阅读说明：本技术 一种耐湿的臭氧去除催化剂的制备方法及应用 (Preparation method and application of moisture-proof ozone removal catalyst ) 是由 周莹 黎邦鑫 张骞 肖杰 李恩智 王芳 于姗 于 2019-09-25 设计创作，主要内容包括：本发明公开了一种耐湿的臭氧去除催化剂的制备方法及应用。本发明以可溶性镍盐(NiCl<Sub>2</Sub>、Ni(NO<Sub>3</Sub>)<Sub>2</Sub>、Ni(Ac)<Sub>2</Sub>)、沉淀剂(乙二胺、氨水、尿素)为前驱体,采用水热法合成混合镍盐臭氧去除材料,并以高浓度(ppm级)、高湿度(80％)的臭氧分析装置对该材料进行活性评价。经具体实例结果表明,在常温环境中,该材料对臭氧的去除率高达98％,同时实现了湿润环境中的稳定性能,解决了传统催化材料在去除臭氧时无法应对高湿度环境的问题。该发明：第一,相对于传统MnO<Sub>2</Sub>材料,混合镍盐制备过程中不涉及剧烈的反应过程；第二,相比于活性炭,纳米的混合镍盐能够在高浓度、高温的环境中稳定存在；第三,可应用在空气净化、尾气净化领域,尤其是在高湿度环境下去除臭氧等方面具有广阔的应用前景。(The invention discloses a preparation method and application of a moisture-proof ozone removal catalyst. The invention uses soluble nickel salt (NiCl) 2 、Ni(NO 3 ) 2 、Ni(Ac) 2 ) And a precipitator (ethylenediamine, ammonia water and urea) is used as a precursor, a mixed nickel salt ozone removing material is synthesized by a hydrothermal method, and the material is subjected to activity evaluation by an ozone analysis device with high concentration (ppm level) and high humidity (80%). The specific example results show that the material has the ozone removal rate of 98% in a normal-temperature environment, realizes the stability in a humid environment, and solves the problem that the traditional catalytic material cannot cope with a high-humidity environment when removing ozone. The invention comprises the following steps: first, with respect to conventional MnO 2 the material does not relate to a violent reaction process in the preparation process of the mixed nickel salt; second, compareIn the activated carbon, the nano mixed nickel salt can stably exist in a high-concentration and high-temperature environment; and thirdly, the method can be applied to the fields of air purification and tail gas purification, and particularly has wide application prospect in the aspects of removing ozone and the like in a high-humidity environment.)

1. A preparation method of a moisture-resistant ozone removal catalyst is characterized by comprising the following steps:

(1) selection of precursor concentration: preparing a mixed solution of soluble nickel salt and a precipitator with a certain concentration;

(2) temperature, time of thermal reaction: and putting the precursor liquid into a reaction kettle, and carrying out thermal reaction under the constant temperature condition.

2. The method of claim 1, wherein the moisture-resistant ozone removal catalyst is prepared by:

The nickel salt in the step (1) comprises NiCl₂、Ni(NO₃)₂、Ni(Ac)₂The precipitator comprises one or more of ethylenediamine, ammonia water and urea;

The concentration of the nickel ions in the step (1) is 0.1-0.5 mol/L, and the total concentration of the precipitant is 0.2-1 mol/L;

the temperature of the thermal reaction in the step (2) is 60-100 ℃, and the reaction time is 6-8 h.

3. a moisture-resistant ozone-removing catalyst material is obtained by the preparation method of any one of claims 1-2, and the obtained catalyst is a flaky and microspherical mixed nickel salt catalyst.

4. The moisture-proof ozone removal catalyst is applied to removal of high-humidity ozone, and is characterized in that: the removing device mainly comprises a laboratory self-built stable gas circuit system and a high-precision ozone detector, the humidity and the ozone concentration change are monitored in real time, and the catalytic activity of the material is evaluated mainly by the removal rate of the tail gas containing ozone with the relative humidity of about 80% and the stabilization time of the catalytic effect.

5. the moisture-resistant ozone-removing catalyst evaluation method according to claim 4, wherein:

the volume of the reactor in the step (2) is 100-200 mL;

The mass of the catalyst in the step (2) is 100-200 mg, and the carrier is melamine sponge;

The wetting air flow rate in the step (2) is 0.5-2L/min, and the relative humidity is 80 +/-5%;

the concentration of the ozone obtained by the ultraviolet generating device in the step (2) is 20-100 ppm.

