A method for removing cyanide in cyanide-containing wastewater by using ionic liquid supported liquid membrane technology

Abstract

A method for removing cyanide in cyanide-containing wastewater by using ionic liquid supported liquid membrane technology, using membrane hydrophobic polyvinylidene fluoride microporous filter membrane as porous carrier, and using 1-butyl-3-methylimidazole hexafluorophosphate It is an ionic liquid, and the porous carrier membrane is immersed in the ionic liquid by an impregnation method. Due to the effect of surface tension, the ionic liquid fills the membrane pores of the carrier membrane to form an ionic liquid supporting liquid film; the supporting liquid film is fixed in the feed liquid phase (cyanide) In the middle of the liquid waste water) and the analysis phase (sodium hydroxide solution), stirring and mass transfer are carried out on both sides of the liquid film, and finally enrichment and recovery of cyanide in the analysis solution; the present invention imitates the characteristics of active transport of biofilm, and has good selectivity, High separation efficiency, large enrichment multiple, low energy consumption, easy operation, short treatment cycle, cyanide can be recycled, easy for engineering application, and the advantages of reusable membrane phase, the removal rate can reach more than 95%, It can realize efficient treatment of cyanide and resource recovery.

Description

technical field [0001] The invention belongs to the technical field of environmental chemical industry, and in particular relates to a method for removing cyanide in cyanide-containing wastewater by using ionic liquid supported liquid membrane technology. Background technique [0002] In the process of industrial production, the sources of cyanide are very extensive. There are various production processes such as metallurgy, mineral processing, metal processing, plastics, electroplating, pesticides, coking, oil refining, heat treatment, and plexiglass / acrylonitrile synthesis. Etc. cyanide-containing wastewater discharged. Conventional methods for treating cyanide wastewater can be roughly divided into two types: destruction method and recovery method. The destruction method is mainly for low-concentration cyanide wastewater, and the recovery method is mainly for high-concentration cyanide wastewater and some cyanide wastewater containing recovery value metals. Alkaline chlo...

AI Technical Summary

Problems solved by technology

Alkaline chlorination is currently a widely used method for treating cyanidation wastewater in China. It has a relatively deep treatment degree and can better meet the needs of cyanide wastewater discharge. Its shortcoming is that it cannot destroy stable metal complexes; The treatment effect of the ferrate oxidation method is similar to that of the alkaline oxidation method, and no environmentally harmful substances are produced in the process of breaking cyanide, but its disadvantage is that the synthesis of the medicament is difficult and the cost is too high. Large-scale popularization and application in treatment; acidification volatilization-alkali absorption method is a traditional method for treating high and medium concentration cyanide wastewater. The impact is small, but the disadvantage is that the treated wastewater is generally difficult to meet the discharge standard, and secondary treatment is required to meet the discharge standard

Compared with other methods, the membrane separation method has no secondary pollution, can realize the recycling of pollutants, has low energy consumption, and has good economic effects, but the disadvantage is that the membrane pollution is more serious

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