CN-122006787-A - Fly ash-based zeolite ozone oxidation catalyst and preparation method and application thereof

Abstract

The invention discloses a fly ash-based zeolite ozone oxidation catalyst and a preparation method and application thereof, wherein the preparation method comprises the steps of carrying out acid washing pretreatment on fly ash; synthesizing the fly ash zeolite by a melt hydrothermal method to obtain the fly ash-based zeolite ozone oxidation catalyst. The method has the remarkable effects that the scheme synthesizes the fly ash-based zeolite catalyst taking the self transition metal Fe element as an active center by adopting acid washing pretreatment and a molten hydrothermal method, directly utilizes Si and Al elements in the fly ash to construct a zeolite framework structure as a catalyst carrier, can realize the efficient ozone oxidation degradation of atrazine by taking the self-contained Fe element as the active center of the catalyst under the condition of not adding a transition metal source additionally, and can not cause secondary pollution.

Inventors

• WANG XI
• LIU YAN
• XU ZIHE
• LU ZIXIN
• ZHANG LONGWEI

Assignees

• 华南师范大学

Dates

Publication Date

20260512

Application Date

20260303

Claims (10)

1. 1. The preparation method of the fly ash-based zeolite ozone oxidation catalyst is characterized by comprising the following steps: Step 1, carrying out acid washing pretreatment on fly ash; and 2, synthesizing the fly ash zeolite by a fused hydrothermal method to obtain the fly ash-based zeolite ozone oxidation catalyst.
2. 2. The preparation method of the fly ash-based zeolite ozonation catalyst according to claim 1, wherein the step of pickling the fly ash in the step 1 comprises the following steps: Step 1.1, preparing hydrochloric acid solution; And 1.2, weighing a certain amount of fly ash, mixing with a certain volume of hydrochloric acid solution, stirring for reaction, washing, drying and grinding to obtain the pretreated fly ash.
3. 3. The method for preparing a catalyst for ozone oxidation of fly ash based zeolite according to claim 2, wherein in step 1.1, the volume fraction of the hydrochloric acid solution is 10%.
4. 4. The preparation method of the coal ash-based zeolite ozonation catalyst according to claim 2, wherein in the step 1.2, the mass-volume ratio of coal ash to hydrochloric acid solution is 1:5g/mL, and the temperature of stirring reaction is 65-105 ℃.
5. 5. The method for preparing the catalyst for the ozone oxidation of the fly ash based zeolite according to claim 1, wherein the step of preparing the fly ash zeolite by a fused hydrothermal method in the step 2 comprises the following steps: Step 2.1, weighing the pretreated fly ash, mixing with sodium hydroxide particles, fully grinding for a period of time, and then placing in a muffle furnace for calcination; step 2.2, fully grinding and calcining the obtained mixture, adding a certain amount of deionized water, and stirring at room temperature; and 2.3, transferring the mixture obtained after full stirring into a polytetrafluoroethylene reaction kettle liner for hydrothermal reaction, washing, drying and grinding to obtain the fly ash zeolite.
6. 6. The method for preparing a fly ash-based zeolite ozonation catalyst according to claim 5, wherein in the step 2.1, the mass ratio of the pretreated fly ash to the sodium hydroxide particles is 10: (8-14), the calcination temperature is 450-650 ℃, the calcination time is 1-3 h, and the temperature-raising program is 1 ℃ per minute.
7. 7. The method for preparing the fly ash-based zeolite ozonation catalyst according to claim 5, wherein the stirring time in the step 2.2 is 20-30 hours.
8. 8. The method for preparing a fly ash-based zeolite ozonation catalyst according to claim 5, wherein in the step 2.3, the hydrothermal reaction temperature is 80-100 ℃ and the reaction time is 10-14 h.
9. 9. A catalyst for ozone oxidation of fly ash based zeolite, which is prepared by the method according to any one of claims 1 to 8.
10. 10. Use of a fly ash-based zeolite ozonation catalyst prepared by the method of any one of claims 1-8 for degrading atrazine.

