阅读说明：本技术 一种适用于低浓度大风量有机挥发物的催化剂及制备方法 (Catalyst suitable for low-concentration large-air-volume organic volatile matters and preparation method thereof ) 是由 李建 石应杰 赵佳佳 王洪昌 朱金伟 束韫 田刚 于 2021-10-11 设计创作，主要内容包括：本发明提供一种适用于低浓度大风量有机挥发物的催化剂及制备方法,涉及催化剂技术领域。包括以下步骤：S1、将粉煤灰、电解锰渣和钒钛钢渣按质量比混合,然后按质量比加入NaOH溶液将其润湿,研磨均匀后,经微波联合热辐射焙烧后获得焙烧产物；S2、将所述焙烧后产物按顺序加入去离子水、四丙基氢氧化铵或四丙基溴化铵、乙醇和聚季铵盐,并超声加热混匀一定时间,经加热搅拌至凝胶；S3、将步骤S2中的凝胶物转移至反应釜中,再次经微波联合热辐射法晶化后,然后进行过滤、洗涤、干燥和焙烧即得到催化剂。本发明通过该催化材料成功制备,可提高粉煤灰、电解锰渣和钒钛钢渣固体废弃物利用价值,同时制备的催化剂也提高了低浓度大风量有机挥发物的去除率。(The invention provides a catalyst suitable for low-concentration large-air-volume organic volatile matters and a preparation method thereof, and relates to the technical field of catalysts. The method comprises the following steps: s1, mixing the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag according to a mass ratio, adding a NaOH solution according to the mass ratio to wet the mixture, uniformly grinding the mixture, and roasting the mixture by microwave and heat radiation to obtain a roasted product; s2, sequentially adding deionized water, tetrapropylammonium hydroxide or tetrapropylammonium bromide, ethanol and polyquaternium into the roasted product, ultrasonically heating and uniformly mixing for a certain time, and heating and stirring to obtain gel; s3, transferring the gel in the step S2 to a reaction kettle, crystallizing by a microwave combined thermal radiation method, filtering, washing, drying and roasting to obtain the catalyst. The catalyst is successfully prepared by the catalytic material, so that the utilization value of the solid wastes of the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag can be improved, and the removal rate of low-concentration and high-air-volume organic volatile matters is improved by the prepared catalyst.)

1. A preparation method suitable for a low-concentration large-air-volume organic volatile catalyst is characterized by comprising the following steps of: the method comprises the following steps:

s1, mixing the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag according to a mass ratio, adding a NaOH solution according to the mass ratio to wet the mixture, uniformly grinding the mixture, and roasting the mixture by microwave and heat radiation to obtain a roasted product;

s2, sequentially adding deionized water, tetrapropylammonium hydroxide or tetrapropylammonium bromide, ethanol and polyquaternium into the roasted product, ultrasonically heating and uniformly mixing, and heating and stirring to obtain gel;

s3, transferring the gel in the step S2 to a reaction kettle, crystallizing by a microwave combined thermal radiation method, filtering, washing, drying and roasting to obtain the catalyst.

2. The method for preparing the catalyst for the organic volatile matters with low concentration and large air volume according to claim 1, which is characterized in that: in the step S1, the mass ratio of the fly ash to the electrolytic manganese slag to the vanadium-titanium steel slag is (1-10): (5-10): (4-8), mixing the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag to form mixed solid waste, wherein the fly ash can be replaced by coal gangue and slag.

3. The method for preparing the catalyst for the organic volatile matters with low concentration and large air volume according to claim 2, which is characterized in that: the mass ratio of the mixed solid waste to the NaOH solution is 1 (0.5-2).

4. The method for preparing the catalyst for the organic volatile matters with low concentration and large air volume according to claim 3, which is characterized in that: the mass concentration of the NaOH solution is 10-40%.

5. The method for preparing the catalyst for the organic volatile matters with low concentration and large air volume according to claim 1, which is characterized in that: the temperature of the microwave combined heat radiation in the step S1 is 600-800 ℃, the microwave power is 400-600W, and the roasting time in the step S1 is 1-4 hours.

6. The method for preparing the catalyst for the organic volatile matters with low concentration and large air volume according to claim 1, which is characterized in that: the roasted product in the step S2, deionized water, tetrapropylammonium hydroxide or tetrapropylammonium bromide, ethanol and polyquaternium, wherein the ratio of the components is SiO₂Tetrapropylammonium hydroxide in a molar ratio of 100 to (20 to 30) or SiO₂The molar ratio of tetrapropylammonium bromide is 100 (20-30); SiO 2₂The mol ratio of the deionized water is 100 (2000-); ethanol: polyquaternium: SiO 2₂Mass ratio of (0.1-0.4): (0.1-0.4): 1.

