阅读说明：本技术 一种Mn2O3-SMS低温脱硝催化剂及其制备方法 (Mn2O3-SMS low-temperature denitration catalyst and preparation method thereof ) 是由 李丽绒 薛达 杨彦群 王浩 张超 李昂 于 2020-06-24 设计创作，主要内容包括：本发明属于煤化工催化剂制备技术领域,具体涉及一种Mn<Sub>2</Sub>O<Sub>3</Sub>-SMS低温脱硝催化剂及其制备方法；所述Mn<Sub>2</Sub>O<Sub>3</Sub>/SMS低温脱硝催化剂材料由上表层纺粘材料、中间层熔喷材料、下表层纺粘材料以及附着和镶嵌在各层材料间的活性组分Mn<Sub>2</Sub>O<Sub>3</Sub>构成,其中,Mn<Sub>2</Sub>O<Sub>3</Sub>质量百分比含量为20-80；方法为,将活性组分Mn<Sub>2</Sub>O<Sub>3</Sub>粉末与聚丙烯腈PAN粉末混合,依次经过纺粘、熔喷、纺粘三次纺丝并经针刺加固复合处理合成Mn<Sub>2</Sub>O<Sub>3</Sub>/SMS复合材料,最后在75-105℃下干燥即得到Mn<Sub>2</Sub>O<Sub>3</Sub>/SMS低温脱硝催化剂；本发明制备方法简单、实施成本低、易于工业化应用,可以满足市场的大量需求,同时由于采用多层复合结构的聚合物纤维作为载体,其内部结构具有柔韧性高、孔隙丰富,可提高催化剂的催化能力和反应效率。(The invention belongs to the technical field of preparation of coal chemical industry catalysts, and particularly relates to Mn 2 O 3 -SMS low temperature denitration catalyst and method of preparation thereof; the Mn is 2 O 3 the/SMS low-temperature denitration catalyst material comprises an upper surface layer spun-bonded material, a middle layer melt-blown material, a lower surface layer spun-bonded material and an active component Mn attached and embedded among the materials of the layers 2 O 3 In which Mn is 2 O 3 The mass percentage content is 20-80; the method comprises the steps of mixing an active component Mn 2 O 3 Mixing the powder with polyacrylonitrile PAN powder, and sequentially passing throughThrough spinning of spun bond, melt-blown spinning and spun bond for three times, and synthesizing Mn through needling reinforcement composite treatment 2 O 3 Drying the composite material at 75-105 deg.C to obtain Mn 2 O 3 SMS low temperature denitration catalyst; the preparation method is simple, low in implementation cost and easy for industrial application, can meet a large number of market demands, and simultaneously has high flexibility and rich pores in the internal structure due to the adoption of the polymer fiber with the multilayer composite structure as the carrier, so that the catalytic capability and the reaction efficiency of the catalyst can be improved.)

1. Mn (manganese)₂O₃-SMS low temperature denitration catalyst, characterized in that said Mn is₂O₃the/SMS low-temperature denitration catalyst material comprises an upper surface layer spun-bonded material, a middle layer melt-blown material, a lower surface layer spun-bonded material and an active component Mn attached and embedded among the materials of the layers₂O₃In which Mn is₂O₃The mass percentage content is 20-80%.

2. A Mn according to claim 1₂O₃-SMS low temperature denitration catalyst, characterized in that the upper and lower surface layer spun-bonded materials have a fiber diameter of 1-100 μm and an areal density of 5-500 g/m²The fiber diameter of the melt-blown material of the middle layer is 0.3-20 mu m, and the surface density is 5-200 g/m²。

3. Preparation of Mn as claimed in claim 1₂O₃Method for preparing SMS low-temperature denitration catalyst, characterized in that active component Mn₂O₃Mixing the powder with polyacrylonitrile PAN powder, sequentially carrying out spun-bonding, melt-blowing and spun-bonding for three times, and carrying out needling reinforcement composite treatment to synthesize Mn₂O₃Drying the composite material at 75-105 deg.C to obtain Mn₂O₃/SMS low-temperature denitration catalyst.

4. A method of producing Mn according to claim 3₂O₃-SMS low temperature denitration catalyst method, characterized in that the mass ratio of Mn2O3 powder mixed with polyacrylonitrile PAN powder is 4: 1-1: 4.

5. a method of producing Mn according to claim 3₂O₃-method of SMS low temperature denitration catalyst, characterized in that the melt-blown spinning process parameters are: the material temperature is 120-; the technological parameters of the two-time spun-bonded spinning process are as follows: melt body temperatureThe temperature is 150 ℃ and 230 ℃, the lateral blowing temperature is 15-25 ℃, and the receiving distance is 5-28 cm.

6. A method of producing Mn according to claim 3₂O₃The method for preparing the SMS low-temperature denitration catalyst is characterized in that the fiber web is processed by adopting a common needle and a single-needle-plate lower-piercing manner in the needling reinforcement, the fiber web is pierced in a vertical needling manner, the needling depth is 6-18mm, and the needling density is 4000-12000 punches/cm²。

7. The method for preparing the Mn2O3-SMS low-temperature denitration catalyst according to claim 3, wherein the spun-bonded material is one of PAN, PVDF and PVA.

8. The method for preparing Mn2O3-SMS low-temperature denitration catalyst according to claim 3, wherein the melt-blown material is one of PAN, PVDF and PVA.

Technical Field

The invention belongs to the technical field of preparation of coal chemical industry catalysts, and particularly relates to Mn₂O₃An SMS low-temperature denitration catalyst and a preparation method thereof.

