Preparation method for mulching film for repairing chromium pollution of soil

Abstract

The invention discloses a preparation method for a mulching film for repairing chromium pollution of soil. The mulching film is prepared from raw materials, including activated sludge, carboxymethylcellulose, ferrous sulfate, sodium borohydride, zinc chloride, chitosan, chloroacetic acid, silver nitrate, beta-cyclodextrin, polyacrylic acid, and so on. According to the invention, an absorbing material with a large aperture is acquired by calcining and modifying the activated sludge and is used for in situ absorbing metal chromium in soil; silver particle loaded chitosan, sludge activated carbon, and the like, acquired on the basis, and beta-cyclodextrin, and so on, are embedded; a stable fibrous membrane structure is formed through electrostatic spinning and thermo-crosslinking; a zero-valent iron liquor is prepared, dipped and carried on the fibrous membrane surface, so that the absorbed hexavalent chromium ions can be effectively reduced and the in-situ repairing of chromium pollutionin soil can be finally realized; and meanwhile, the used film material has the advantages of easiness in recycling and no secondary pollution, the repairing cost is reduced and the mulching film is suitable for the repairing of chromium pollution of various soils.

Description

Technical field [0001] The invention relates to the technical field of soil remediation, in particular to a preparation method of a soil chromium pollution remediation film. Background technique [0002] With the deepening of urbanization in recent years, the large amount of chromium-containing waste left by the relocation of many industrial enterprises in electroplating, chromium salt production, printing and dyeing, etc. has caused the problem of chromium pollution in the soil of the site. According to the content of promoting the comprehensive prevention and control of soil pollution, by 2020, the increasing trend of soil pollution across the country will be initially curbed, and chromium pollution, as a typical representative of soil heavy metal pollution, has been widely concerned. [0003] Chromium is generally in two valence states in the environment, namely trivalent chromium and hexavalent chromium. The toxicity and mobility of hexavalent chromium in the environment are s...

AI Technical Summary

Problems solved by technology

Usually, membrane materials can only retain bacteria and have no antibacterial or bactericidal functions. Therefore, membrane biofouling is a technical problem in the field of membrane use and separation technology.

[0005] Chitosan is a natural cationic polysaccharide, which has the advantages of wide sources, low price, non-toxic and harmless, and degradable. Its molecular chain contains a large number of amino groups and hydroxyl groups, which can form stable chelates with many metal ions. Due to the insoluble properties of chitosan in common solvents, its application is limited