7. the method for preparing the catalyst for the organic volatile matters with low concentration and large air volume according to claim 6, which is characterized in that: the SiO₂The silicon oxide compounds in the solid waste are obtained, and when the ultrasonic heating and mixing in the step S2 are carried out, the ultrasonic power is 100-300W, the ultrasonic time is 30-60min, the heating temperature is 40-70 ℃, and the stirring speed is 400-700 r/min.

8. The method for preparing the catalyst for the organic volatile matters with low concentration and large air volume according to claim 1, which is characterized in that: the power of the microwave combined heat radiation in the step S3 is 400-600W, the heating temperature is 140-200 ℃, and the crystallization time is 14-24 hours, then the solid powder obtained after the filtering, washing and drying in the step S3 is roasted at 400 ℃ of 300-6 hours, and then the catalyst is obtained at 700 ℃ of 500-8 hours.

9. The catalyst according to any one of claims 1 to 8, characterized in that: the general formula of the catalyst is Fe-Mn-V-Ti-m-MFI, wherein m-MFI is a micro mesoporous material with an MFI structure, and Fe, Mn, V and Ti are all framework atoms of m-MFI and transition metal oxide nanoclusters outside the framework.

10. The catalyst of claim 8, wherein: the catalyst has catalytic activity and stability for catalytic oxidation of oil smoke organic volatile matters, has certain water resistance, and has catalytic activity and stability for catalytic oxidation of chemical raw material medicine organic volatile matters.

Technical Field

The invention relates to the technical field of catalysts, in particular to a catalyst suitable for low-concentration large-air-volume organic volatile matters and a preparation method thereof.

Background

The solid wastes such as fly ash, coal gangue, electrolytic manganese slag, vanadium-titanium steel slag and the like in China have high yield, wherein the fly ash is the main solid waste of a power plant. According to estimation, the yield of the fly ash in China is nearly 9 hundred million tons in 2020, and the accumulated accumulation amount is about 30 hundred million tons; coal gangue is solid waste generated in the production and processing processes of coal, is a symbiotic resource of coal, and the generation amount of the coal gangue accounts for 10-25% of the coal exploitation amount, and according to statistics, the national coal yield in 2019 is 38.5 hundred million t, and the accumulated accumulation amount exceeds 50 hundred million tons; the capacity of electrolytic manganese slag in China exceeds 200 ten thousand tons, and accounts for 98 percent of the total production capacity of the electrolytic manganese in the world. The electrolytic manganese slag is the filtered acid slag generated after the metal manganese is electrolyzed, and is a key pollutant in the electrolytic manganese industry. The production of electrolytic manganese slag reaches 7-11 tons per ton of manganese, the annual production is about 2000 ten thousand tons, and the annual accumulation is more than 8000 ten thousand tons.

At present, for a large amount of solid wastes such as fly ash, coal gangue, electrolytic manganese slag, vanadium-titanium steel slag and the like, the solid wastes are mainly used for building materials and roadbed materials, and the solid wastes comprise: low-value products such as bricks and cement, and the like, but less products with high added value, such as catalysts, adsorbents and the like. The accumulation of a large amount of solid wastes such as fly ash, coal gangue, electrolytic manganese slag, vanadium-titanium steel slag and the like brings great pressure to the environmental protection work of China.

In addition, the organic volatile matters are one of the important atmospheric pollutants, have complex components and various varieties, directly influence the human health and the ecological environment, and in the treatment technology of the organic volatile matters, the catalytic combustion technology is widely applied to the purification of the organic volatile matters due to the characteristics of low energy consumption, high efficiency, no secondary pollution and the like. Aiming at the different emission characteristics and molecular structures of the organic volatile matters, the catalyst used is required to have the appropriate properties. Generally, the volatile organic compounds emitted from pharmaceutical, industrial coating, food processing and other industries are mainly low in concentration: (<700mg/m³) Large air quantity (>30000m³The characteristics determine that the volatile organic compounds have the characteristics of low diffusion efficiency, low mass transfer capacity, short contact time with a catalyst, high reaction activation energy and the like. At present, the effectiveness and the applicability of the existing commercial catalyst to the organic volatile matters are poor, and the characteristics of poor deep oxidation effect of reactants, more byproducts, high catalysis temperature and the like are mainly shown. Research shows that all enterprises adopt a combined technology of rotary wheel concentration and catalytic combustion to realize the conversion of organic volatile components from low concentration to high concentration, and then remove the low-concentration and high-air-volume organic volatile through catalytic oxidation. However, the investment and operation costs of the rotary concentrating equipment are high, and the treatment cost of the organic volatile matters is greatly increased.

