Preparation method of heavy metal polluted soil stabilizer

Abstract

The invention discloses a preparation method of a heavy metal polluted soil stabilizer, belonging to the technical field of soil remediation and treatment. The preparation method is characterized by comprising the following steps: blasting air or carbon dioxide gas under the conditions that polymine is used as a skeleton and a magnesium compound is used as an alkaline modifier and tetramethylammonium hydroxide is used as a carbon dioxide absorbent, and adding carbon disulfide to synthesize a mixture of a polymer chelating agent and a magnesium carbonate microcrystal; and adding ferric salt and carrying out chelating, oxidization/reduction, precipitation and adsorption to realize the efficiently stabilization of heavy metals in the polluted soil. In the stabilizer, the mass ratio of polymine to magnesium compound to tetramethylammonium hydroxide to ferric salt is 1:(0.2-0.6):(0.05-0.1):(0.1-0.5), wherein the molar weight of introduced carbon dioxide is at least 20% of that of magnesium ions and any amount of water is added. The stabilizer can be a solution or a crystal substance. The stabilizer is simple in synthetic technology and can realize efficient and fast stabilization of various heavy metals while carbon sequestration.

Description

technical field [0001] The invention belongs to the technical field of soil remediation and treatment, and in particular relates to a method for preparing and using a stabilizer for heavy metal polluted soil. Background technique [0002] In recent years, heavy metal pollution incidents have occurred from time to time, especially the problem of heavy metal soil pollution is becoming more and more apparent. The area of ​​soil pollution in my country is increasing year by year, and it has not been effectively controlled. It has become one of the important environmental problems. [0003] For the remediation and treatment of heavy metal soil, stabilization technology is a relatively mature and economically feasible method, and there are currently specific implementation cases at home and abroad. However, from the perspective of existing applications, cement-based reagents are mainly used as stabilizers for restoration, and there are problems of large volume increase ratio and l...

AI Technical Summary

Problems solved by technology

The soil stabilizer proposed in the invention patent with application publication number CN 102343357A mixes a variety of inorganic salt mineral materials to achieve the stabilization of heavy metals. The main components are clay minerals and silicates, and there is still a compatibilization comparison during use. Big problem; application publication number is CN 102335494A invention patent uses alkaline reagent as stabilizer, the stabilizing effect is easily affected by acid solution, it is difficult to ensure long-term stability; publication number is CN 1631940A invention patent uses polyamine or poly Ethyleneimine is a skeleton synthetic chelating agent, which has good stability of heavy metals. However, this method uses organic reagents as the main body. In the application process, there are problems such as high reagent costs, organic reagents are greatly affected by temperature, and long-term biological instability.