阅读说明：本技术 抗碱金属与重金属中毒的离子交换型蒙脱土基脱硝催化剂及其制备方法 (Ion exchange type montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning and preparation method thereof ) 是由 张登松 王芃芦 周佳伦 陈阿玲 颜婷婷 于 2021-01-12 设计创作，主要内容包括：本发明公开了一种离子交换型蒙脱土基脱硝催化剂及其制备方法,该催化剂具备优异的抗碱金属与重金属中毒的性能。该脱硝催化剂主要通过稀酸对蒙脱土原矿进行改性,并将溶胶-凝胶法制得的二氧化钛前驱体加入酸改性的蒙脱土悬浮液中,经过高温煅烧获得二氧化钛柱撑的蒙脱土催化剂。最后通过离子交换法将活性金属离子交换到柱撑后的蒙脱土上从而得到催化剂。本发明中的催化剂具有原料价格低廉、制备方法简单、脱硝性能优异、抗烧结能力强和抗碱金属与重金属中毒性能好等优点,可用于生物质燃料锅炉、燃煤电厂、玻璃厂、垃圾焚烧厂等含碱/重金属飞灰的固定源烟气脱硝。(The invention discloses an ion exchange type montmorillonite-based denitration catalyst and a preparation method thereof. The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali metal and heavy metal poisoning resistance and the like, and can be used for denitration of fixed source flue gas containing alkali/heavy metal fly ash in biomass fuel boilers, coal-fired power plants, glass plants, garbage incineration plants and the like.)

1. An ion exchange type montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning is characterized in that: the montmorillonite modified by dilute acid and supported by titanium dioxide column is used as an ion exchange material, and different exchanged metal ions are used as active components.

2. The ion-exchange type montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning according to claim 1, characterized in that: the dilute acid is at least one of hydrochloric acid, nitric acid and sulfuric acid.

3. The ion-exchange type montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning according to claim 1, characterized in that: the metal ions are at least one of copper ions, iron ions, cerium ions, manganese ions, cobalt ions and chromium ions.

4. A method for preparing the ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning according to claim 1, which is characterized in that: the method comprises the following steps:

a. the preparation of the titanium dioxide pillared montmorillonite by dilute acid modification:

adding raw montmorillonite ore into dilute acid, carrying out oil bath stirring for 3-5 hours at 80-100 ℃ to wash out impurity ions including Na, Mg and Ca in the raw montmorillonite ore, carrying out suction filtration until acid radical ions and separated impurity ions are cleaned, drying a filter cake after suction filtration at 70-80 ℃ overnight, and grinding for later use;

dropwise adding a titanium source into a dilute acid solution under vigorous stirring, wherein the molar ratio of titanium to dilute acid is 1-5, and after dropwise adding is finished, continuously stirring at room temperature for 12-24 hours to prepare a titanium dioxide pillared solution;

stirring the acid modified montmorillonite in deionized water at room temperature for 12-24 hours to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to water is 1-2 g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into a montmorillonite suspension, carrying out oil bath stirring at the temperature of 60-80 ℃ for 5-7 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at the temperature of 70-80 ℃ overnight, grinding, and calcining at the temperature of 350-500 ℃ for 4-5 hours to prepare acid-modified titanium dioxide pillared montmorillonite;

b. dilute acid modification and titanium dioxide pillared montmorillonite ion exchange modification:

dispersing the acid-modified titanium dioxide pillared montmorillonite obtained after calcination in the step a into a metal salt solution, carrying out oil bath stirring for 5-7 hours at the temperature of 60-80 ℃, separating the solid from the solution through centrifugal separation, washing the obtained solid for 5-7 times, drying the solid at the temperature of 70-80 ℃ overnight, and calcining the solid at the temperature of 350-500 ℃ for 4-5 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning.

5. The method for preparing an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning according to claim 4, wherein: in the step a, the titanium source is at least one of tetra-n-butyl titanate, titanium tetrachloride and titanyl sulfate.

6. The method for preparing an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning according to claim 4, wherein: in the step a, the concentration of the dilute acid solution is 1-5 mol/L, and the ratio of titanium to soil is 5-15 mmol/g.

7. The method for preparing an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning according to claim 4, wherein: in the step b, the metal salt is at least one of copper salt, iron salt, cerium salt, manganese salt, cobalt salt and chromium salt.