6. The method for efficiently and stably catalyzing and removing the humid ozone according to claim 5 is mainly used in the field of air and tail gas purification, and has wide market prospect and application value, such as: the ozone removing material is installed at a position of an air conditioner, a wall, a core part of an air purifier, etc., is installed at an end of industrial exhaust gas, etc.

Technical Field

The invention relates to the field of air purification, in particular to a hydrothermal preparation method and application of a moisture-resistant mixed nickel salt ozone removing material.

background

With the release of 'blue sky plan' in China, environmental air pollution control is on schedule, wherein ozone becomes the primary pollutant in many places in China, and is a strong oxidizing gas which has great harm to the respiratory system and is easy to cause acute damage to the lung. Meanwhile, the strong oxidizing property of ozone can also act on metal materials and partial non-metal materials, so that industrial economic loss is caused, and the ozone is a difficult problem to be solved urgently nowadays.

the most common in the existing ozone removal technology is activated carbon and composite materials thereof (CN2780295, CN109364686A), but the carbon material used in the technology is oxidized in the environment of ozone with higher concentration, and the performance loss occurs; the other technology is that a catalyst is loaded on an inert substrate, which is a green and environment-friendly technology with important application prospect in the fields of energy and environment, the reaction rate of the spontaneous process of the decomposition of ozone is accelerated by reducing the activation energy generated by the reaction, and the prior related patents are focused on manganese-based compounds (CN109012735A and CN109569643A), iron-based catalysts (CN103272612A) and the like.

however, most manganese and iron-based catalysts have poor moisture resistance and poor stability, and high energy consumption calcination and hydrothermal processes are needed in the synthesis process; the noble metal catalyst with excellent performance has the problem of cost, and in order to solve the problem, the invention develops a catalyst which is efficient and stable in a high-humidity environment.

Disclosure of Invention

the purpose of the invention is as follows: providing a preparation method of an ozone removal catalytic material capable of adapting to a high-humidity environment; the problem of catalyst material performance stability low when getting rid of high humidity ozone is solved to provide an economic, environmental protection, practical catalytic material for different environmental air purification. The nickel-based material has better cycle performance and proper oxidation-reduction potential (DOI:10.1142/S1793292019500449) in electrochemistry, and the nickel-based catalytic material is applied to ozone removal after the shape and size of the nickel-based catalytic material are adjusted, so that the mixed nickel salt catalyst capable of working in a humid environment is obtained.

the purpose of the invention is realized by the following technical scheme: preparation of a nickel salt ozone removal catalyst comprising the steps of:

(1) Preparing a precursor: preparing nickel salt and precipitant solution with certain concentration, slowly mixing under sealed and stirred conditions, and continuously stirring until a precursor is obtained.

(2) Thermal synthesis: and (2) placing the precursor in the step (1) under a constant temperature condition for reacting for a certain time, and finally carrying out suction filtration, washing and drying on the liquid cooled to room temperature to obtain catalyst powder.

The nickel salt solution in the step (1) contains NiCl₂、Ni(NO₃)₂、Ni(Ac)₂one or more of the nickel ions are mixed according to a certain proportion, and the concentration of the nickel ions is 0.1-0.5 mol/L in total;

The precipitator in the step (1) comprises one or more of ethylenediamine, ammonia water and urea, and the concentration of the solution is 0.2-1 mol/L;

The reaction temperature in the step (2) is 60-100 ℃, and the reaction time is 6-8 h;

The drying temperature in the step (2) is 40-80 ℃.

The invention obtains a nickel salt catalyst mixed by flake and micro-sphere, and has high catalytic performance and moisture resistance.

