Preparation method of cross-linked chitosan modified shaddock peel adsorption material for removing low-concentration heavy metals in waste water

Abstract

The invention relates to a preparation method of a cross-linked chitosan modified shaddock peel adsorption material for removing low-concentration heavy metals in waste water and belongs to the field of waste water treatment. According to the preparation method, substances, such as chitosan, methanol water and the like, are filtered after being subjected to water circumfluence; filter residues are acid-pickled, alkaline-leached, washed and dried and are mixed with acetic acid and epichlorohydrin; after a pH value is regulated, the reaction is performed; by suction filtration, washing, drying and sieving, chitosan powder is obtained; then shaddock peel is obtained, is washed and dried and is ground into particles; the particles are added into sodium hydroxide solution and absolute ethyl alcohol for soaking; after centrifugation is carried out and the pH value is regulated, the obtained product is dried and is placed into a vacuum flask; in a negative pressure state, the obtained product is added into chitosan modification liquid for soaking; processing is carried out in a plasma form; filtration is carried out to obtain filter residues; and the filter residues are washed and dried to obtain the cross-linked chitosan modified shaddock peel adsorption material. In waste water treated by the cross-linked chitosan modified shaddock peel adsorption material prepared by the preparation method, mercury content is reduced to 0.5 to 1mg / L, nickel content is reduced to 0.5 to 0.7mg / L, and copper ion content is reduced to 0.04 to 0.05mg / L; treatment efficiency is high; secondary pollution cannot be generated.

Description

technical field [0001] The invention relates to a preparation method of a cross-linked chitosan-modified pomelo peel to remove low-concentration heavy metal adsorption materials in waste water, belonging to the field of waste water treatment. Background technique [0002] Most of the heavy metal wastewater comes from mining, mineral processing, smelting, metal processing and other enterprises. Through the food chain, it is easy to accumulate in organisms and endanger human health. The methods for treating heavy metal wastewater can be classified into three categories: chemical method, physical chemical method and biological method. Among them, chemical methods include neutralization precipitation method, sulfide precipitation method, ferrite precipitation method, barium salt precipitation method, etc.; physical and chemical methods include ion exchange method, adsorption method, solvent extraction method, liquid membrane method, reverse osmosis method and electrolysis method...

AI Technical Summary

Problems solved by technology

[0004] The technical problem mainly solved by the present invention: Although the chemical precipitation method can quickly remove metal ions in wastewater, but there are problems such as high metal concentration in the effluent, easy to produce secondary pollution, high calcium content in wastewater, and difficulty in recycling, etc., provides a A preparation method for cross-linked chitosan modified grapefruit peel to remove low-concentration heavy metal adsorption materials in wastewater. The present invention mainly uses cross-linked chitosan to treat low-concentration heavy metal wastewater, and combines the adsorption capacity of grapefruit peel for processing. The present invention The mercury content in the treated wastewater of the invention is 40-45 mg / L reduced to 0.5-1 mg / L, the nickel content is 30-40 mg / L reduced to 0.5-0.7 mg / L, and the copper ion 25-35 mg / L is reduced to 0.04-0.05 mg / L, high treatment efficiency, no secondary pollution