8. The method for preparing an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning according to claim 7, wherein: the copper salt is at least one of copper nitrate, copper acetate and copper chloride;

or the ferric salt is at least one of ferric nitrate, ferric acetate and ferric chloride;

or the cerium salt is at least one of cerium nitrate, cerium acetate and cerium chloride;

or the manganese salt is at least one of manganese nitrate, manganese acetate and manganese chloride;

or the cobalt salt is at least one of cobalt nitrate, cobalt acetate and cobalt chloride;

or the chromium salt is at least one of chromium nitrate, chromium acetate and chromium chloride.

Technical Field

The invention relates to a denitration catalyst and a preparation method thereof, in particular to an ion exchange type montmorillonite-based denitration catalyst and a preparation method thereof, which are applied to the technical field of nitrogen oxide control and purification in environmental protection.

Background

Nitrogen Oxides (NO) produced in coal combustion flue gas_x) Including NO, NO₂、N₂O, is extremely harmful to human and ecological systems, can cause urban smog, acid rain and ozone depletion, and is still one of the main environmental problems at present. Currently, the industry primarily reduces the fixed source NO by Selective Catalytic Reduction (SCR) techniques_xDischarge of (2) at V₂O₅-WO₃/MoO₃-TiO₂For commercial denitration catalysts, it is converted to nitrogen and water. Although vanadium-based catalysts have high activity, their disadvantages, such as biotoxicity, high SO, remain significant₂Oxidation to SO₃Activity, narrow temperature window (300-400 ℃), and the like.

In recent years, CeO is used₂Excellent oxygen storage capacity and excellent redox performance, Ce-based catalysts are widely studied as catalysts that may replace V-based commercial catalysts. Wherein, CeO taking montmorillonite (MMT) as carrier₂The MMT supported catalyst is receiving increasing attention due to wide material source and low cost. However, the catalyst still has certain disadvantages, such as CeO loaded on the surface of montmorillonite₂The catalyst is easy to sinter at high temperature, so that active components are agglomerated, and the performance of the catalyst is influenced; montmorillonite does not have strong acidity, and the performance of montmorillonite used as a carrier is poor. Meanwhile, alkali/heavy metals (K, Na, Ca, As, Pb and the like) in the industrial flue gas occupy acid sites on the catalyst, so that the adsorption of ammonia is reduced, the SCR catalyst has a poisoning effect, and the activity of the catalyst is reduced. The active component of the supported catalyst is positioned on the outer surface of the carrier, so that the supported catalyst is very easy to be attacked by alkali/heavy metal ions to cause the deactivation of the catalyst. Therefore, the method develops the dehydration with low price, excellent activity at medium and low temperature, sintering resistance and alkali/heavy metal co-poisoning resistanceThe nitro catalyst has important significance.

CN106423192A discloses a method for supporting interlayer column by using layered montmorillonite as carrier and selecting different metals and loading gamma-MnO₂A low-temperature denitration catalyst as an active component. However, MnSO is used in the preparation of the catalyst₄·H₂O and (NH)₄)₂S₂O₈Reacting to obtain an active component gamma-MnO₂The effect of sulfate residues on the catalyst activity cannot be excluded. Meanwhile, the catalyst is obtained without calcination, active components can be sintered and even subjected to crystal transformation in the medium-high temperature reaction process, and the stability is poor. In addition, the active components of the catalyst are exposed on the surface of the carrier and are seriously poisoned by alkali/heavy metal in flowing gas, and the invention patent does not relate to the research of the aspect. CN102225335A relates to a flue gas denitration catalyst and a preparation method thereof, wherein the loading capacity of the active component copper of the catalyst is 5-10 wt% calculated by CuO, and the loading capacity of the auxiliary agent cerium is CeO₂The amount is 1 to 2 wt%. However, the catalyst is mainly prepared by adopting a loading mode, the specific surface area of the catalyst is low, the acid sites are insufficient, the denitration performance of the catalyst is researched only at a low space velocity, and the activity of the catalyst after alkali/heavy metal poisoning is not involved.

Disclosure of Invention

The invention aims to overcome the defects of the prior art and provides an ion exchange type montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning and a preparation method thereof. The catalyst developed by the invention enhances the alkali/heavy metal resistance of the catalyst on the basis of ensuring the excellent medium and low temperature activity of the catalyst, and can greatly prolong the service life of the catalyst in fixed source flue gas denitration.

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

an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning takes montmorillonite modified by dilute acid and supported by titanium dioxide columns as an ion exchange material and takes different exchanged metal ions as active components. The dispersion degree of the active components is improved, and the catalytic activity and alkali/heavy metal tolerance of the catalyst are also greatly improved.

