Recent progress in development of high performance polymeric membranes and materials for metal plating wastewater treatment: A review

Development of advanced technologies for metal plating wastewater treatment constitutes one of the major fields of research, primarily driven by the progressive environmental regulations issued to address the concerns. The emergence of various membrane-based processes and the satisfactory trial and field tests have created new avenues for minimization of the negative impacts caused by the uncontrolled discharge of metal plating waste streams. On the other hand, the progress in the polymer science and engineering provides opportunities for development of membrane materials with advanced functionalities and superior characteristics that can effectively be employed for design and fabrication of high performance membranes. The present review provides an overview on the specifications of metal plating wastewater streams and the significance of the treatment by presenting possible strategies that can be employed for heavy metal removal. Special attention is paid to nickel, chromium and zinc due to their high impacts and detrimental effects. In addition, a comprehensive review is provided on the recent advances in development of high performance polymeric materials for diverse membrane-based processes including reverse osmosis (RO), nanofiltration (NF), ultrafiltration (UF), complexation–ultrafiltration (CUF), microfiltration (MF), polymer inclusion membranes (PIMs), electro-membranes (EMs), hybrid processes, liquid membranes, emulsion liquid membranes (ELMs) and membrane-based solvent extraction by highlighting the role of molecular design and architecture and other featured characteristics in the process performance and efficiency.