Highly selective alicyclic polyamide nanofiltration membrane and making method thereof

摘要

The present invention discloses a highly selective alicyclic polyamide nanofiltration membrane and a making method thereof. The method comprises the following steps: alternately and uniformly coating at least an alicyclic acid chloride solution and at least an alicyclic amine solution on a porous support membrane, using a spin coating method or a soaking method, to form at least one layer of the alicyclic polyamide nanofiltration membrane. Preferred embodiments exhibit improved ion selectivity, e.g. increased water flux, enhanced divalent/monovalent rejection selectivity, reduced fouling and improved divalent rejection rate (Ca²⁺, Mg²⁺) compared to the traditional aromatic-alicyclic mixed-structure polyamide nanofiltration membrane and/or the whole aromatic polyamide nanofiltration membrane. Therefore, the alicyclic polyamide nanofiltration membranes made in the present invention has great application prospect in the fields of zero-liquid discharge of industrial wastewater, water softening, and produce water treatment, etc.