecular sieve, the shell layer is metal oxide, and the metal oxide at least comprises ZrO 2 The shell coats the core, and the metal oxide is bonded with the molecular sieve through chemical bonding. Zeol of the inventionite@ZrO 2 After aging treatment in a water vapor environment, the catalyst shows good denitration activity and water resistance and sulfur resistance.

Description

Denitration catalyst and preparation method thereof
Technical Field
The invention relates to the technical field of new inorganic materials, in particular to a denitration catalyst and a preparation method thereof.
Background
Nitrogen Oxides (NO) x ) Is one of the main atmospheric pollutants, and the emission requirements are increasingly strict. Among the numerous flue gas denitration technologies, the selective catalytic reduction (Selective Catalytic Reduction, SCR) is still the international mainstream technology, NO x The removal rate can reach more than 80 percent. The denitration catalyst is the core of SCR technology, a series of denitration catalysts of different boiler types and the like are developed in the last 80 th century in developed countries, a series of researches are also carried out by a plurality of scientific research units and enterprises in China aiming at the conditions of fuel boiler smoke and refined smoke in China, and some denitration catalysts are developed.
The molecular sieve has high specific surface area, rich topological structure and wide temperature window, is a research hot spot of the current SCR denitration catalyst, but the hydrothermal stability and the sulfur resistance of the molecular sieve denitration catalyst are still to be improved, the water resistance and the sulfur resistance of the molecular sieve are mainly improved by coating a functional layer outside the molecular sieve, but the existing coating technology cannot enable the coating layer to be firmly coated on the surface of the core molecular sieve, the coating layer is easy to fall off in long-time operation, the water resistance and the sulfur resistance of the catalyst are affected, and the denitration rate is further reduced.
CN201710423091.3 proposes a Fe-ZSM-5@Ce/meso-SiO 2 Denitration catalyst and preparation method thereof, firstly, fe-ZSM-5 surface is modified, and then SiO is coated on the catalyst surface 2 The Ce element is loaded on the catalyst by an impregnation method to obtain the Fe-ZSM-5@Ce/meso-SiO with a core-shell structure 2 The denitration performance, water resistance and sulfur resistance of the catalyst at the low temperature section are improved; however, the catalyst has no special treatment between the core and the shell, and the performance of the catalyst is reduced due to the shell falling off in long-term operation.
CN201810881492.8 proposes a denitration catalyst with a core-shell structure and a preparation method thereof, wherein a Cu-Ce-La-SSZ-13 molecular sieve is subjected to surface treatment, then a seed crystal precursor is adsorbed, and then the seed crystal precursor is put into a shell layer silicate-1 precursor synthesis solution to synthesize the Cu-Ce-La-SSZ-13@silicate-1 catalyst with the core-shell structure.
Thus, there is still a need in the art for further investigation of denitration catalysts.
Disclosure of Invention
The invention mainly aims to provide a denitration catalyst and a preparation method thereof, which are used for solving the problems that in the prior art, the combination of a core-shell structure catalyst core and a coating layer is not firm, the coating layer is easy to fall off in long-time operation, the water resistance and sulfur resistance of the catalyst are reduced, and the denitration performance of the catalyst is influenced.
In order to achieve the aim, the invention provides a denitration catalyst which has a core-shell structure, wherein the core comprises a molecular sieve, a metal component is loaded on the molecular sieve, the shell layer is metal oxide, and the metal oxide at least comprises ZrO 2 The shell coats the core, and the metal oxide is bonded with the molecular sieve through chemical bonding.
The denitration catalyst provided by the invention is characterized in that the molecular sieve is one or more of an SSZ-13 type molecular sieve, an SAPO-34 type molecular sieve, an LTA type molecular sieve, a ZSM-5 type molecular sieve, a BETA type molecular sieve, an MCM-41 type molecular sieve, a Y type molecular sieve, an S-1 type molecular sieve and a TS-1 type molecular sieve; the metal component is one or more of Cu, fe, mn and Ce, and the metal component accounts for 1-20% of the total mass of the core.
The denitration catalyst of the invention, wherein the metal oxide further comprises V 2 O 5 And/or MoO 2 The method comprises the steps of carrying out a first treatment on the surface of the The total mass of the shell layer accounts for 20% -80% of the total mass of the core.
The denitration catalyst of the invention, wherein V 2 O 5 Occupying ZrO in the shell layer 2 2 to 12 percent of MoO 2 Occupying ZrO in the shell layer 2 1 to 20 percent of the mass.
In order to achieve the above purpose, the invention also provides a preparation method of the denitration catalyst, which comprises the following steps:
step 1, carrying out ammonium ion exchange on a molecular sieve, and then carrying out ion exchange on the molecular sieve and a metal source;
step 2, mixing the molecular sieve obtained in the step 1 with an alkali solution, and performing surface treatment under the action of ultrasonic waves to expose binding sites on the surface of the molecular sieve;
and step 3, adding the shell metal precursor into the mixture obtained in the step 2, and adjusting the pH value to enable the shell metal precursor to react with the binding sites on the molecular sieve in a binding way, so as to obtain the denitration catalyst.
The invention relates to a preparation method of a denitration catalyst, wherein the ammonium ion exchange of a molecular sieve is carried out by adding the molecular sieve into an ammonium salt solution for exchange, and the ammonium salt is NH 4 Cl、NH 4 NO 3 、 (NH 4 ) 2 SO 4 The mass concentration of the ammonium salt solution is 5-40%, and the solid-liquid mass ratio of the molecular sieve to the ammonium salt solution is 1:2-15.
The invention relates to a preparation method of a denitration catalyst, wherein in the step 1, the step of carrying out ion exchange with a metal source is as follows: mixing a molecular sieve obtained by ammonium ion exchange with a metal source solution, and performing ion exchange; the metal source is one or more of copper-containing salt, ferric salt, manganese-containing salt and cerium-containing salt, and further is one or more of acetate, chloride and nitrate of Cu, fe, mn or Ce; the mass concentration of the metal source solution is 0.5-10%, and the solid-liquid mass ratio of the molecular sieve to the metal source solution after the ammonium ion exchange is 1:2-10.
The invention relates to a preparation method of a denitration catalyst, wherein the step 2 is as follows: mixing the molecular sieve obtained in the step 1 with an organic solvent, and then mixing with an alkali solution; the organic solvent is one or more of ethanol, glycol and acetonitrile, the mass concentration of the alkali solution is 0.5-2%, and the alkali is one of NaOH and KOH.
