Use of a Novel Cationic Polymer/Bentonite Complex in the Removal of Non-ionic and Anionic Dyes from Dyeing Wastewater

摘要

A new cationic polymer/bentonite complex was prepared from intercalating polyepicholorohydrin-dimethylamine (EPI-DMA) into bentonite layers. The characterization of the new complex (EPI-DMA/bentonite) and its adsorption property for non-ionic dyes, namely, Disperse Blue SBL and Vat Scarlet R, and anionic dyes, namely, Reactive Violet K-3R and Acid Dark Blue 2G, were investigated. Due to the intercalation of EPI-DMA, the zeta potential of clay particles increased from -40.15 mV up to a net positive charge of +15.21 mV, the clay interlayer spacing expands from 12.54 (A) to14.97(A) and the clay particles were more hydrophobic, providing with better surface properties for adsorption. Based on the study of thermodynamics and kinetics of dyes adsorption onto EPI-DMA/bentonite, the different adsorption mechanism for non-ionic and anionic dyes were revealed, respectively. Finally, the color removal efficiency of actual textile wastewater treated by EPI-DMA/bentonite complex were compared with those treated by raw bentonite, and EPI-DMA, respectively, suggesting that EPI-DMA/bentonite complex was more effective in dyeing wastewater treatment.