As a preferable technical scheme of the invention, the dilute acid is at least one of hydrochloric acid, nitric acid and sulfuric acid.

In a preferred embodiment of the present invention, the metal ion is at least one of a copper ion, an iron ion, a cerium ion, a manganese ion, a cobalt ion, and a chromium ion.

The invention relates to a preparation method of an ion exchange type montmorillonite-based denitration catalyst capable of resisting alkali metal and heavy metal poisoning, which comprises the following steps:

a. the preparation of the titanium dioxide pillared montmorillonite by dilute acid modification:

adding raw montmorillonite ore into dilute acid, carrying out oil bath stirring for 3-5 hours at 80-100 ℃ to wash out impurity ions including Na, Mg and Ca in the raw montmorillonite ore, carrying out suction filtration until acid radical ions and separated impurity ions are cleaned, drying a filter cake after suction filtration at 70-80 ℃ overnight, and grinding for later use;

dropwise adding a titanium source into a dilute acid solution under vigorous stirring, wherein the molar ratio of titanium to dilute acid is 1-5, and continuously stirring at room temperature for 12-24 hours after dropwise adding is finished to prepare a titanium dioxide pillared solution;

stirring the acid modified montmorillonite in deionized water at room temperature for 12-24 hours to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to water is 1-2 g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into a montmorillonite suspension, carrying out oil bath stirring at the temperature of 60-80 ℃ for 5-7 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at the temperature of 70-80 ℃ overnight, grinding, and calcining at the temperature of 350-500 ℃ for 4-5 hours to prepare acid-modified titanium dioxide pillared montmorillonite;

b. dilute acid modification and titanium dioxide pillared montmorillonite ion exchange modification:

dispersing the acid-modified titanium dioxide pillared montmorillonite obtained after calcination in the step a into a metal salt solution, carrying out oil bath stirring for 5-7 hours at the temperature of 60-80 ℃, separating the solid from the solution through centrifugal separation, washing the obtained solid for 5-7 times, drying the solid at the temperature of 70-80 ℃ overnight, and calcining the solid at the temperature of 350-500 ℃ for 4-5 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

Preferably, in the step a, the titanium source is at least one of tetra-n-butyl titanate, titanium tetrachloride and titanyl sulfate.

Preferably, in the step a, the concentration of the dilute acid solution is 1-5 mol/L, and the ratio of titanium to soil is 5-15 mmol/g.

Preferably, in the step b, the metal salt is at least one of copper salt, iron salt, cerium salt, manganese salt, cobalt salt and chromium salt.

Preferably, the copper salt is at least one of copper nitrate, copper acetate and copper chloride; preferably, the ferric salt is at least one of ferric nitrate, ferric acetate and ferric chloride; preferably, the cerium salt is at least one of cerium nitrate, cerium acetate and cerium chloride; preferably, the manganese salt is at least one of manganese nitrate, manganese acetate and manganese chloride; preferably, the cobalt salt is at least one of cobalt nitrate, cobalt acetate and cobalt chloride; preferably, the chromium salt is at least one of chromium nitrate, chromium acetate and chromium chloride.

Compared with the prior art, the invention has the following obvious and prominent substantive characteristics and remarkable advantages:

1. the denitration catalyst takes the montmorillonite modified by dilute acid and supported by titanium dioxide columns as an ion exchange material, so that the specific surface area and the surface acid sites of the montmorillonite are greatly increased through acid treatment and column support modification, the capture capability of the montmorillonite on alkali/heavy metal is enhanced, and the activity and the alkali/heavy metal resistance of the montmorillonite are improved;

2. the denitration catalyst exchanges active components to ion exchange sites among montmorillonite layers in an ion exchange mode, so that the active components are not easy to sinter, and meanwhile, abundant cation exchange sites among the montmorillonite layers can anchor alkali/heavy metal ions in flowing gas, so that the influence of the alkali/heavy metal ions on the active components is reduced, and the alkali/heavy metal resistance of the catalyst is improved;

3. the catalyst disclosed by the invention has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Drawings

FIG. 1 shows Ce exchanged TiO prepared in example 1 of the present invention₂SEM image of pillared acid montmorillonite catalyst.