The invention relates to a preparation method of a denitration catalyst, wherein a pore-forming agent is also added in the step 3, and the pore-forming agent is one or two of cetyl trimethyl ammonium bromide and polyvinylpyrrolidone.
The invention relates to a preparation method of a denitration catalyst, wherein the shell metal precursor comprises a zirconium precursor, and the zirconium precursor is one or more of zirconium chloride, zirconium nitrate and zirconium sulfate.
The invention relates to a preparation method of a denitration catalyst, wherein the shell metal precursor further comprises a molybdenum precursor and/or a vanadium precursor, wherein the molybdenum precursor is molybdic acid and ammonium meta-molybdate, and the vanadium precursor is vanadate and ammonium meta-vanadate; the zirconium precursor is ZrO 2 The vanadium precursor is expressed in terms of V by mass 2 O 5 Mass of the molybdenum precursor in MoO 3 The mass ratio of the total mass of the zirconium precursor, the vanadium precursor and the molybdenum precursor to the molecular sieve obtained in the step 1 is 1-4:5, and the mass ratio of the zirconium precursor, the vanadium precursor and the molybdenum precursor is 100 (2-12) to 1-20.
The preparation method of the denitration catalyst provided by the invention comprises the steps of adding the pore-forming agent and the zirconium precursor in a mass ratio of 0.2-5:10.
The invention has the beneficial effects that:
(1) After the molecular sieve is subjected to surface alkali treatment before the catalyst is coated, metal ions (Cu, fe, mn or Ce) on the surface of the molecular sieve can be partially combined with hydroxyl ions, so that sites capable of being combined with zirconium atoms are exposed.
(2) The invention introduces V in the shell layer 2 O 5 So that the oxidation of NO to NO can be established in the shell layer 2 Is NO on the core molecular sieve 2 With NH 3 、O 2 The rapid denitration reaction occurs, so that the denitration performance after coating the shell layer is improved to some extent.
(3) zeolite@ZrO according to the invention 2 After aging treatment in a water vapor environment, the catalyst still shows good denitration activity and water resistance and sulfur resistance.
Detailed Description
The following embodiments are provided by carrying out the embodiments of the present invention on the premise of the embodiments of the present invention, and the detailed implementation process is given, but the scope of the present invention is not limited to the following embodiments, and the following embodiments do not specify specific conditions, structures or experimental methods, and generally follow conventional conditions.
The invention provides a denitration catalyst, which has a core-shell structure, wherein the core comprises a molecular sieve, a metal component is loaded on the molecular sieve, the shell layer is metal oxide, and the metal oxide at least comprises ZrO 2 The shell coats the core, and the metal oxide is bonded with the molecular sieve through chemical bonding.
According to the catalyst disclosed by the invention, the metal oxide serving as the shell layer and the molecular sieve serving as the core are bonded through chemical bonds, so that the bonding force between the coating layer and the core can be greatly improved, and the problem that the shell layer falls off even if the catalyst is operated for a long time is solved. Therefore, the catalyst of the invention can run for a long time on the basis of keeping high activity, and has longer service life.
zeolite@ZrO according to the invention 2 After aging treatment in a water vapor environment, the catalyst still shows good denitration activity and water resistance and sulfur resistance.
In one embodiment, the molecular sieve of the present invention is one or more of SSZ-13 type molecular sieve, SAPO-34 type molecular sieve, LTA type molecular sieve, ZSM-5 type molecular sieve, BETA type molecular sieve, MCM-41 type molecular sieve, Y type molecular sieve, S-1 type molecular sieve, and TS-1 type molecular sieve; the molecular sieve is also loaded with metal components such as copper, iron, manganese, cerium.
Wherein the shell layer is metal oxide, and the metal oxide at least comprises ZrO 2 . In one embodiment, the metal oxide further comprises V 2 O 5 And/or MoO 2 . Specifically, the metal in the metal oxide is bonded to aluminum or silicon on the molecular sieve through oxygen.
In one embodiment, the denitration catalyst of the present invention is denoted as zeolite@ZrO 2 The metal component accounts for 1-20% of the total mass of the core; the total mass of the shell layer accounts for 20% -80% of the total mass of the core; v (V) 2 O 5 ZrO in the shell layer 2 2 to 12 percent of MoO 2 ZrO in the shell layer 2 1 to 20 percent of the mass.
The catalyst of the invention is prepared by introducing V into a shell layer 2 O 5 Can build NO oxidation to NO in the shell 2 Is further NO on the core molecular sieve 2 With NH 3 、O 2 The rapid denitration reaction occurs, so that the denitration catalyst performance after coating the shell layer is improved.
In an embodiment, the invention also provides a preparation method of the denitration catalyst, which comprises the following steps:
step 1, carrying out ammonium ion exchange on a molecular sieve, and then carrying out ion exchange on the molecular sieve and a metal source;
step 2, mixing the molecular sieve obtained in the step 1 with an alkali solution, and performing surface treatment under the action of ultrasonic waves to expose binding sites on the surface of the molecular sieve;
and step 3, adding the shell metal precursor into the mixture obtained in the step 2, and adjusting the pH value to enable the shell metal precursor to react with the binding sites on the molecular sieve in a binding way, so as to obtain the denitration catalyst.
Before the shell is coated by the catalyst, the surface of the molecular sieve is treated to expose bonding sites, and when the catalyst is coated, metal atoms (zirconium atoms) at the bonding position of the shell and the core are bonded with the core molecular sieve and metal oxides of the shell, and the core and the shell are connected through chemical bonds, so that the bonding force between the coating layer and the core is greatly improved, the shell is not separated after the catalyst is operated for a long time, and the catalytic performance is not reduced after the catalyst is operated for a long time.
The type of molecular sieve is not particularly limited in the present invention, and preferred molecular sieves are listed in detail above and will not be described in detail herein. The present invention is not particularly limited in the ammonium ion exchange step of the molecular sieve, for example, the molecular sieve is added to an ammonium salt solution for exchange, more for example, the exchange step is as follows: adding H-zeolite into ammonium salt solution, uniformly mixing, performing ion exchange under high-speed magnetic stirring, washing the mixture with deionized water to neutrality, and drying to obtain NH 4 + Zeolite carrier material.
