Chemical modulatory agent for harnessing soil pollution and its preparing method

Abstract

A chemical regulator for controlling soil pollution and a preparation method thereof. A substance that can strongly complex copper and zinc and is used to treat soil polluted by heavy metals. The chemical regulating agent of the present invention is a large water-soluble chitosan substance with a molecular weight lower than 2000. Its preparation method: take polymer chitosan and add distilled water 10 to 20 times its weight and 30% H 2 o 2 , to make the concentration reach 2-5 (% by weight), stir until fully swollen; place in a microwave oven for 2-5 minutes on high heat and take it out from the microwave oven after standing for 5-10 minutes; add distilled water to make it return to the original Then place it in an ultrasonic cleaning machine for intermittent ultrasonication for no less than 5 hours; filter with a Buchner funnel and dilute 1-50 times with water in the transparent solution obtained by filtering to be the liquid chemical regulator of the present invention . It is non-toxic, biodegradable and can be directly used for leaching treatment of heavy metal-contaminated soil or repairing polluted soil with plant extraction.

Description

technical field [0001] The invention relates to a substance for controlling soil pollution and a preparation method thereof, in particular to a chemical regulator capable of strongly complexing heavy metals copper and zinc and being used for leaching treatment or phytoremediation of heavy metal polluted soil. Background technique [0002] As we all know, heavy metals are pollutants that will continue to accumulate and remain. Due to metal mining, smelting, and sewage irrigation, the area of ​​soil polluted by heavy metals is constantly expanding; therefore, the restoration and improvement of polluted soil has become It has become a major scientific issue in our country and even in the world. [0003] At present, the soil treatment methods polluted by heavy metals can be classified into two categories: one is to stabilize the heavy metals in the soil to reduce its activity in the soil, and its related patents, such as the Chinese patent 02125605. Heavy metal chelating agent ...

AI Technical Summary

Problems solved by technology

The disadvantage of the former is that there is still a potential threat in the treated soil, because the total amount of heavy metals it contains has not been reduced, so its activity may still be released under certain conditions, and these conditions have yet to be determined. However, these methods are not reliable because they are limited to research; the disadvantage of the latter is that if the chelating agent is not applied properly, it may lead to potential environmental risks, such as soil element leaching, water pollution, and chelating residues. Volatilization will cause metal stress to plants, thus limiting the large-scale application of artificial chelating agents

In short, the existing two types of substances and methods for treating heavy metal-contaminated soil are not ideal.

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