Preparation method of anion-exchange membrane with univalence and multivalence selective separation functions

Abstract

The invention discloses a preparation method of an anion-exchange membrane with univalence and multivalence selective separation functions. The preparation method comprises following steps: 1, a DAS solution is prepared, wherein a certain amount of DAS powder is weighed, and is dissolved in pure water, the pH value of an obtained solution is adjusted with hydrochloric acid to 2 to 8 so as to obtain a DAS solution with a DAS concentration ranging from 3.0 to 7.0mg / ml; 2, one surface or the two surfaces of an anion-exchange membrane are immersed into the DAS solution so as to realize penetrationof DAS into the surface layers of the anion-exchange membrane; 3, after the above treatment, the anion-exchange membrane is subjected to ultraviolet irradiation so as to realize crosslinking of DAS with the membrane surface structure and immobilize DAS in the membrane surface structure; and 4, after crosslinking, the obtained anion-exchange membrane is immersed in pure water so as to obtain the anion-exchange membrane with univalence and multivalence selective separation functions. The preparation method is simple; membrane thickness is not increased; membrane resistance increasing is low; the obtained anion-exchange membrane possesses excellent univalent and multivalent anion selectivity and stability.

Description

technical field [0001] The invention belongs to the technical field of separation membranes, and in particular relates to a preparation method of a high-performance anion exchange membrane with single and multivalent selective separation functions. Background technique [0002] With the increasing depletion of global water resources and increasing water pollution, the problem of water shortage has become one of the biggest challenges facing the world. Seawater desalination, brackish water desalination and sewage treatment and reuse are important ways to solve water resource problems. At present, in the field of water treatment, a unique water treatment system including microfiltration, ultrafiltration, nanofiltration, reverse osmosis and electrodialysis has been formed. Among them, electrodialysis is a technology that uses the selective permeation performance of ion exchange membranes for ions, and is driven by an external DC electric field to make ions migrate in a directi...

AI Technical Summary

Problems solved by technology

However, the method of surface modification will increase the membrane thickness and reduce the ion exchange capacity while obtaining high selectivity, which will greatly increase the membrane resistance.

At the same time, most of the modified layer and the membrane resistor are connected together only by electrostatic interaction, and the modified layer is easy to fall off during use.

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