Ion-conducting membrane and preparation method thereof

Abstract

The present invention belongs to the technical field of ion membranes, and specifically relates to a novel ion-conducting membrane, consisting of a perfluorinated ion exchange resin base membrane, a porous reinforcing material and a surface layer made by mixing perfluorinated ion exchange resin microparticles and inorganic compound particles. The inorganic compound particles are selected from one or a mixture of any of oxides, hydroxides and nitrides of group IV-A elements, group IV-B elements, group V-B elements, iron, cobalt, nickel, chromium, manganese and boron. The perfluorinated ion exchange resin microparticles are a mixture of one or both of perfluorinated carboxylic acid resin microparticles and perfluorinated sulphonic acid carboxylic acid copolymer resin microparticles and perfluorinated sulphonic acid resin microparticles. The present invention is used in the chlor-alkali industry, and stably and effectively treats alkali metal chloride solutions having a wide range of concentrations. The present invention is suitable for operating in a zero pole distance electrolyser under novel high current density conditions, and product purity is high. Also provided is a preparation method for the novel ion-conducting membrane. The preparation method has a simple and reasonable process, and facilitates industrial production.

Description

technical field [0001] The invention belongs to the technical field of ion membranes, and in particular relates to a novel ion conduction membrane 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 the membrane surface are diffi...

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] Patent US 4502931 mentions that the surface of the ionic membrane is roughened and modified by ion etching, but this method is not easy to implement in a large area, and the anti-foaming ability is not high. The cell voltage is still greater than 3.5V, and the current efficiency is lower than 90%