Wherein the ammonium salt may be NH 4 Cl、NH 4 NO 3 、(NH 4 ) 2 SO 4 The mass concentration of the ammonium salt solution is 5-40%, preferably 10-30%, and the solid-liquid mass ratio of the H-zeolite to the ammonium salt solution is 1:2-15, preferably 1:6-12.
In one embodiment, the temperature of the ammonium ion exchange is 20 to 90 ℃, preferably 60 to 90 ℃, and the ion exchange time is 1 to 10 hours, preferably 3 to 6 hours. Drying at 60-140 ℃ for 4-20 h after ammonium ion exchange, preferably: drying at 80-110 deg.c for 8-15 hr.
And ion exchanging the molecular sieve subjected to the ammonium ion exchange with a metal source. The invention feeds molecular sieve and metal source The manner of ion exchange is not particularly limited, and for example, a metal source solution is mixed with a molecular sieve after ammonium ion exchange to perform ion exchange; more specifically, the method comprises the following steps: NH obtained by exchanging a metal source solution with ammonium ions 4 + The zeolite is uniformly mixed, ion exchange is carried out under high-speed magnetic stirring, and then the mixture is washed clean by deionized water, dried and roasted, thus obtaining the molecular sieve after ion exchange.
In one embodiment, the metal source is one or more of copper-containing salt, iron-containing salt, manganese-containing salt and cerium-containing salt, and further, is a soluble salt of a metal, such as one or more of copper, iron, manganese, cerium acetate, chloride and nitrate. The mass concentration of the metal source solution is 0.5-10%, preferably 1-4%, and NH 4 + The solid-liquid mass ratio of the zeolite to the metal source solution is 1:2-10, preferably 1:3-6.
In one embodiment, the temperature of ion exchange of the molecular sieve with the metal source is 20 to 90 ℃, preferably 50 to 70 ℃, and the ion exchange time is 1 to 10 hours, preferably 1.5 to 3 hours. Drying at 60-140 ℃ for 4-20 h after ion exchange, preferably: drying at 80-110 deg.c for 8-15 hr; the roasting conditions are as follows: roasting for 1-10 h at 300-700 ℃, preferably: roasting at 500-600 deg.c to 2-6 h deg.c.
The step 2 is as follows: mixing the molecular sieve obtained in the step 1 with an alkali solution, and carrying out surface treatment under the action of ultrasonic waves to expose binding sites on the surface of the molecular sieve.
In one embodiment, the preparation method of the denitration catalyst further comprises mixing the molecular sieve obtained in the step 1 with an organic solvent, and then mixing the mixture with an alkali solution for surface treatment.
Specifically, adding the molecular sieve obtained in the step 1 into an organic solvent for washing for 2-4 times; adding an organic solvent into the washed molecular sieve to obtain a suspension, adding a proper amount of alkali solution into the suspension, and carrying out surface treatment on the molecular sieve under the action of ultrasonic waves to expose binding sites on the surface of the molecular sieve.
The organic solvent is not particularly limited, and the organic solvent for washing and the organic solvent mixed with the molecular sieve can be the same or different and are selected from one or more of ethanol, glycol and acetonitrile; preferably ethanol/acetonitrile mixed solution, and the volume ratio of ethanol to acetonitrile is preferably 1-3:1.
In one embodiment, the mass concentration of the alkali solution is 0.5-2%, the alkali can be one of NaOH and KOH, and the volume ratio of the suspension to the alkali solution is 4-10:1.
The step 3 is as follows: and (3) adding the shell metal precursor into the mixture obtained in the step (2), and adjusting the pH value to enable the shell metal precursor to react with the binding site on the molecular sieve in a binding way, so as to obtain the denitration catalyst.
In detail, the step 3 is as follows: dissolving a shell metal precursor into an organic solvent, homogenizing to obtain a mixture, adding the homogenized mixture into the mixture in the step 2, heating to combine the shell metal element with a binding site, adjusting the pH value to react, filtering and collecting a product after the reaction is finished, washing, drying and roasting, and removing organic substances in a shell.
The shell metal precursor of the present invention comprises a zirconium precursor, and in one embodiment, a molybdenum precursor and/or a vanadium precursor. Wherein, zirconium precursor, molybdenum precursor, vanadium precursor and the like are all common substances for preparing denitration catalyst in the prior art, and the dosage is also selected to be proper according to the process characteristics, and the invention is not particularly limited. As a preferable scheme, the zirconium precursor is one or more of zirconium chloride, zirconium nitrate and zirconium sulfate, the molybdenum precursor is molybdic acid and ammonium meta-molybdate, and the vanadium precursor is vanadate and ammonium meta-vanadate. Zirconium precursor, zrO 2 Mass of vanadium precursor is V 2 O 5 Mass, molybdenum precursor in MoO 3 The mass ratio of the total mass of the zirconium precursor, the vanadium precursor and the molybdenum precursor to the molecular sieve obtained in the step 1 is 1-4:5, and the mass ratio of the zirconium precursor, the vanadium precursor and the molybdenum precursor is 100 (2-12), 1-20, preferably 100 (2-6) and 5-15.
The organic solvent for dissolving the shell metal precursor can be one or more of ethanol, glycol and acetonitrile, preferably ethanol/acetonitrile mixed solution, and the volume ratio of the ethanol to the acetonitrile is preferably 1-3:1.
In one embodiment, the invention adjusts the pH value to 8-12 to react, and the drying condition is as follows: drying at 40-90 deg.c for 1-12 hr, preferably: drying at 60-80 deg.c for 3-7 hr; the roasting conditions are as follows: roasting for 1-10 h at 300-700 ℃, preferably: roasting for 2-6 h at 500-600 ℃.
In one embodiment, a pore-forming agent, such as one or two of cetyl trimethyl ammonium bromide and polyvinylpyrrolidone, is added when the shell metal precursor is dissolved in the organic solvent, wherein the mass ratio of the pore-forming agent to the zirconium precursor is 0.2-5:10, preferably 0.5-2:10.
Therefore, the invention provides a preparation method for preparing the denitration catalyst, and the catalyst obtained by the preparation method provided by the invention has the advantages that the specific surface treatment step of the molecular sieve is added, so that the surface of the catalyst can be exposed to binding sites, the binding capacity of the core molecular sieve and the shell layer is further enhanced, the separation of the shell layer and the core layer during the use of the catalyst is prevented, and the stability of the catalyst is enhanced.