Detailed Description

The above-described scheme is further illustrated below with reference to specific embodiments, which are detailed below:

example 1

In this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite:

adding montmorillonite raw ore into 3mol/L dilute nitric acid, performing oil bath stirring at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, performing suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 2.04g of tetrabutyl titanate into 5.5mL of 3mol/L dilute nitric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite in 100mL of 0.05mol/L cerium nitrate solution, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid with water for 5-7 times, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

Experimental test analysis:

testing the denitration performance of the catalyst: granulating the prepared catalyst into 20-40 meshes, putting the granules into a reaction furnace for activity and N₂Selectivity test, reaction temperature of 270 ℃ and 450 ℃ and space velocity of 50000m³·g^-1·h^-1The denitration efficiency is stabilized to be more than 90 percent under the condition of (1), N₂The O yield was less than 10 ppm. Simulated flue gas is O₂5％，NO 500ppm，NH₃500 ppm，N₂Is diluent gas. The catalyst sample was tested, and FIG. 1 shows Ce exchanged TiO prepared in this example₂SEM image of pillared acid montmorillonite catalyst, it can be seen that the Ce exchanged TiO prepared in this example₂The pillared acid montmorillonite catalyst has an obvious layered structure.

Alkali metal poisoning resistance test: 1% potassium nitrate is loaded on the catalyst by adopting a dipping method, and the simulated poisoned catalyst obtained after calcining for 4 hours at 400 ℃ is subjected to SCR denitration activity test, wherein the reaction temperature is 300-450 ℃, and the space velocity is 50000m³·g^-1·h^-1The denitration efficiency is stabilized to be more than 80 percent under the condition of (1), N₂The amount of O produced is very small. The catalyst of the embodiment is a selective reduction denitration catalyst with good performance, and simultaneously has high alkali/heavy metal resistance, and the catalyst can improve the poisoning effect when alkali/heavy metal coexists. The true bookThe embodiment catalyst enhances the alkali/heavy metal resistance of the catalyst on the basis of ensuring excellent medium and low temperature activity of the catalyst, and can greatly prolong the service life of the catalyst in fixed source flue gas denitration. The catalyst has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 2

This embodiment is substantially the same as embodiment 1, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite: adding montmorillonite raw ore into 3mol/L dilute nitric acid, performing oil bath stirring at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, performing suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 2.04g of tetrabutyl titanate into 5.5mL of 3mol/L dilute nitric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite in 100mL of 0.05mol/L copper nitrate solution, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid with water for 5-7 times, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst in the embodiment has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 3

This embodiment is substantially the same as the previous embodiment, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite: adding montmorillonite raw ore into 3mol/L dilute nitric acid, performing oil bath stirring at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, performing suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 2.04g of tetrabutyl titanate into 5.5mL of 3mol/L dilute nitric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite in 100mL of 0.05mol/L ferric nitrate solution, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid with water for 5-7 times, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst in the embodiment has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 4

This embodiment is substantially the same as the previous embodiment, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite: adding montmorillonite raw ore into 3mol/L dilute nitric acid, performing oil bath stirring at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, performing suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 2.04g of tetrabutyl titanate into 5.5mL of 3mol/L dilute nitric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite into 100mL of 0.05mol/L manganese nitrate solution, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid with water for 5-7 times, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst in the embodiment has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 5

This embodiment is substantially the same as the previous embodiment, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite: adding montmorillonite raw ore into 3mol/L dilute nitric acid, performing oil bath stirring at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, performing suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 2.04g of tetrabutyl titanate into 5.5mL of 3mol/L dilute nitric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite into 100mL of 0.05mol/L mixed solution of ferric nitrate and cerium nitrate, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid for 5-7 times with water, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst in the embodiment has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 6

This embodiment is substantially the same as the previous embodiment, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite: adding montmorillonite raw ore into 3mol/L dilute nitric acid, performing oil bath stirring at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, performing suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 2.04g of tetrabutyl titanate into 5.5mL of 3mol/L dilute nitric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite into 100mL of 0.05mol/L mixed solution of copper nitrate and cerium nitrate, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid for 5-7 times with water, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst in the embodiment has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 7

This embodiment is substantially the same as the previous embodiment, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with hydrochloric acid, and preparing titanium dioxide pillared montmorillonite: adding montmorillonite raw ore into 3mol/L dilute hydrochloric acid, stirring in oil bath at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, then carrying out suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 2.04g of tetrabutyl titanate into 5.5mL of 3mol/L dilute hydrochloric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring montmorillonite modified by hydrochloric acid in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare hydrochloric acid modified titanium dioxide pillared montmorillonite;

hydrochloric acid modification and ion exchange modification of titanium dioxide pillared montmorillonite: dispersing 1g of calcined hydrochloric acid modified and titanium dioxide pillared montmorillonite in 100mL of 0.05mol/L cerium nitrate solution, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid with water for 5-7 times, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst in the embodiment has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 8

