CN-121988601-A - Method for restoring imidacloprid pesticide polluted soil based on mechanochemistry

Abstract

The invention discloses a method for repairing imidacloprid pesticide contaminated soil based on mechanochemistry, which uses potassium ferrate and calcium oxide as ball milling reagents to ball mill the imidacloprid pesticide contaminated soil. According to the method for repairing the imidacloprid pesticide contaminated soil based on mechanochemistry, potassium ferrate is used as a main grinding agent, calcium oxide is used as a grinding aid, the ball milling mechanical force effect is utilized to induce calcium oxide to generate oxygen vacancies and free electrons, the generated free electrons activate the potassium ferrate, so that more high-activity species are released by the potassium ferrate, imidacloprid molecules can be jointly attacked under the synergistic effect of the active species and the free electrons, and the imidacloprid molecular structure is damaged and decomposed, thereby the effective repair of the imidacloprid pesticide contaminated soil can be realized, the repair effect of the imidacloprid pesticide contaminated soil is up to 96%, and the method has the advantages of low cost, good repair effect, environmental friendliness and the like, and meanwhile, the method has the advantages of lower energy consumption, high use value and good application prospect under the same repair effect.

Inventors

• PENG WEI
• YANG QI
• LUO KUN

Assignees

• 湖南大学

Dates

Publication Date

20260508

Application Date

20260325

Claims (10)

1. 1. A method for repairing imidacloprid pesticide contaminated soil based on mechanochemistry is characterized in that potassium ferrate and calcium oxide are used as ball milling reagents, and ball milling is carried out on the imidacloprid pesticide contaminated soil.
2. 2. The method of claim 1, wherein the mass ratio of the ball milling reagent to the imidacloprid pesticide contaminated soil is 0.5-2:10.
3. 3. The method of claim 2, wherein the mass ratio of potassium ferrate to calcium oxide is 1-9:1.
4. 4. The method according to any one of claims 1 to 3, wherein the method is to ball-mill imidacloprid pesticide contaminated soil with potassium ferrate and calcium oxide as ball-milling reagents, and comprises the following steps: (1) Adding imidacloprid pesticide polluted soil and a ball milling reagent into a ball milling tank, and adding grinding balls; (2) And symmetrically placing the ball milling tanks into a horizontal planetary ball mill for ball milling, and finishing the restoration of the imidacloprid pesticide polluted soil.
5. 5. The method of claim 4, wherein in the step (1), the mass ratio of the grinding balls to the imidacloprid pesticide contaminated soil is 5-25:1.
6. 6. The method of claim 5, wherein in step (1), the grinding balls are zirconia balls, and the diameter of the grinding balls is 8mm.
7. 7. The method according to claim 5, wherein in the step (1), the concentration of imidacloprid in the imidacloprid pesticide contaminated soil is 16 mg/kg or less.
8. 8. The method according to claim 7, wherein in the step (1), the imidacloprid pesticide contaminated soil further comprises the steps of air-drying the imidacloprid pesticide contaminated soil, sieving with a 10-mesh sieve, grinding, and sieving with a 60-mesh sieve to obtain imidacloprid pesticide contaminated soil powder.
9. 9. The method according to claim 4, wherein in the step (2), the rotation speed of the ball mill is 400rpm to 600rpm.
10. 10. The method according to claim 9, wherein in the step (2), the ball milling is performed continuously after the ball milling is performed for 1min every 5min, and the rotation direction is changed, wherein the ball milling time is less than or equal to 4h.

Description

Method for restoring imidacloprid pesticide polluted soil based on mechanochemistry Technical Field The invention belongs to the technical field of soil pollution remediation, and relates to a method for remedying imidacloprid pesticide polluted soil based on mechanochemistry. Background Imidacloprid (IMI) is a neonicotinoid insecticide widely used in the agricultural field for decades to control insect pests. It exhibits insecticidal activity primarily by blocking normal conduction through the insect central nervous system. However, in recent years, imidacloprid has been reported to be an emerging contaminant worldwide due to its large-scale use, with different toxic effects on a range of non-target organisms including humans. Therefore, the removal of imidacloprid from the soil ecosystem has attracted considerable attention. Currently, methods for eliminating imidacloprid in the environment generally include physicochemical (oxidation, adsorption, hydrolysis, light irradiation, etc.) and biodegradation. Biodegradation is usually carried out by means of microorganisms capable of degrading imidacloprid, including bacillus, pseudomonas, mycobacterium, rhizobium, rhodococcus and stenotrophomonas, and has the advantages of environmental protection and no secondary pollution, but the biodegradation has severe requirements on environmental conditions such as temperature, pH, carbon source and the like and has long repair time on imidacloprid polluted soil. The physicochemical method usually uses one or more combination methods of physical methods such as adsorption and chemical methods such as oxidation reduction and hydrolysis, and has the advantages of high-efficiency degradation, rapid reaction, wide application range and the like, but part of chemical oxidants are expensive and cause secondary pollution to soil. Therefore, the method for searching the material which is low in cost and does not pollute the soil has important practical significance for repairing the imidacloprid pesticide polluted soil. In recent years, mechanochemical methods are increasingly receiving attention in the field of restoring POPs contaminated soil due to the simple operation process and high restoration efficiency. The mechanochemical method is an ectopic repair technology, which does not depend on a solvent system, mixes the polluted soil and the additive according to a certain proportion, uses a high-energy ball mill for grinding, and is an efficient green environment-friendly repair method. However, in the existing repairing method based on mechanochemical method, the adopted additives, such as persulfate or potassium permanganate, are difficult to destroy the molecular structure of the imidacloprid, have poor effect of degrading the imidacloprid, are difficult to realize effective repairing of the imidacloprid pesticide polluted soil, and meanwhile, have higher toxicological characteristics or have toxic action on decomposed products, so that secondary pollution is caused to the soil. Therefore, the method for restoring the imidacloprid pesticide polluted soil has the advantages of low cost, good restoration effect and environmental protection. Disclosure of Invention The invention aims to solve the technical problem of overcoming the defects of the prior art and providing a method for restoring imidacloprid pesticide polluted soil based on mechanochemistry, which has the advantages of low cost, good restoration effect and environmental protection. In order to solve the technical problems, the invention adopts the following technical scheme: A method for repairing imidacloprid pesticide contaminated soil based on mechanochemistry comprises the step of ball milling imidacloprid pesticide contaminated soil by taking potassium ferrate and calcium oxide as ball milling reagents. According to the method, the mass ratio of the ball milling reagent to the imidacloprid pesticide polluted soil is 0.5-2:10. According to the method, the mass ratio of the potassium ferrate to the calcium oxide is 1-9:1. The method is further improved, the method is to ball-mill the imidacloprid pesticide polluted soil by taking potassium ferrate and calcium oxide as ball-milling reagents, and comprises the following steps: (1) Adding imidacloprid pesticide polluted soil and a ball milling reagent into a ball milling tank, and adding grinding balls; (2) And symmetrically placing the ball milling tanks into a horizontal planetary ball mill for ball milling, and finishing the restoration of the imidacloprid pesticide polluted soil. In the method, the mass ratio of the grinding balls to the imidacloprid pesticide polluted soil in the step (1) is 5-25:1. In the method, in the step (1), the grinding balls are zirconia balls, and the diameter of the grinding balls is 8mm. In the method, the concentration of the imidacloprid in the imidacloprid pesticide polluted soil in the step (1) is less than or equal to 16 mg/kg. In the step (1), the imidacloprid pesticide