A highly hydrophilic organic solvent reverse osmosis membrane and its preparation method

Abstract

This invention discloses a highly hydrophilic organic solvent reverse osmosis membrane, its preparation method, and its applications. The organic solvent reverse osmosis membrane comprises a cross-linked polyimide porous support layer, a polyamide separation layer, and a surface grafting layer. The surface grafting layer is formed by the amidation reaction of D-glucosamine with residual acyl chloride groups on the surface of the polyamide separation layer via its primary amino group. This invention utilizes a D-glucosamine / ethanol solution to modify the surface of the nascent polyamide membrane, grafting D-glucosamine through a secondary interfacial reaction to avoid hydrolysis of residual acyl chloride groups, while simultaneously introducing a large number of hydroxyl groups onto the membrane surface. The prepared membrane exhibits significantly enhanced hydrophilicity, greatly increasing the permeation flux of polar organic solvents while maintaining a high solute rejection rate. The preparation method of this invention is simple, low-cost, and easy to scale up, showing broad application prospects in the field of polar organic solvent separation and recovery.