The technical scheme of the invention will be further described in detail through specific examples. The "%" described in examples and comparative examples refers to mass% unless otherwise specified.
Preparation of catalyst sample: crushing the prepared fresh catalyst, sieving to obtain powder with 20-40 meshes, and aging for 24 hours at 850 ℃ in a 15% water vapor environment to be evaluated.
NO x Conversion evaluation conditions: airspeed 20000h -1 Reaction temperature is 350 ℃, and inlet air NO x 1000mg/Nm 3 、SO 2 300mg/Nm 3 The ammonia nitrogen ratio is 1, and the water content is 10wt%.
NO x 、SO 2 The concentration measuring method comprises the following steps: a smoke continuous on-line analyzer, siemens ultra mat23.
Example 1:
(1) 40g H-SSZ-13 molecular sieves were added to 480g of NH at 20% mass concentration 4 Mixing with Cl solutionMixing uniformly, performing ion exchange under high-speed magnetic stirring at 60deg.C for 6 hr, washing the mixture with deionized water to neutrality, and drying at 105deg.C for 11 hr to obtain NH 4 + -SSZ-13 carrier material; then 32g NH 4 + Adding SSZ-13 into 112 g copper acetate solution with the mass concentration of 1%, uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, wherein the ion exchange temperature is 65 ℃ for 1.5 hours, washing the mixture with deionized water to be neutral, drying at 110 ℃ for 8 hours, and roasting at 520 ℃ for 2 hours, thereby obtaining the Cu-SSZ-13 molecular sieve prepared by the liquid phase ion exchange method.
(2) Weighing 25.6g of the Cu-SSZ-13 molecular sieve powder prepared in the step (1), adding the powder into 150mL of ethanol solution to form suspension, magnetically stirring for 30min, adding 44mL of NaOH solution with mass concentration of 1%, and performing ultrasonic treatment; 14.35g of zirconium chloride (as ZrO 2 Mass), 0.72g of molybdic acid (in MoO 3 Mass), 0.29g of vanadate (in V 2 O 5 Mass), 2.87g of cetyl trimethyl ammonium bromide was added to 150mL of ethanol solution, which was then added to the above suspension, and the pH was adjusted to 11 to react for 1 hour; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 60℃for 5 hours and calcined in a muffle furnace at 600℃for 5 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Comparative example 1:
(1) 40g H-SSZ-13 is added to 480g of NH with a mass concentration of 20% 4 Mixing with Cl solution, ion exchanging under high-speed magnetic stirring at 60deg.C for 6 hr, washing with deionized water to neutrality, and drying at 105deg.C for 11 hr to obtain NH 4 + -SSZ-13 carrier material; then 32g NH 4 + SSZ-13 is added into 112g of 1% copper acetate solution, and mixed uniformly, ion exchange is carried out under high-speed magnetic stirring, the ion exchange temperature is 65 ℃ for 1.5h, then the mixture is washed to be neutral by deionized water, dried for 8h at 110 ℃, and then baked at 520 DEG C And (3) calcining for 2 hours, thereby obtaining the Cu-SSZ-13 molecular sieve prepared by the liquid phase ion exchange method.
(2) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Example 2:
(1) 80g H-SSZ-13 is added to 480g of ammonium salt (NH) 4 Cl and (NH) 4 ) 2 SO 4 The mass ratio is 1:1), and the mixture is evenly mixed, ion exchange is carried out under high-speed magnetic stirring, the ion exchange temperature is 75 ℃, the time is 4.5h, then the mixture is washed to be neutral by deionized water, and the mixture is dried for 15h at 90 ℃ to obtain NH 4 + -SSZ-13 carrier material; 64 g of NH 4 + SSZ-13 is added into 384g of copper chloride solution with the mass concentration of 3 percent, and is uniformly mixed, ion exchange is carried out under high-speed magnetic stirring, the ion exchange temperature is 70 ℃ and the time is 3 hours, then the mixture is washed to be neutral by deionized water, dried for 14 hours at 95 ℃, and then baked for 6 hours at 600 ℃, thus obtaining the Cu-SSZ-13 molecular sieve prepared by a liquid phase ion exchange method.
(2) Weighing 51g of the Cu-SSZ-13 molecular sieve powder prepared in the step (1), adding the Cu-SSZ-13 molecular sieve powder into 150mL of ethanol/acetonitrile (the volume ratio of ethanol to acetonitrile is 1:1) mixed solution to form suspension, magnetically stirring for 30min, adding 40mL of KOH solution with the mass concentration of 0.5%, and carrying out ultrasonic treatment; 9.19g of zirconium sulfate (as ZrO 2 Mass), 0.46g of ammonium meta-molybdate (in MoO 3 Mass), 0.55g of ammonium metavanadate (in V 2 O 5 Mass), 0.92g of cetyl trimethyl ammonium bromide and 0.46g of polyvinylpyrrolidone are added into 150mL of ethanol/acetonitrile (the volume ratio of ethanol to acetonitrile is 1:1) mixed solution, and then added into the suspension, and the pH value is adjusted to 8 to react for 1h; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 80℃for 3 hours and calcined in a muffle furnace at 540℃for 3 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Comparative example 2:
(1) 80-g H-SSZ-13 is added into 480g of ammonium salt with mass concentration of 10%NH4Cl and (NH) 4 ) 2 SO 4 The mass ratio is 1:1), and the mixture is evenly mixed, ion exchange is carried out under high-speed magnetic stirring, the ion exchange temperature is 75 ℃, the time is 4.5h, then the mixture is washed to be neutral by deionized water, and the mixture is dried for 15h at 90 ℃ to obtain NH 4 + -SSZ-13 carrier material; 64g of NH 4 + SSZ-13 is added into 384g of copper chloride solution with the mass concentration of 3 percent, and is uniformly mixed, ion exchange is carried out under high-speed magnetic stirring, the ion exchange temperature is 70 ℃ and the time is 3 hours, then the mixture is washed to be neutral by deionized water, dried for 14 hours at 95 ℃, and then baked for 6 hours at 600 ℃, thus obtaining the Cu-SSZ-13 molecular sieve prepared by a liquid phase ion exchange method.