Description

Fly ash-based zeolite ozone oxidation catalyst and preparation method and application thereof Technical Field The invention relates to the technical field of catalytic degradation, in particular to a fly ash-based zeolite ozone oxidation catalyst, a preparation method and application thereof. Background Atrazine, also known as Atrazine (ATZ), is a triazine herbicide, widely applied to weed control of crops, and has the characteristics of simple production and manufacture, low cost, good control effect and the like, and the use amount rises year by year. However, ATZ has the characteristics of high chemical stability, strong environmental persistence and the like, and is easy to diffuse into aquatic ecosystems such as groundwater, surface water and the like, so that the pollution problem of the groundwater, rivers and lakes is increasingly serious. The environmental residues of ATZ pose a serious hazard to plant, animal and human health. For plants, ATZ not only inhibits the growth of target weeds, but also produces toxic effects on non-target crops, which cause the growth to be blocked or even dead, and destroy the diversity of farmland ecosystems. ATZ also has obvious endocrine disrupting effect, and can affect the development of the reproductive system of fish and amphibian aquatic organisms, resulting in unbalanced sex ratio, reduced reproductive capacity and even reduced population quantity. In addition, ATZ poses a hazard to mammals and humans mainly through drinking water and food chain exposure, and long-term exposure to low concentrations of ATZ can lead to disorders of the endocrine system, as well as interfering with normal secretion of hormones, thereby causing reproductive health problems. In conclusion, the wide application of ATZ in agricultural production not only exacerbates the pollution problem of water environment in China, but also forms a serious threat to the ecological system and human health. Therefore, the search for efficient water treatment technologies to cope with ATZ pollution has become an important research direction in the current environmental field. Currently, ATZ treatment processes mainly include physical, biological and chemical processes. The physical treatment technology of ATZ mainly comprises an adsorption method and a membrane separation method, wherein the adsorption method or the membrane separation method only separates ATZ by physical action, so that degradation of ATZ can not be realized, and secondary pollution risk exists. Biological treatment technology is to remove organic pollutants in water by utilizing the metabolism of microorganisms, and has certain limitation in practical application. First, microorganisms have selectivity and specificity for degradation of pollutants, and are difficult to adapt to actual agricultural polluted water bodies with complex components and high toxicity. Secondly, the biological method has slower treatment speed and longer period, and limits the application of the biological method in practical engineering. Chemical methods encompass a variety of techniques such as redox, chemical precipitation, and ion exchange. Among them, advanced oxidation techniques (AOPs) are widely used in the treatment of ATZ due to their ability to efficiently degrade difficult-to-treat pollutants, and AOPs decompose pollutants in the environment mainly by generating Reactive Oxygen Species (ROS), such as hydroxyl radicals (OH) and superoxide radicals (O 2-), etc. Wherein, the Fenton oxidation method, the ozone oxidation method, the photocatalytic oxidation method and the like can effectively remove the atrazine. The ozone oxidation technology can be further divided into homogeneous catalytic ozone oxidation and heterogeneous catalytic ozone oxidation, wherein the heterogeneous ozone oxidation method is the technical method adopted by the invention, has the advantages of high O 3 utilization rate, wide pH application range, easy separation of a solid catalyst from water phase, low catalyst loss and low risk of secondary pollution, can effectively overcome the limitations of a physical method and a biological method, and is a degradation method of ATZ in water with great prospect. Fly ash is industrial solid waste generated by coal combustion, contains various heavy metal elements and can cause harm to the environment and human health. Along with the annual increase of thermal power installation, the fly ash becomes one of the main solid wastes in China. The comprehensive utilization rate of the fly ash in China is about 80%, most of the unused fly ash is piled up, so that serious land occupation is caused, and environmental pollution is easy to cause. Because the fly ash contains a large amount of Si and Al elements, the fly ash can be used for synthesizing zeolite, and the synthesized zeolite has unique structure and performance and can be widely applied to the environmental fields of VOCs removal, CO 2 adsorption, NO x removal, wastewater treatm