Tubular composite nanofiltration membrane

Abstract

The invention discloses a tubular composite nanofiltration membrane which comprises four functional layers, namely a support layer, a base membrane layer, an interfacial polymerization layer and a protective layer. A tubular base ultrafiltration membrane is formed by carrying out blending modification on polyethersulfone and an inorganic nanometer material, and a tubular polyamide composite nanofiltration membrane is formed by carrying out interfacial polymerization reaction on piperazine hexahydrate as a water-phase solution and a trimesoyl chloride hexane solution. According to a preparation process, a process technology of preparing a tubular polyethersulfone ultrafiltration membrane by adopting a jelly and synchronously producing the tubular polyethersulfone ultrafiltration membrane by adopting reel pipe welding and membrane coating is adopted. The obtained tubular composite nanofiltration membrane disclosed by the invention has the advantages of different selective separation functions on a monovalent ion and a divalent ion, a higher interception rate on a small-molecular organic matter, lower requirements on the pretreatment of feed liquid, applicability on the separation of high-solubility high-granularity high-suspension matters, and very high economic values on deep separation, purification and soluble shrinkage of some specific materials.

Description

[0001] The patent application of the present invention is a divisional application of Chinese patent application number 201310156264.1. The application date of the original application is 2013-4-28, and the application number is 201310156264.1. The name of the invention is a tubular composite nanofiltration membrane and its preparation method. technical field [0002] The invention relates to a polymer separation membrane, in particular to a tubular composite nanofiltration membrane. Background technique [0003] Polymer separation membranes can be divided into microfiltration membranes, ultrafiltration membranes, nanofiltration membranes and reverse osmosis membranes according to their pore size. According to different sources of polymer materials, it can be divided into polymer separation membranes prepared from natural polymer materials and polymer separation membranes prepared from synthetic polymers. Natural polymer materials are mainly cellulose acetate and its derivat...

AI Technical Summary

Problems solved by technology

However, the current composite nanofiltration membrane has a low rejection rate for small molecular organics and has high requirements for the feed liquid. In the application of traditional separation processes, a combination of multiple levels of different membrane separation precision is required to achieve finer separation. Screening, such as the separation and screening of some monovalent ions and divalent ions, etc., needs to be carried out many times, the cost is high, and it is not ideal in the deep separation, purification, and shrinkage applications of some special materials