Fabrication of melamine-based hybrid organic membrane for ethanol/water pervaporation

Abstract

Covalent organic frameworks recently were utilized as membrane fillers for effective liquid mixture separation due to their intriguing structure. Though a facile dipcoating-wiping method, a melamine-based hybrid membrane was prepared where Chitosan (CS) was combined with SNW-1 (Schiff base network-1) on the surface of α -Al 2 O 3 support followed by crosslinking with calcium ions, a dense SNW-1/CS layer with thickness of 550 nm was successfully fabricated for ethanol/water pervaporation. The hydrophilicity of melamine-based membranes surface was enhanced by SNW-1 incorporation with improved anti-swelling property and thermal stability. The porous structure of SNW-1 offered free volume and fast channels for water transport. Consequently, the melamine-based membranes showed long-term stability and excellent separation factor of 373 with high permeance flux of 2.8 kg/(m 2 ·h). The fabrication of the SNW-1/CS hybrid membrane by dipcoating-wiping for ethanol/water pervaporation. • Melamine-based SNW-1 was incorporated into chitosan to fabricate COF-based SNW-1/CS hybrid membranes. • SNW-1 incorporation endowed the hybrid membrane with enhanced surface hydrophilicity, thermal stability and anti-swelling property. • Improved separation factor and permeance flux was observed on the SNW-1/CS hybrid membrane with long-term stability.