Therefore, in order to improve the removal efficiency of organic pollutants and save the cost, the invention provides the catalyst suitable for the low-concentration large-air-volume organic volatile matters and the preparation method thereof.

Disclosure of Invention

Technical problem to be solved

Aiming at the defects of the prior art, the invention provides the catalyst suitable for the low-concentration large-air-volume organic volatile matter and the preparation method thereof, the utilization value of the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag solid waste can be improved by successfully preparing the catalytic material, the removal rate of the low-concentration large-air-volume organic volatile matter is improved by the prepared catalyst, the atmospheric environment is improved, the influence of accumulation of the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag solid waste on environmental protection is solved, and the utilization rate of the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag solid waste is improved.

(II) technical scheme

In order to achieve the purpose, the invention is realized by the following technical scheme: a method for preparing a catalyst suitable for low-concentration and high-air-volume organic volatile matters, which comprises the following steps:

s1, mixing the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag according to a mass ratio, adding a NaOH solution according to the mass ratio to wet the mixture, uniformly grinding the mixture, and roasting the mixture by microwave and heat radiation to obtain a roasted product;

s2, sequentially adding deionized water, tetrapropylammonium hydroxide or tetrapropylammonium bromide, ethanol and polyquaternium into the roasted product, ultrasonically heating and uniformly mixing for a certain time, and heating and stirring to obtain gel;

s3, transferring the gel in the step S2 to a reaction kettle, crystallizing by a microwave combined thermal radiation method, filtering, washing, drying and roasting to obtain the catalyst.

Preferably: in the step S1, the mass ratio of the fly ash to the electrolytic manganese slag to the vanadium-titanium steel slag is (1-10): (5-10): (4-8), mixing the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag to form mixed solid waste.

Preferably: the mass ratio of the mixed solid waste to the NaOH solution is 1 (0.5-2).

Preferably: the mass concentration of the NaOH solution is 10-40%.

Preferably: the temperature of the microwave combined heat radiation in the step S1 is 600-800 ℃, the power is 400-600W, and the roasting time in the step S1 is 1-4 hours.

Preferably: the roasted product in the step S2, deionized water, tetrapropylammonium hydroxide or tetrapropylammonium bromide, ethanol and polyquaternium, wherein the ratio of each group of the roasted product to the deionized water to the tetrapropylammonium hydroxide or tetrapropylammonium bromide to the ethanol to the polyquaternium is SiO₂Tetrapropyl hydrogen and oxygenAmmonium chloride in a molar ratio of 100 (20-30) or SiO₂The molar ratio of tetrapropylammonium bromide is 100 (20-30); SiO 2₂The mol ratio of the deionized water is 100 (2000-); ethanol: polyquaternium: SiO 2₂Mass ratio of (0.1-0.4): (0.1-0.4): 1.

preferably: the SiO₂The silicon oxide compounds in the solid waste are obtained, and when the ultrasonic heating and mixing in the step S2 are carried out, the ultrasonic power is 100-300W, the ultrasonic time is 30-60min, the heating temperature is 40-70 ℃, and the stirring speed is 400-700 r/min.

Preferably: the power of the microwave combined heat radiation in the step S3 is 400-600W, the heating temperature is 140-200 ℃, and the crystallization time is 14-24 hours, then the solid powder obtained after the washing and drying in the step S3 is roasted at 300-400 ℃ for 4-6 hours, and then at 500-700 ℃ for 5-8 hours, thus obtaining the catalyst.

Preferably: the general formula of the catalyst is Fe-Mn-V-Ti-m-MFI, wherein m-MFI is a micro mesoporous material with an MFI structure, and Fe, Mn, V and Ti are all framework atoms of m-MFI and transition metal oxide nanoclusters outside the framework.

Preferably: the catalyst has catalytic activity and stability for catalytic oxidation of oil smoke organic volatile matters, and has certain water resistance.

Preferably: the catalyst has catalytic activity and stability for catalytic oxidation of organic volatile matters of chemical raw materials.

Preferably: the fly ash can be replaced by coal gangue and slag.

The invention provides a catalyst suitable for low-concentration large-air-volume organic volatile matters and a preparation method thereof, and the catalyst has the following beneficial effects:

(1) the catalyst mainly adopts the bulk solid waste of the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag as main materials, Si and Al components do not need to be extracted, the utilization value of the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag solid waste can be improved by successfully preparing the catalytic material, the removal rate of low-concentration large-air-volume organic volatile matters is improved by the prepared catalyst, the atmospheric environment is improved, the influence of accumulation of the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag solid waste on environmental protection is avoided, and the utilization rate of the fly ash, the electrolytic manganese slag and the vanadium-titanium steel slag solid waste is improved.

