Ionic conductive membrane for chlorine-alkali industry and preparation method thereof

Abstract

The invention relates to the technical field of ionic membranes, and particularly relates to an ionic conductive membrane for a chlorine-alkali industry and a preparation method thereof. The ionic conductive membrane comprises a perfluorinated ion exchange resin base membrane, a micro-porous reinforcing material and a surface layer of a perfluorinated ion exchange resin microparticle. The perfluorinated ion exchange resin microparticle is a mixture of one or two of a perfluorinated carboxylic acid resin microparticle or perfluorinated sulfonic acid-carboxylic acid copolymer resin microparticle and a perfluorinated sulfonic acid resin microparticle, wherein the perfluorinated sulfonic acid resin microparticle accounts for 95%-50% of the percentage by mass of the mixture. The surface layer of the ionic conductive membrane has good compatibility and adhesion and maintains a good degassing effect in the whole service life of the ionic conductive membrane. An alkali metal chloride solution of which the range of concentration is wide can be efficiently and stably treated by the ionic conductive membrane in the chlorine-alkali industry, and the ionic conductive membrane is applicable for running in a zero-pole electrolytic cell under a novel high current density condition and a very excellent product purity index is achieved. The invention also provides a preparation method of the ionic conductive membrane, the process is simple and reasonable and industrial production is easily achieved.

Description

technical field [0001] The invention belongs to the technical field of ion membranes, and in particular relates to an ion conduction membrane used in the chlor-alkali industry and a preparation method thereof. Background technique [0002] In recent years, in the production of chlor-alkali by ion-exchange membrane method, in order to realize electrolysis under the conditions of high current density, low cell voltage and high concentration of lye, in order to achieve the purpose of increasing productivity and reducing power consumption, the key is to shorten the ion-exchange membrane The distance between the electrode and the electrode can be reduced to reduce the cell voltage, so that the narrow pole distance ion membrane electrolysis process can be practical. With the continuous advancement of technology, the zero-electrode distance electrolyzer has been widely used, but when the distance between the electrodes is reduced to less than 2mm, the hydrogen bubbles attached to t...

AI Technical Summary

Problems solved by technology

The hydrophilic coating modification process needs to be mixed with inorganic components and special binders, and then covered on the surface of the ion membrane by electrolytic deposition, particle embedding, etc. Patents CA2446448 and CA2444585 have introduced the coating process in detail ; Although the effect of this modification method is remarkable, the process is relatively complicated

In addition, because the ionic membrane will experience continuous scouring and turbulence caused by the lye flow during the electrolysis operation, the hydrophilic coating attached to the surface of the ionic membrane will gradually fall off, and the anti-foaming function will gradually decrease to ineffective.

[0004] The patent US4502931 mentions that the surface of the ionic membrane is roughened by ion etching, but this method is not easy to implement in a large area, and the anti-foaming ability is not high. When the distance between the electrodes is reduced to a certain extent, the groove voltage is still greater than 3.5V, and the current efficiency is less than 90%