Evaluation a self-assembled anionic polyacrylamide flocculant for the treatment of hematite wastewater: Role of microblock structure

Self-assembly is able to control molecular structure of flocculants and improves their flocculation efficiency. In this study, template polymerization and ultrasonic initiation system attributed to the self-assembly of anionic polyacrylamide (TPAS-U) with a microblock structure using acrylamide (AM) and sodium p-styrene sulfonate (SSS) as monomers and poly (allylammonium chloride) (PAAC) as template. The functional groups and ordered microblock structure in TPAS-U were discovered via characterization analysis. Association constant (K-M) manifested the self-assembly mechanism. And the role of ultrasonic in the synthesis was discussed as well. TPAS-U with well-organized/special structure had excellent flocculation performance in the treatment of hematite wastewater over other anionic flocculants. The flocs formed by TPAS-U possessed the big size, the compact structure and the strong recover ability after breakage. The uniform and regular microblock structure in TPAS-U attributed to the high utilization efficiency of negative charges, which improved neutralization, adsorption and bridging in the treatment. (C) 2018 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.