Removal of direct red dye using polysulfone-chitosan ultrafiltration membrane

Abstract

Textile industries are one of the largest pollution contributor to the environment through high amount of wastewater discharge that contain high concentration dyes. The present state of application of using membrane technology in the removal of dyes from textile wastewater has shown positive pathway for this research. Chitosan are biopolymer that are naturally occurring. It is used as a hydrophilic additive in the fabrication of polysulfone (PSF) and chitosan (CS) membrane. Different loadings of CS at 0.1, 0.3, 0.5, 0.7 and 1.0wt% were used. The fabricated PSF-CS membrane by phase inversion method were characterized using SEM for its morphology, FTIR for its functional group and contact angle for membrane hydrophilicity. As the addition of CS increase the hydrophilicity of the PSF-CS membrane, excessive CS precipitation was observed at chitosan loading at 1.0wt% creating a large macro void causing lower permeation performance. It is found that PSF-CS membrane with 0.7wt% has the best contact angle and dye rejection performance of 65.49º and 99.78%.