High-throughput hollow fiber composite nanofiltration membrane, and preparation method thereof

Abstract

The invention discloses a high-throughput hollow fiber composite nanofiltration membrane. The high-throughput hollow fiber composite nanofiltration membrane is composed of a supporting layer and a separating layer; the supporting layer is prepared from a higher molecular hollow fiber ultrafiltration membrane; the separating layer is a polyamide layer obtained via interfacial polymerization of multi-amines and multi-acyl chlorides; pure water flux of the high-throughput hollow fiber composite nanofiltration membrane is high, and removing rates of the high-throughput hollow fiber composite nanofiltration membrane on NaCl in NaCl aqueous solution, and MgSO4 in MgSO4 aqueous solution are both high. A preparation method of the high-throughput hollow fiber composite nanofiltration membrane comprises following steps: nonsolvent induced phase separation method is adopted so prepare a high molecular hollow fiber ultrafiltration membrane; the high molecular hollow fiber ultrafiltration membrane is immersed into a multi-amine aqueous solution containing an acid-binding agent so as to obtain a nanofiltration memebrane precursor; the nanofiltration memebrane precursor is contacted with an organic solution of multi-acyl chlorides so as to form the polyamide separation layer and obtain hollow fiber composite nanofiltration membrane wires; and at last an oxidizing agent is used for oxidation treatment, and curing treatment is carried out so as to obtain a finished product. The high-throughput hollow fiber composite nanofiltration membrane is high in water flux, low in cost, and excellent in performance, and is convenient to prepare.

Description

Technical field [0001] The invention relates to a nanofiltration membrane and a preparation process thereof, in particular to a hollow fiber composite nanofiltration membrane and a preparation method thereof. Background technique [0002] Nanofiltration (NF) is a pressure-driven membrane separation process between reverse osmosis (RO) and ultrafiltration (UF), and is currently one of the most rapidly developing membrane separation technologies. It is generally believed that the separation pore size of nanofiltration membranes is 0.5-2nm, which can be used for the separation or purification of small-molecule organics with a molecular weight of 200-2000; most of the nanofiltration membranes have charged groups on the membrane surface or the membrane body, which can achieve The separation of ions of different valences (high rejection rate for divalent and higher valence salts, and medium rejection rate for monovalent salts) is sometimes called "selective reverse osmosis". [0003] Th...

AI Technical Summary

Problems solved by technology

[0007] The above-mentioned existing hollow fiber nanofiltration membrane preparation process has not yet been industrialized, and a commercially applicable hollow fiber nanofiltration membrane has not been effectively obtained. In addition, the nanofiltration membrane prepared by the existing technology has low water flux, which increases the use of users. The cost restricts the application and promotion of nanofiltration membrane technology

Images