CN-121988343-A - CuMn (CuMn)2O4/γ-Al2O3Catalyst, preparation method and application thereof

Abstract

The invention relates to the technical field of wastewater treatment, in particular to a CuMn 2 O 4 /γ-Al 2 O 3 catalyst, a preparation method and application thereof. The CuMn 2 O 4 /γ-Al 2 O 3 catalyst consists of carrier gamma-Al 2 O 3 pellets and an active component CuMn 2 O 4 . The CuMn 2 O 4 /γ-Al 2 O 3 catalyst is applied to an ozone-hydrogen peroxide synergistic catalytic oxidation system for treating organic wastewater, and the activation capability of the surface to ozone and hydrogen peroxide is optimized by utilizing oxygen vacancies and cation migration characteristics existing between Cu and Mn sites, so that the degradation efficiency of organic matters is improved. The system not only solves the problems of low heterogeneous catalytic oxidation efficiency and poor catalyst stability in the prior art, but also remarkably improves COD removal efficiency and keeps good circulation stability, and realizes high-efficiency degradation of high-concentration organic pesticide wastewater and recycling of the catalyst.

Inventors

• ZHANG HUIYING
• LI JINGYU
• DENG GUOHUI
• LI JING
• LI ZEQUAN
• MAO JIN
• DAI QILIANG
• Fu Linie

Assignees

• 云南农业大学

Dates

Publication Date

20260508

Application Date

20260227

Claims (9)

1. 1. The CuMn 2 O 4 /γ-Al 2 O 3 catalyst is characterized by comprising a carrier and an active component, wherein the carrier is gamma-Al 2 O 3 pellets, the active component is tetragonal spinel phase CuMn 2 O 4 , and the CuMn 2 O 4 is loaded on the carrier; Wherein the molar ratio of Cu to Mn is 1:2.
2. 2. The CuMn 2 O 4 /γ-Al 2 O 3 catalyst according to claim 1, wherein the mass percentage of Mn element in the CuMn 2 O 4 /γ-Al 2 O 3 catalyst is 3.0wt% to 4.5wt% and the mass percentage of Cu element is 1.5wt% to 2.5wt%.
3. 3. A method of preparing the CuMn 2 O 4 /γ-Al 2 O 3 catalyst of claim 1, comprising the steps of: using citric acid as a complexing agent, and dissolving soluble copper salt, soluble manganese salt and citric acid in water together to obtain an impregnating solution; Soaking gamma-Al 2 O 3 pellets in the impregnating solution, taking out and drying, and performing three-stage gradient calcination treatment to obtain a CuMn 2 O 4 /γ-Al 2 O 3 catalyst; Wherein, in the impregnating solution, the mol ratio of Cu 2+ to Mn 2+ is 1:2.
4. 4. The method according to claim 3, wherein the mass ratio of the total mass of the soluble copper salt and the soluble manganese salt to the citric acid is 3.5 to 4:1.
5. 5. The method according to claim 3, wherein the three-stage gradient calcination is performed in an air atmosphere by heating to 150-200 ℃ and calcining at 150-200 ℃ for 1.5 hours, heating to 450-550 ℃ and calcining at 450-550 ℃ for 1.5 hours, heating to 750-800 ℃ and calcining at 750-800 ℃ for 4 hours.
6. 6. The preparation method according to claim 3, wherein the gamma-Al 2 O 3 pellets are further subjected to pretreatment, wherein the pretreatment method comprises the steps of sequentially cleaning, drying and roasting the gamma-Al 2 O 3 pellets to remove moisture and organic impurities in the gamma-Al 2 O 3 pellets; wherein the condition of the roasting treatment is that the roasting is carried out for 4 hours at 450-550 ℃.
7. 7. Use of a CuMn 2 O 4 /γ-Al 2 O 3 catalyst as claimed in claim 1 for the catalytic oxidation treatment of organic waste water.
8. 8. The use according to claim 7, wherein the catalyst is used in combination with O 3 and H 2 O 2 for catalytic oxidative degradation of organic wastewater by means of CuMn 2 O 4 /γ-Al 2 O 3 as catalyst, comprising: Adding the CuMn 2 O 4 /γ-Al 2 O 3 catalyst into the organic wastewater, adjusting the initial pH value of the organic wastewater to 7.5-11.5, introducing ozone and hydrogen peroxide, and performing catalytic oxidation reaction at normal temperature and normal pressure.
9. 9. The use according to claim 8, wherein the mass to volume ratio of the CuMn 2 O 4 /γ-Al 2 O 3 catalyst to the organic wastewater is 60 g-100 g:400ml, and the mass concentration of the organic in the organic wastewater is 500 mg/L-1000 mg/L.