This embodiment is substantially the same as the previous embodiment, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite: adding montmorillonite raw ore into 3mol/L dilute nitric acid, performing oil bath stirring at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, performing suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding a titanium tetrachloride solution into a dilute nitric acid solution of 3mol/L under vigorous stirring, wherein the molar ratio of titanium tetrachloride to nitric acid is 3, and continuously stirring at room temperature for 12 hours after the dropwise addition is finished to prepare a titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite in 100mL of 0.05mol/L cerium nitrate solution, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid with water for 5-7 times, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst in the embodiment has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 9

This embodiment is substantially the same as the previous embodiment, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite: adding montmorillonite raw ore into 3mol/L dilute nitric acid, performing oil bath stirring at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the montmorillonite raw ore, performing suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 3.4g of tetrabutyl titanate into 9.17mL of 3mol/L dilute nitric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite in 100mL of 0.05mol/L cerium nitrate solution, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid with water for 5-7 times, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged to the pillared montmorillonite by an ion exchange method to obtain the catalyst. The catalyst in the embodiment has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

Example 10

This embodiment is substantially the same as the previous embodiment, and is characterized in that:

in this embodiment, a preparation method of an ion-exchange montmorillonite-based denitration catalyst resistant to alkali metal and heavy metal poisoning includes the following steps:

modifying with nitric acid, and preparing titanium dioxide pillared montmorillonite: adding raw montmorillonite ore into 5mol/L dilute nitric acid, stirring in an oil bath at 90 ℃ for 4 hours to wash out impurity ions including Na, Mg and Ca in the raw montmorillonite ore, then carrying out suction filtration until acid radical ions and the separated impurity ions are cleaned, drying a filter cake after suction filtration at 70 ℃ overnight, and grinding for later use;

dropwise adding 2.04g of tetrabutyl titanate into 5.5mL of 3mol/L dilute nitric acid solution under vigorous stirring, and continuously stirring at room temperature for 12 hours after dropwise adding is finished to prepare titanium dioxide pillared solution;

stirring the nitric acid modified montmorillonite in deionized water for 12 hours at room temperature to ensure that the montmorillonite fully absorbs water and swells, wherein the ratio of the montmorillonite to the water is 1g/100 mL;

dropwise adding the prepared titanium dioxide pillared liquid into 1% montmorillonite suspension, carrying out oil bath stirring at 60 ℃ for 6 hours, then carrying out centrifugal separation on the solid and the solution, centrifugally washing the obtained precipitate for 5-7 times, drying at 70 ℃ overnight, grinding, and calcining at 400 ℃ for 4 hours to prepare nitric acid modified titanium dioxide pillared montmorillonite;

modifying by nitric acid and ion exchange of titanium dioxide pillared montmorillonite: dispersing 1g of calcined nitric acid modified titanium dioxide pillared montmorillonite in 100mL of 0.05mol/L cerium nitrate solution, carrying out oil bath stirring at 60 ℃ for 6 hours, separating the solid from the solution through centrifugal separation, washing the obtained solid with water for 5-7 times, drying at 70 ℃ overnight, and calcining at 400 ℃ for 4 hours by using a muffle furnace to obtain a product, namely the ion exchange type montmorillonite-based catalyst resistant to alkali metal and heavy metal poisoning.

The denitration catalyst is mainly characterized in that raw montmorillonite ore is modified by dilute acid, a titanium dioxide precursor prepared by a sol-gel method is added into acid-modified montmorillonite suspension, and the titanium dioxide pillared montmorillonite catalyst is obtained by high-temperature calcination. Finally, active metal ions are exchanged between the pillared montmorillonite layers by an ion exchange method to obtain the catalyst. The catalyst disclosed by the invention has the advantages of low raw material price, simple preparation method, excellent denitration performance, strong sintering resistance, good alkali/heavy metal resistance and the like, and can be used for denitration of tail gas of a biomass fuel boiler, a coal-fired power plant, a glass plant, a garbage incineration plant and other fixed source containing alkali/heavy metal fly ash.

The embodiments of the present invention have been described with reference to the accompanying drawings, but the present invention is not limited to the embodiments, and various changes and modifications can be made according to the purpose of the invention, and any changes, modifications, substitutions, combinations or simplifications made according to the spirit and principle of the technical solution of the present invention shall be equivalent substitution ways, as long as the purpose of the present invention is met, and the ion exchange type anti-poisoning montmorillonite-based denitration catalyst and the preparation method thereof shall fall within the protection scope of the present invention without departing from the technical principle and inventive concept of the present invention.