(2) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Example 3:
(1) 60g H-ZSM-5 was added to 480g of NH with a mass concentration of 25% 4 NO 3 Mixing the above materials, performing ion exchange under high-speed magnetic stirring at 80deg.C for 3 hr, washing the mixture with deionized water to neutrality, and drying at 85deg.C for 8 hr to obtain NH 4 + -a ZSM-5 support material; 48g NH 4 + Adding ZSM-5 into 240g of a copper source solution with the mass concentration of 4% (the mass ratio of copper chloride to copper nitrate is 1:2), uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, washing the mixture to be neutral by deionized water at the ion exchange temperature of 50 ℃ for 2.5h, drying at 80 ℃ for 12h, and roasting at 500 ℃ for 4 h to obtain the Cu-ZSM-5 molecular sieve prepared by the liquid-phase ion exchange method.
(2) Weighing 38.4g of the Cu-ZSM-5 molecular sieve powder prepared in the step (1), adding the Cu-ZSM-5 molecular sieve powder into 150mL of acetonitrile solution to form suspension, magnetically stirring for 30min, adding 24mL of NaOH solution with mass concentration of 2%, and performing ultrasonic treatment; 13.47g of zirconium sulfate (as ZrO 2 Mass), 1.35g of molybdic acid (in MoO 3 Mass), 0.54g of ammonium metavanadate (in V 2 O 5 Mass), 0.67. 0.67 g polyvinylpyrrolidone to 150mLAcetonitrile solution, then adding the mixture into the suspension, and adjusting the pH value to 10 to react for 1h; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 65℃for 7 hours and calcined in a muffle furnace at 580℃for 6 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Comparative example 3:
(1) 60g H-ZSM-5 was added to 480g of NH with a mass concentration of 25% 4 NO 3 Mixing the above materials, performing ion exchange under high-speed magnetic stirring at 80deg.C for 3 hr, washing the mixture with deionized water to neutrality, and drying at 85deg.C for 8 hr to obtain NH 4 + -a ZSM-5 support material; 48g NH 4 + Adding ZSM-5 into 240g of a copper source solution with the mass concentration of 4% (the mass ratio of copper chloride to copper nitrate is 1:2), uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, washing the mixture to be neutral by deionized water at the ion exchange temperature of 50 ℃ for 2.5h, drying at 80 ℃ for 12h, and roasting at 500 ℃ for 4 h to obtain the Cu-ZSM-5 molecular sieve prepared by the liquid-phase ion exchange method.
(2) Weighing 38.4g of the Cu-ZSM-5 molecular sieve powder prepared in the step (1), adding the Cu-ZSM-5 molecular sieve powder into 150mL of acetonitrile solution to form suspension, and magnetically stirring for 30min; 13.47g of zirconium sulfate (as ZrO 2 Mass), 1.35g of molybdic acid (in MoO 3 Mass), 0.54g of ammonium metavanadate (in V 2 O 5 Mass), 0.67g of polyvinylpyrrolidone was added to 150mL of acetonitrile solution, which was then added to the above suspension, and the PH was adjusted to 10 to react for 1 hour; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 65℃for 7 hours and calcined in a muffle furnace at 580℃for 6 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Example 4:
(1) 48g H-ZSM-5 was added to 480g of 15% by mass ammonium salt (NH 4 NO 3 、(NH 4 ) 2 SO 4 The mass ratio is 1:3) of the solution and is evenly mixedIon exchange is carried out under high-speed magnetic stirring, the ion exchange temperature is 65 ℃ and the time is 5.5h, then the mixture is washed to be neutral by deionized water, and dried for 10h at 110 ℃ to obtain NH 4 + -a ZSM-5 support material; 38.4g NH was then added 4 + Adding 173g of copper source (the mass ratio of copper acetate to copper nitrate is 5:1) solution with the mass concentration of 2%, uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, wherein the ion exchange temperature is 60 ℃ for 2 hours, washing the mixture with deionized water to be neutral, drying at 85 ℃ for 15 hours, and roasting at 540 ℃ for 3 hours, thereby obtaining the Cu-ZSM-5 molecular sieve prepared by the liquid phase ion exchange method.
(2) Weighing 30.7g of the Cu-ZSM-5 molecular sieve powder prepared in the step (1), adding the Cu-ZSM-5 molecular sieve powder into 150mL of ethanol/acetonitrile (the volume ratio of ethanol to acetonitrile is 3:1) mixed solution to form suspension, magnetically stirring for 30min, adding 20mL of KOH solution with the mass concentration of 1.5%, and carrying out ultrasonic treatment; 15.3g of a zirconium source (zirconium sulfate, zirconium nitrate 7.65g, respectively, 7.65g, zrO 2 Mass), 2.29g of molybdic acid (in MoO 3 Mass), 0.92g of vanadate (in V 2 O 5 Mass), 0.51g of cetyl trimethyl ammonium bromide and 1.02g of polyvinylpyrrolidone are added into 150mL of ethanol/acetonitrile (the volume ratio of ethanol to acetonitrile is 3:1) mixed solution, and then added into the suspension, and the pH value is adjusted to 12 to react for 1h; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 70℃for 4 hours, and calcined in a muffle furnace at 500℃for 4 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Example 5:
(1) Adding 68g H-BETA into 480g of 30% ammonium salt solution (NH) 4 Cl、NH 4 NO 3 、(NH 4 ) 2 SO 4 In the mass ratio of 4:1:2), and uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, wherein the ion exchange temperature is 90 ℃, the time is 4 hours, then washing the mixture to be neutral by deionized water, and drying at 100 ℃ for 12 hours to obtain NH 4 + -a BETA carrier material; then will be 54.4g NH 4 + Adding BETA into 218g copper nitrate solution with mass concentration of 1%, mixing, performing ion exchange under high-speed magnetic stirring at 55deg.C for 1.5 hr, washing the mixture with deionized water to neutrality, drying at 105deg.C for 9 h, and calcining at 580 deg.C for 5 hr to obtain Cu-BETA molecular sieve prepared by liquid phase ion exchange method.