Description

CuMn 2O4/γ-Al2O3 catalyst and preparation method and application thereof Technical Field The invention relates to the technical field of wastewater treatment, in particular to a CuMn 2O4/γ-Al2O3 catalyst, a preparation method and application thereof. Background Along with the development of modern agriculture on the plateau to scale and intensification, the pesticide is obviously increased for preventing and controlling plant diseases and insect pests and improving crop yield. However, excessive dependence on pesticides is common in agricultural production, and part of producers lack of environmental protection consciousness, a large amount of organic wastewater is generated in links such as pesticide application, instrument cleaning, rainfall runoff and the like, and particularly under the sudden conditions such as strong heavy rain, package damage or improper dumping, high-concentration wastewater is mixed into farmland to be dewatered, so that the agricultural production has the characteristics of high concentration of organic pollutants, high toxicity, difficult biodegradation, complex components and poor biodegradability. If untreated, the water is directly discharged into the surrounding water body, which is easy to cause serious harm to the ecological environment and the human health. Although the efficient organophosphorus pesticides represented by trichlorfon are widely applied to agricultural production, the residues in the environment and the production wastewater have the characteristics of high phosphorus, high salt and difficult degradation. More serious, the compound can be rapidly converted into dichlorvos with stronger toxicity under the weak alkaline condition, so that the requirement for rapid and efficient treatment of the compound is urgent. At present, ecological engineering measures mainly used for natural purification such as ecological ditches, artificial wetlands, stabilization ponds and the like are mainly adopted for low-concentration farmland water withdrawal under normal conditions. The method has the advantages of low cost and simple operation and maintenance, but has poor adaptability to sudden and high-concentration pesticide pollution impact load, limited treatment efficiency and difficult effective application to high-risk wastewater generated by first runoff or leakage accidents after the application. In addition, although the conventional physicochemical treatment method (such as adsorption and coagulation) can be used as a strengthening means, the problems of difficult regeneration of the adsorbent, poor removal effect on the soluble micromolecular pesticide, and secondary pollution such as large-scale chemical sludge are caused. Disclosure of Invention Aiming at the defects existing in the prior art, the invention provides a CuMn 2O4/γ-Al2O3 catalyst, a preparation method and application thereof, wherein the CuMn 2O4/γ-Al2O3 catalyst consists of a carrier gamma-Al 2O3 pellet and an active component tetragonal spinel phase CuMn 2O4 loaded on the carrier, and has a porous fluffy reticular structure and mesoporous characteristics. The CuMn 2O4/γ-Al2O3 catalyst is applied to an ozone-hydrogen peroxide (O 3-H2O2) synergistic catalytic oxidation system for treating organic wastewater, and the activation capacity of the surface to ozone and hydrogen peroxide is optimized by utilizing oxygen vacancies and cation migration characteristics existing between Cu and Mn sites, so that the degradation efficiency of organic matters is improved. The system not only solves the problems of low heterogeneous catalytic oxidation efficiency and poor catalyst stability in the prior art, but also remarkably improves COD removal efficiency and keeps good circulation stability, and realizes high-efficiency degradation of high-concentration organic pesticide wastewater and recycling of the catalyst. In order to achieve the above purpose, the technical scheme adopted by the invention is as follows: The first object of the invention is to provide a CuMn 2O4/γ-Al2O3 catalyst, which consists of a carrier and an active component, wherein the carrier is gamma-Al 2O3 pellets, the active component is tetragonal spinel phase CuMn 2O4, and the CuMn 2O4 is loaded on the carrier, and the molar ratio of Cu to Mn is 1:2. The present invention aims to form tetragonal spinel phases CuMn 2O4 with high catalytic activity. The molar ratio of Cu to Mn is set to 1:2 in order to produce as much tetragonal spinel phase CuMn 2O4 as possible in the calcined product. Because the spinel has a structural general formula of AB 2O4, the ideal cation molar ratio is that the A site (Cu) and the B site (Mn) are 1:2. The spinel structure enables Cu and Mn to be orderly arranged according to a molar ratio of 1:2, a crystal framework with good thermal stability is formed, and active components are ensured not to be lost easily in the reaction. Preferably, in the CuMn 2O4/γ-Al2O3 catalyst, the mass percentage of Mn element is 3.0-4