Synthesis of a Novel Amphiphilic and Cationic Chitosan‐Based Flocculant for Efficient Treatment of Oily Wastewater

Abstract

ABSTRACTThis study reported the successful synthesis of a new amphiphilic and cationic flocculant (denoted as CS‐g‐PDBC) by grafting a cationic monomer, dimethyl acryloyloxyethyl benzyl ammonium chloride (DBC), onto chitosan (CS) initiated by ceric ammonium nitrate. The molecular structure and surface morphology of the newly synthesized graft copolymer CS‐g‐PDBC were characterized in detail by using Fourier transform infrared spectroscopy, X‐ray powder diffraction, field emission scanning electron microscope, thermogravimetric analysis , and elemental analysis. Moreover, its flocculation efficiency for treating simulated emulsified oil wastewaters was evaluated and the results indicated that CS‐g‐PDBC was more efficient than those of CS and two other commonly used flocculants, i.e., cationic polyacrylamide and polyaluminum chloride. It was found that, as compared with CS, the successful introduction of cationic and hydrophobic groups into the CS backbone resulted in a significantly broadened flocculation window and a greatly enhanced flocculation efficiency for the prepared CS‐g‐PDBC in the treatment of oily wastewater, suggesting that this newly synthesized CS‐g‐PDBC would be a promising green agent for oily wastewater treatment.