Background

China, the largest coal consuming country in the world, accounts for over 50% of the coal consumption in 2017. The current situation and characteristics of the Chinese energy structure are rich coal, poor oil and less gas, and the energy structure mainly based on coal still cannot be changed in the next decades. However, in the exhaust gas after coal combustion, NO_xNot only does it corrode equipment and piping, causing poisoning of the catalyst during subsequent shift, reforming, and synthesis processes, but it also can be a serious environmental pollution after being discharged into the atmosphere. Thus, NO_xThe high-efficiency removal of the coal is an important precondition for realizing the clean and high-efficiency conversion of the coal.

The main problems of the existing low-temperature denitration catalyst are that ammonium sulfate or ammonium bisulfate is poisoned and inactivated, and the denitration rate is obviously reduced. The reason why the catalyst is deactivated by the poisoning of ammonium sulfate or ammonium bisulfate is that NH in the flue gas is generated at low temperature₃、H₂O、SO₂The ammonia sulfate or the ammonium bisulfate is easily formed by being adsorbed on the surface of the catalyst, the temperature of the flue gas is too low and does not reach the decomposition temperature of the ammonia sulfate or the ammonium bisulfate in the pore channels of the catalyst, and a great amount of ammonia sulfate or sulfur can be accumulated on the surface of the catalyst after the catalyst runs for a long timeAmmonium hydrogen carbonate, thereby sharply decreasing the denitration rate of the catalyst, resulting in deactivation of the catalyst.

Disclosure of Invention

The invention provides Mn for solving the technical problem that the existing low-temperature denitration catalyst is easy to generate ammonium sulfate or ammonium bisulfate poisoning to cause catalyst inactivation₂O₃An SMS low-temperature denitration catalyst and a preparation method thereof.

In order to solve the technical problems, the technical scheme adopted by the invention is as follows:

mn (manganese)₂O₃-SMS Low temperature denitration catalyst, said Mn₂O₃the/SMS low-temperature denitration catalyst material comprises an upper surface layer spun-bonded material, a middle layer melt-blown material, a lower surface layer spun-bonded material and an active component Mn attached and embedded among the materials of the layers₂O₃In which Mn is₂O₃The mass percentage content is 20-80%.

Further, the above spunbond materials of the upper and lower surface layers have a fiber diameter of 1 to 100 μm and an areal density of 5 to 500 g/m²The fiber diameter of the melt-blown material of the middle layer is 0.3-20 mu m, and the surface density is 5-200 g/m²。

Preparation of the Mn₂O₃The SMS low-temperature denitration catalyst is prepared by adding Mn as an active component₂O₃Mixing the powder with polyacrylonitrile PAN powder, sequentially carrying out spun-bonding, melt-blowing and spun-bonding for three times, and carrying out needling reinforcement composite treatment to synthesize Mn₂O₃Drying the composite material at 75-105 deg.C to obtain Mn₂O₃/SMS low-temperature denitration catalyst.

Further, the mass ratio of the mixed Mn2O3 powder to polyacrylonitrile PAN powder is 4: 1-1: 4.

in the above preparation method, the concrete process steps of the spun-bonding are to prepare the upper and lower layers of spun-bonded spinning materials of the Mn2O3/SMS low-temperature denitration catalyst by using a spun-bonded spinning device for the mixture powder and using methods commonly used in the art, which are not described herein too much.

In the above preparation method, the specific process steps of melt-blowing are to use a melt-blowing spinning device to prepare the upper and lower spunbond spinning materials of the Mn2O3/SMS low-temperature denitration catalyst by using methods commonly used in the art, which are not described herein.

Further, the melt-blown spinning process has the following technological parameters: the material temperature is 120-; the technological parameters of the two-time spun-bonded spinning process are as follows: the melt temperature is 150-230 ℃, the side blowing temperature is 15-25 ℃, and the receiving distance is 5-28 cm.

Further, the needle punching reinforcement adopts the common needle and the lower piercing mode of a single needle plate to process the fiber web, the fiber web is pierced by a vertical needle punching mode, the needle punching depth is 6-18mm, and the needle punching density is 4000-²。

Further, the spun-bonded material is one of PAN, PVDF and PVA.

Further, the melt-blown material is one of PAN, PVDF and PVA.

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

(1) the catalyst adopts the multilayer polymer composite material SMS as a carrier, and the rich pore structure of the SMS composite material can promote the catalytic reaction while providing the support effect for the active component. In addition, the SMS has excellent mechanical property and flexibility, has a flexible structure with multi-layer and multi-stage limited-area pores, can optimize the texture, limit the movement of active components, further reduce the aggregation of the active components, fully exert the nanometer effect of the material, realize the enhancement of the gas-solid reaction rate and the mass transfer efficiency, and improve the catalytic efficiency of a unit catalyst.

(2) The preparation method of the catalyst has the advantages of simple process route, low implementation cost and easy industrial popularization, and can meet a large amount of demands of the market.

(3) The method for preparing the catalyst can improve the chemical reaction efficiency, greatly shorten the time required by the reaction and reduce the time cost for preparing the catalyst. Mn prepared by the method of the present invention was tested₂O₃The denitration catalytic efficiency of the/SMS catalyst is maintained to be more than 99.8 percent.

Drawings

FIG. 1 is a spunbond-meltblown-spunbond apparatus used in the present invention.

Detailed Description

The present invention is further illustrated by the following specific examples.