(2) Weighing 43.5g of the Cu-BETA molecular sieve powder obtained in the step (1), adding into 150mL of glycol solution to form suspension, magnetically stirring for 30min, adding 32mL of KOH solution with mass concentration of 0.5%, and performing ultrasonic treatment; 7.44g of zirconium sulfate (as ZrO 2 Mass), 1.12g of ammonium meta-molybdate (in MoO 3 Mass), 0.15g of vanadate (in V 2 O 5 Mass), 1.49. 1.49 g hexadecyl trimethyl ammonium bromide is added into 150mL of glycol solution, then added into the suspension, and the PH value is adjusted to 10 to react for 1h; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 75℃for 6 hours and calcined in a muffle furnace at 520℃for 2 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Comparative example 5:
(1) Adding 68g H-BETA into 480g of 30% ammonium salt solution (NH) 4 Cl、NH 4 NO 3 、(NH 4 ) 2 SO 4 In the mass ratio of 4:1:2), and uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, wherein the ion exchange temperature is 90 ℃, the time is 4 hours, then washing the mixture to be neutral by deionized water, and drying at 100 ℃ for 12 hours to obtain NH 4 + -a BETA carrier material; then 54.4g NH 4 + Adding BETA into 218g copper nitrate solution with mass concentration of 1%, mixing, performing ion exchange under high-speed magnetic stirring at 55deg.C for 1.5 hr, washing the above mixture with deionized water to neutrality, drying at 105deg.C for 9 hr, and calcining at 580 deg.C for 5 hr to obtain Cu-BETA molecular sieve prepared by liquid phase ion exchange method.
(2) Weighing 43.5g of the product obtained in the step (1)Adding Cu-BETA molecular sieve powder into 150mL glycol solution to form suspension, and magnetically stirring for 30min; 7.44g of zirconium sulfate (as ZrO 2 Mass), 1.12g of ammonium meta-molybdate (in MoO 3 Mass), 0.15g of vanadate (in V 2 O 5 Mass), 1.49g of cetyl trimethyl ammonium bromide was added to 150mL of ethylene glycol solution, which was then added to the above suspension, and the pH was adjusted to 10 to allow it to react for 1 hour; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 75℃for 6 hours and calcined in a muffle furnace at 520℃for 2 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Example 6:
(1) Adding 53g H-BETA into 480g (NH) with mass concentration of 30% 4 ) 2 SO 4 Mixing uniformly, performing ion exchange under high-speed magnetic stirring at 85deg.C for 3.5 hr, washing the mixture with deionized water to neutrality, and drying at 80deg.C for 9 hr to obtain NH 4 + -a BETA carrier material; 42.4g NH was then added 4 + Adding BETA into 127g copper source (copper acetate, copper chloride and copper nitrate with mass ratio of 1:4:3) solution, mixing, performing ion exchange under high-speed magnetic stirring at 70deg.C for 2 hr, washing the mixture with deionized water to neutrality, drying at 90deg.C for 10 hr, and calcining at 500deg.C for 4.5 hr to obtain Cu-BETA molecular sieve prepared by liquid phase ion exchange method.
(2) Weighing 33.9g of the Cu-BETA molecular sieve powder obtained in the step (1), adding into 150mL of mixed solution of glycol/acetonitrile (the volume ratio of glycol/acetonitrile is 1:1) to form a suspension, magnetically stirring for 30min, adding 18.4mL of 1% NaOH solution by mass concentration, and performing ultrasonic treatment; 23.6g of a zirconium source (wherein zirconium chloride, zirconium sulfate and zirconium nitrate are 2.62g, 13.11g and 7.87. 7.87 g, respectively, as ZrO 2 Mass), 2.83g of ammonium meta-molybdate (in MoO 3 Mass), 0.71g of metavanadate (in V 2 O 5 Mass), 2.36g of polyvinylpyrrolidone was added to 150mL of a mixed solution of ethylene glycol/acetonitrile (ethylene glycol/acetonitrile volume 1:1)Then adding the mixture into the suspension, and adjusting the PH value to react for 1h; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 75℃for 4 hours and calcined in a muffle furnace at 560℃for 5 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Example 7:
(1) 60g H-ZSM-5 was added to 480g of NH with a mass concentration of 25% 4 NO 3 Mixing the above materials, performing ion exchange under high-speed magnetic stirring at 80deg.C for 3 hr, washing the mixture with deionized water to neutrality, and drying at 85deg.C for 8 hr to obtain NH 4 + -a ZSM-5 support material; 48g NH 4 + Adding ZSM-5 into 240g of solution of iron source with mass concentration of 4% (the mass ratio of ferric chloride to ferric nitrate is 1:2), uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, washing the mixture to be neutral by deionized water at the ion exchange temperature of 50 ℃ for 2.5h, drying at 80 ℃ for 12h, and roasting at 500 ℃ for 4h to obtain the Fe-ZSM-5 molecular sieve prepared by the liquid phase ion exchange method.
(2) Weighing 38.4g of Fe-ZSM-5 molecular sieve powder prepared in the step (1), adding the Fe-ZSM-5 molecular sieve powder into 150mL of acetonitrile solution to form suspension, magnetically stirring for 30min, adding 24mL of NaOH solution with mass concentration of 2%, and performing ultrasonic treatment; 13.47g of zirconium sulfate (as ZrO 2 Mass), 1.35g of molybdic acid (in MoO 3 Mass), 0.54g of ammonium metavanadate (in V 2 O 5 Mass), 0.67. 0.67 g polyvinylpyrrolidone was added to 150mL of acetonitrile solution, which was then added to the above suspension, and the PH was adjusted to 10 to react for 1 hour; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 65℃for 7 hours and calcined in a muffle furnace at 580℃for 6 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Comparative example 7:
(1) 60g H-ZSM-5 was added to 480g of NH with a mass concentration of 25% 4 NO 3 The mixture is evenly mixed in the solution, and the height is highIon exchange is carried out under rapid magnetic stirring, the ion exchange temperature is 80 ℃ and the time is 3 hours, then the mixture is washed to be neutral by deionized water, and is dried for 8 hours at 85 ℃ to obtain NH 4 + -a ZSM-5 support material; 48g NH 4 + Adding ZSM-5 into 240g of solution of iron source with mass concentration of 4% (the mass ratio of ferric chloride to ferric nitrate is 1:2), uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, washing the mixture to be neutral by deionized water at the ion exchange temperature of 50 ℃ for 2.5h, drying at 80 ℃ for 12h, and roasting at 500 ℃ for 4h to obtain the Fe-ZSM-5 molecular sieve prepared by the liquid phase ion exchange method.