The purpose of the invention is realized by the following technical scheme: a preparation method and application of a moisture-proof ozone removal catalyst. Its remove device mainly includes that the laboratory builds stable gas circuit system and high accuracy ozone detector by oneself, and real-time supervision humidity, ozone concentration change mainly use relative humidity to be 80 +/-5%'s ozone tail gas's clearance and catalytic effect stability time to evaluate the catalytic activity of material, mainly contain following step:

(1) the ozone catalytic material is loaded on a carrier through impregnation and is arranged in a catalytic reactor;

(2) After passing through an ultraviolet ozone generating device, wet air with a certain flow rate is introduced into a reactor;

(3) starting an ultraviolet ozone generating device, detecting the concentration of ozone in the tail gas, and comparing the concentration with the data of the catalyst which is not put in;

The mass of the catalyst in the step (1) is 100-200 mg, the carrier is melamine sponge, and the volume of the reactor is 500 mL;

The wetting air flow rate in the step (2) is 0.5-2L/min, the relative humidity is 80 +/-5%, and the ozone concentration is 40-50 ppm;

the method for efficiently and stably catalyzing and removing the humid ozone is mainly used in the field of air and tail gas purification, and has wide market prospect and application value. For example: the ozone removing material is installed at a position of an air conditioner, a wall, a core part of an air purifier, etc., is installed at an end of industrial exhaust gas, etc.

Compared with the prior art, the invention has the following advantages and effects:

Firstly, a non-activated carbon material is used as a catalyst, so that the ozone oxidation loss of the catalyst is avoided; secondly, compared with the common MnO, the mixed nickel salt ozone catalytic material synthesized by the invention₂The catalyst prepared by the method does not use a strong oxidant potassium permanganate, does not have strong redox reaction, and has a simpler preparation process; thirdly, the catalytic performance of the catalyst is stable, and the removal rate of more than 98 percent is kept for 12 hours under the condition of high-concentration ozone; fourth, the catalyst can be operated in a high humidity environment without significant degradation of its performance.

drawings

FIG. 1 is an X-ray diffraction pattern of a mixed nickel salt ozone removing material prepared according to an embodiment of the present invention;

FIG. 2 is a fluorescence spectrum of a mixed nickel salt ozone removing material prepared according to an embodiment of the present invention;

FIG. 3 is a scanning electron microscope image of a mixed nickel salt ozone removing material prepared according to an embodiment of the present invention;

FIG. 4 is a graph showing the performance of the mixed nickel salt ozone removing material prepared according to the embodiment of the present invention, wherein the concentration of ozone is 40 ppm.

Detailed description of the preferred embodiment

the invention is described in further detail below with reference to specific embodiments and the attached drawings, but the embodiments of the invention are not limited to:

preparing a mixed nickel salt ozone removing material:

(1) preparing a catalyst precursor: firstly, weighing 10g of nickel chloride, 20g of nickel nitrate and 30g of urea, mixing and dissolving in 1L of deionized water, and stirring for 30 min.

(2) Thermal synthesis of mixed nickel salt ozone removal material: and (2) putting the precursor prepared in the step (1) into a reaction kettle, and then putting the reaction kettle into an oven at 80 ℃ for heat preservation for 8 hours. Finally, the material cooled to room temperature was washed alternately with deionized water and absolute ethanol and then dried in a drying oven at 40 ℃.

the phase and the property of the mixed nickel salt ozone removing material are tested:

FIG. 1 is an XRD pattern of a mixed nickel salt ozone removing material, the material is an approximately amorphous substance and has diffraction peaks at certain angles, and an analysis result shows that the material is a mixture of two nickel salts.

FIG. 2 is a fluorescence spectrum of the mixed nickel salt ozone removing material, which can be analyzed to obtain a mixed nickel salt ozone removing material with a certain content of each component.

FIG. 3 is an SEM image of a mixed nickel salt ozone removing material, which has two mixed shapes of nano-sheet and micro-sphere,

Application of the mixed nickel salt ozone removal material:

(1) The 100mg mixed nickel salt ozone removing material of the invention is impregnated and loaded by 20cm³Drying the sponge at 50 ℃, and then putting the sponge into a reactor;

(2) and continuously introducing ozone and humid air into the reaction system, switching the contact between the ozone and the mixed nickel salt ozone removing material when the ozone concentration is 39ppm, and simultaneously starting to record data.

FIG. 4 is a test result of the mixed nickel salt ozone removing material for removing ozone: the removal rate of ozone was 99.7%, and a stable catalytic activity for a long time was achieved.

The mixed nickel salt ozone removing material provided by the invention has a good ozone removing effect at normal temperature, can remove high-concentration ozone, simultaneously keeps activity, and overcomes the inactivation phenomenon caused by water vapor adsorption when the traditional catalyst and adsorbent are used for removing high-humidity ozone.