Polymer ultrafiltration membrane applied to polyamide composite membrane support and preparation method thereof

Abstract

The invention provides a polymer ultrafiltration membrane applied to polyamide composite membrane support, the polymer ultrafiltration membrane has a two-layer structure, the two-layer structure comprises a small pore structure layer close to a polyamide separation layer and a large pore structure layer adjacent to the small pore structure layer, the pore diameter of the small pore structure layeris about 5-20nm, the pore diameter of the large pore structure layer is about 50-500nm, and the small pore structure layer is doped with an aluminosilicate molecular sieve subjected to dealuminationtreatment. According to the invention, an ultrafiltration support body is improved, so that the spreading of a water-phase monomer on the surface of the membrane is ensured on the basis of ensuring the water flux.

Description

technical field [0001] The invention relates to an ultrafiltration membrane, in particular to a polymer ultrafiltration membrane applied to polyamide composite membrane support. Background technique [0002] Ultrafiltration membrane is a kind of membrane between microfiltration and nanofiltration. It has a wide range of applications, such as wastewater treatment, protein separation, etc., and among its many uses, it is used as a composite membrane support. In this application It mainly plays a supporting role, not mainly for separation purposes. It is a common application to apply the ultrafiltration membrane to the support of the polyamide composite membrane. Since the polyamide separation layer needs to contact the polyamine aqueous solution and the polyacyl chloride organic solution successively on the support layer, it has unique characteristics for the ultrafiltration membrane. Requirements, one is that the surface flatness of the ultrafiltration membrane is required t...

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Problems solved by technology

Molecular sieve is a common inorganic particle used for doping, and aluminosilicate microporous molecular sieve has high hydrophilicity, but the applicant found in the research that the use of aluminosilicate molecular sieve, especially silicon aluminum When a molecular sieve with a ratio of less than 10 is doped in the support body, it is very easy to undergo water adsorption and expansion during the water-phase monomer water dissolution contact process, resulting in difficulty in film formation