(2) Weighing 38.4g of the Fe-ZSM-5 molecular sieve powder prepared in the step (1), adding the Fe-ZSM-5 molecular sieve powder into 150mL of acetonitrile solution to form suspension, and magnetically stirring for 30min; 13.47g of zirconium sulfate (as ZrO 2 Mass), 1.35g of molybdic acid (in MoO 3 Mass), 0.54g of ammonium metavanadate (in V 2 O 5 Mass), 0.67g of polyvinylpyrrolidone was added to 150mL of acetonitrile solution, which was then added to the above suspension, and the PH was adjusted to 10 to react for 1 hour; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 65℃for 7 hours and calcined in a muffle furnace at 580℃for 6 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Example 8:
(1) Adding 68g H-BETA into 480g of 30% ammonium salt solution (NH) 4 Cl、NH 4 NO 3 、(NH 4 ) 2 SO 4 In the mass ratio of 4:1:2), and uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, wherein the ion exchange temperature is 90 ℃, the time is 4 hours, then washing the mixture to be neutral by deionized water, and drying at 100 ℃ for 12 hours to obtain NH 4 + -a BETA carrier material; then 54.4g NH 4 + Adding BETA into 218g manganese nitrate solution with mass concentration of 1%, mixing, performing ion exchange under high-speed magnetic stirring at 55deg.C for 1.5 hr, washing the mixture with deionized water to neutrality, Drying at 105deg.C for 9 h, and roasting at 580 deg.C for 5 hr to obtain Mn-BETA molecular sieve prepared by liquid phase ion exchange method.
(2) Weighing 43.5g of Mn-BETA molecular sieve powder obtained in step (1), adding into 150mL of glycol solution to form suspension, magnetically stirring for 30min, adding 32mL of KOH solution with mass concentration of 0.5%, and performing ultrasonic treatment; 7.44g of zirconium sulfate (as ZrO 2 Mass), 1.12g of ammonium meta-molybdate (in MoO 3 Mass), 0.15g of vanadate (in V 2 O 5 Mass), 1.49. 1.49 g hexadecyl trimethyl ammonium bromide is added into 150mL of glycol solution, then added into the suspension, and the PH value is adjusted to 10 to react for 1h; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 75℃for 6 hours and calcined in a muffle furnace at 520℃for 2 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Comparative example 8:
(1) Adding 68g H-BETA into 480g of 30% ammonium salt solution (NH) 4 Cl、NH 4 NO 3 、(NH 4 ) 2 SO 4 In the mass ratio of 4:1:2), and uniformly mixing, carrying out ion exchange under high-speed magnetic stirring, wherein the ion exchange temperature is 90 ℃, the time is 4 hours, then washing the mixture to be neutral by deionized water, and drying at 100 ℃ for 12 hours to obtain NH 4 + -a BETA carrier material; then 54.4g NH 4 + Adding BETA into 218g manganese nitrate solution with mass concentration of 1%, mixing, performing ion exchange under high-speed magnetic stirring at 55deg.C for 1.5 hr, washing the above mixture with deionized water to neutrality, drying at 105deg.C for 9 hr, and calcining at 580 deg.C for 5 hr to obtain Mn-BETA molecular sieve prepared by liquid phase ion exchange method.
(2) Weighing 43.5g of Mn-BETA molecular sieve powder obtained in step (1), adding into 150mL of glycol solution to form suspension, and magnetically stirring for 30min; 7.44g of zirconium sulfate (as ZrO 2 Mass), 1.12g of ammonium meta-molybdate (in MoO 3 Mass), 0.15g of vanadate (in V 2 O 5 Mass), 1.49gCetyl trimethyl ammonium bromide is added into 150mL of glycol solution, then added into the suspension, and the PH value is adjusted to 10 to react for 1h; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 75℃for 6 hours and calcined in a muffle furnace at 520℃for 2 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Example 9:
(1) Adding 53g H-BETA into 480g (NH) with mass concentration of 30% 4 ) 2 SO 4 Mixing uniformly, performing ion exchange under high-speed magnetic stirring at 85deg.C for 3.5 hr, washing the mixture with deionized water to neutrality, and drying at 80deg.C for 9 hr to obtain NH 4 + -a BETA carrier material; 42.4g NH was then added 4 + Adding BETA into 127g cerium nitrate solution with mass concentration of 3%, mixing, performing ion exchange under high-speed magnetic stirring at 70deg.C for 2 hr, washing the above mixture with deionized water to neutrality, drying at 90deg.C for 10 hr, and calcining at 500deg.C for 4.5 hr to obtain Ce-BETA molecular sieve prepared by liquid phase ion exchange method.
(2) Weighing 33.9g of Ce-BETA molecular sieve powder obtained in step (1), adding into 150mL of mixed solution of glycol/acetonitrile (volume ratio of glycol/acetonitrile 1:1) to form suspension, magnetically stirring for 30min, adding 18.4mL of 1% NaOH solution by mass concentration, and performing ultrasonic treatment; 23.6g of a zirconium source (wherein zirconium chloride, zirconium sulfate and zirconium nitrate are 2.62g, 13.11g and 7.87. 7.87 g, respectively, as ZrO 2 Mass), 2.83g of ammonium meta-molybdate (in MoO 3 Mass), 0.71g of metavanadate (in V 2 O 5 Mass), 2.36g of polyvinylpyrrolidone was added to 150mL of a mixed solution of ethylene glycol/acetonitrile (ethylene glycol/acetonitrile volume 1:1), and then added to the above suspension, and the PH was adjusted to react for 1 hour; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 75℃for 4 hours and calcined in a muffle furnace at 560℃for 5 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Comparative example 9:
(1) Adding 53g H-BETA into 480g (NH) with mass concentration of 30% 4 ) 2 SO 4 Uniformly mixing, performing ion exchange at 85deg.C under high-speed magnetic stirring for 3.5 hr, washing the mixture with deionized water to neutrality, and drying at 80deg.C for 9 hr to obtain NH4+ -BETA carrier material; 42.4g NH was then added 4 + Adding BETA into 127g cerium nitrate solution with mass concentration of 3%, mixing, performing ion exchange under high-speed magnetic stirring at 70deg.C for 2 hr, washing the above mixture with deionized water to neutrality, drying at 90deg.C for 10 hr, and calcining at 500deg.C for 4.5 hr to obtain Ce-BETA molecular sieve prepared by liquid phase ion exchange method.