(2) The mesoporous catalyst with the MFI structure is prepared by utilizing Si and Al elements in the fly ash and the electrolytic manganese slag, the mesoporous catalyst with the multi-element framework heteroatom MFI structure is prepared by utilizing Fe elements in the fly ash, Mn elements in the electrolytic manganese slag, V, Ti elements, Fe elements and the like in the vanadium-titanium steel slag, the purpose of regulating and controlling the mesoporous structure, the surface acidity and the redox performance of the catalyst based on multi-scale cooperation is realized, and the catalytic oxidation effect of low-concentration and high-air-volume organic volatile matters is further improved.

Detailed Description

Example 1

Firstly, the roasted product of the fly ash, the electrolytic manganese slag, the vanadium-titanium steel slag and NaOH, deionized water, tetrapropylammonium hydroxide or tetrapropylammonium bromide), ethanol and polyquaternary ammonium salt are ultrasonically heated and mixed according to a certain proportion, the ultrasonic power is 100-300W, the ultrasonic time is 30-60min, and the heating temperature is 40-70 ℃. In the mixture, the mol ratio of each component is SiO₂TPAOH (or TPABr) 100 (20-30), SiO₂:H₂O100 (2000-); ethanol: polyquaternium: SiO 2₂Mass ratio of (0.1-0.4): (0.1-0.4): 1, wherein SiO₂Silicon-oxygen compounds in solid waste; stirring and heating at 40-70 deg.C and stirring at 400-700r/min to obtain gel;

secondly, transferring the gel product into a reaction kettle, and crystallizing for 14-24 hours under the action of microwave combined heat radiation, wherein the microwave power is 400-.

And finally, after crystallization under the action of microwave combined heat radiation, filtering, washing and drying to obtain solid powder, roasting the solid powder for 4 to 6 hours at the temperature of 400 ℃ in the temperature range of 300 ℃ and then at the temperature of 700 ℃ in the temperature range of 500 ℃ for 5 to 8 hours to obtain the catalyst Fe-Mn-V-Ti-m-MFI.

Example 2

The catalyst which is prepared in the embodiment 1 and is suitable for low-concentration and large-air-volume organic volatile matters is subjected to mesoporous test, scanning electron microscope test and ultraviolet diffuse reflection test, and the catalyst is shown to have an obvious mesoporous structure, the absorption and desorption curve of nitrogen conforms to type IV, the hysteresis loop conforms to type H3, and the mesoporous size is 4-20 nm; the microscopic particles are nest-shaped particles formed by mutually crossing lamellae, and a large number of mesoporous structures exist among the lamellae; fe. Mn, Ti and V are all present in the form of framework atoms, and a small amount is an extra-framework oxide.

Example 3

The catalyst prepared in example 1 and suitable for low-concentration and large-air-volume organic volatile matters is used for evaluating the catalytic activity of pentanal and hexane in oil fume, the concentration of the pentanal and the hexane is 200ppm and 160ppm respectively, and the space velocity is 90000h^-1When the temperature is lower than 300 ℃, the catalytic conversion rate of the valeraldehyde and the hexane reaches more than 90 percent; in the catalytic stability experiment, the conversion rate of the organic volatile matter is maintained to be 90-95% for 100 hours at 300 ℃. The catalyst with low concentration and large air volume of organic volatile matters has good catalytic activity and stability for catalytic oxidation of oil smoke organic volatile matters, and 5-10 vol.% of H is added₂After O, the catalyst still maintains higher catalytic activity and stability, has certain water resistance and is suitable for removing organic volatile matters in high-humidity lampblack.

Example 4

The catalyst prepared by the method and suitable for low-concentration and large-air-volume organic volatile matter is used for evaluating the catalytic activity of dichloromethane, acetone and ethyl acetate in chemical raw material medicines. The concentration of dichloromethane, acetone and ethyl acetate is less than 700mg/m³The space velocity is 90000h^-1When the temperature is lower than 260 ℃, the catalytic conversion rate of dichloromethane, acetone and ethyl acetate reaches more than 92 percent; in the catalytic stability experiment, the conversion rate of the organic volatile matter is maintained to be more than 92% for 100 hours at 260 ℃. The catalyst of the low-concentration and large-air-volume organic volatile matter has good catalytic activity and stability for the catalytic oxidation of the organic volatile matter of the chemical raw material medicine.

The foregoing shows and describes the general principles, essential features, and advantages of the invention. It will be understood by those skilled in the art that the present invention is not limited to the embodiments described above, and the preferred embodiments of the present invention are described in the above embodiments and the description, and are not intended to limit the present invention. The scope of the invention is defined by the appended claims and equivalents thereof.