Nanofiltration membrane as well as preparation method and application thereof

Abstract

The invention relates to a nanofiltration membrane, a preparation method thereof and application of the nanofiltration membrane in the field of water treatment. The nanofiltration membrane comprises a supporting layer and a polyamide separation layer which are attached to each other, and phytic acid is chelated on the surface of the polyamide separation layer. The polyamide separation layer and the phytic acid are chelated and crosslinked, so that the phytic acid is chelated on the surface of the separation layer. The phytic acid and amino groups on the surface of the polyamide functional layer are subjected to chelation cross-linking reaction, so that the cross-linking density of the polyamide separating layer is improved, and the hindering effect on salt ion permeation is enhanced; on the other hand, after the surface of the polyamide is modified by phytic acid, the hydrophilicity of the membrane is improved, and permeation of water molecules is facilitated. In addition, the nanofiltration membrane provided by the invention has excellent salt rejection rate and water permeability, the preparation method is simple, and the nanofiltration membrane has great industrial application prospects.

Description

technical field

[0001] The invention relates to the field of separation membranes, in particular to a nanofiltration membrane, a preparation method thereof and an application of the nanofiltration membrane in the field of water treatment. Background technique

[0002] Membrane separation technology is a new separation technology that appeared in the early 20th century and rose rapidly after the 1960s. Because membrane separation technology not only has the functions of separation, concentration, purification and refining, but also has the characteristics of high efficiency, energy saving, environmental protection, molecular level filtration, simple filtration process and easy control, it is widely used in food, medicine, biology, environmental protection, chemical industry , metallurgy, energy, petroleum, water treatment, electronics, bionics and other fields, and has produced huge economic and social benefits, and has become one of the most important means in today's separa...