(2) Weighing 33.9g of Ce-BETA molecular sieve powder obtained in step (1), adding into 150mL of mixed solution of glycol/acetonitrile (volume ratio of glycol/acetonitrile 1:1) to form suspension, and magnetically stirring for 30min; 23.6g of a zirconium source (wherein zirconium chloride, zirconium sulfate and zirconium nitrate are 2.62g, 13.11 g and 7.87g, respectively, as ZrO 2 Mass), 2.83g of ammonium meta-molybdate (in MoO 3 Mass), 0.71g of metavanadate (in V 2 O 5 Mass), 2.36g of polyvinylpyrrolidone was added to 150mL of a mixed solution of ethylene glycol/acetonitrile (ethylene glycol/acetonitrile volume 1:1), and then added to the above suspension, and the PH was adjusted to react for 1 hour; after the reaction, the product was collected by filtration, washed three times with ethanol, dried at 75℃for 4 hours and calcined in a muffle furnace at 560℃for 5 hours.
(3) The fresh catalyst obtained above was evaluated after aging treatment, and the results are shown in Table 1.
Table 1 denitration performance table of denitration catalyst
Of course, the present invention is capable of other various embodiments and its several details are capable of modification and variation in light of the present invention by one skilled in the art without departing from the spirit and scope of the invention as defined in the appended claims.

Claims (13)

1. A denitration catalyst is characterized by having a core-shell structure, wherein the core comprises a molecular sieve, a metal component is loaded on the molecular sieve, a shell layer is a metal oxide, and the metal oxide at least comprises ZrO 2 The shell coats the core, and the metal oxide is bonded with the molecular sieve through chemical bonding.
2. The denitration catalyst according to claim 1, wherein the molecular sieve is one or more of SSZ-13 type molecular sieve, SAPO-34 type molecular sieve, LTA type molecular sieve, ZSM-5 type molecular sieve, BETA type molecular sieve, MCM-41 type molecular sieve, Y type molecular sieve, S-1 type molecular sieve, and TS-1 type molecular sieve; the metal component is one or more of Cu, fe, mn and Ce, and the metal component accounts for 1-20% of the total mass of the core.
3. The denitration catalyst of claim 1, wherein the metal oxide further comprises V 2 O 5 And/or MoO 2 The method comprises the steps of carrying out a first treatment on the surface of the The total mass of the shell layer accounts for 20% -80% of the total mass of the core.
4. A denitration catalyst according to claim 3, wherein V 2 O 5 Occupying ZrO in the shell layer 2 2 to 12 percent of MoO 2 Occupying ZrO in the shell layer 2 1 to 20 percent of the mass.
5. The preparation method of the denitration catalyst is characterized by comprising the following steps of:
step 1, carrying out ammonium ion exchange on a molecular sieve, and then carrying out ion exchange on the molecular sieve and a metal source;
step 2, mixing the molecular sieve obtained in the step 1 with an alkali solution, and performing surface treatment under the action of ultrasonic waves to expose binding sites on the surface of the molecular sieve;
and step 3, adding the shell metal precursor into the mixture obtained in the step 2, and adjusting the pH value to enable the shell metal precursor to react with the binding sites on the molecular sieve in a binding way, so as to obtain the denitration catalyst.
6. The method for preparing denitration catalyst according to claim 5, wherein the molecular sieve is subjected to ammonium ion exchange by adding the molecular sieve into an ammonium salt solution, and the ammonium salt is NH 4 Cl、NH 4 NO 3 、(NH 4 ) 2 SO 4 The mass concentration of the ammonium salt solution is 5-40%, and the solid-liquid mass ratio of the molecular sieve to the ammonium salt solution is 1:2-15.
7. The method for preparing a denitration catalyst according to claim 5, wherein in step 1, the step of ion-exchanging with the metal source is: mixing a molecular sieve obtained by ammonium ion exchange with a metal source solution, and performing ion exchange; the metal source is one or more of copper-containing salt, ferric salt, manganese-containing salt and cerium-containing salt, the mass concentration of the metal source solution is 0.5-10%, and the solid-liquid mass ratio of the molecular sieve to the metal source solution after ammonium ion exchange is 1:2-10.
8. The method for preparing a denitration catalyst according to claim 5, wherein step 2 is: mixing the molecular sieve obtained in the step 1 with an organic solvent, and then mixing with an alkali solution; the organic solvent is one or more of ethanol, glycol and acetonitrile, the mass concentration of the alkali solution is 0.5-2%, and the alkali is one of NaOH and KOH.
9. The method for preparing a denitration catalyst according to claim 5, wherein a pore-forming agent is added in the step 3, and the pore-forming agent is one or two of cetyl trimethyl ammonium bromide and polyvinylpyrrolidone.
10. The method for preparing a denitration catalyst according to claim 9, wherein the shell metal precursor comprises a zirconium precursor, and the zirconium precursor is one or more of zirconium chloride, zirconium nitrate and zirconium sulfate.
11. The method for preparing the denitration catalyst according to claim 10, wherein the shell metal precursor further comprises a molybdenum precursor and/or a vanadium precursor, wherein the molybdenum precursor is molybdic acid or ammonium meta-molybdate, and the vanadium precursor is vanadate or ammonium meta-vanadate; the zirconium precursor is ZrO 2 The vanadium precursor is expressed in terms of V by mass 2 O 5 Mass of the molybdenum precursor in MoO 3 The mass ratio of the total mass of the zirconium precursor, the vanadium precursor and the molybdenum precursor to the molecular sieve obtained in the step 1 is 1-4:5, and the mass ratio of the zirconium precursor, the vanadium precursor and the molybdenum precursor is 100 (2-12) to 1-20.
12. The method for preparing a denitration catalyst according to claim 10, wherein the mass ratio of the addition amount of the pore-forming agent to the zirconium precursor is 0.2 to 5:10.
13. The method for preparing a denitration catalyst according to claim 7, wherein the metal source is one or more of acetate, chloride and nitrate of Cu, fe, mn or Ce.
CN202210807293.9A 2022-07-07 2022-07-07 Denitration catalyst and preparation method thereof Pending CN117399056A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117839753A (en) * 2024-03-07 2024-04-09 交通运输部天津水运工程科学研究所 Denitration catalyst and preparation method and application thereof

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN117839753A (en) * 2024-03-07 2024-04-09 交通运输部天津水运工程科学研究所 Denitration catalyst and preparation method and application thereof
CN117839753B (en) * 2024-03-07 2024-05-07 交通运输部天津水运工程科学研究所 Denitration catalyst and preparation method and application thereof

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