Polymer-enhanced ultrafiltration: Fundamentals, applications and recent developments

This paper provides a comprehensive review of the fundamentals and recent progresses in polymer-enhanced ultrafiltration (PEUF) for the removal of environmentally toxic contaminants from wastewaters. The general principles, the selection of ultrafiltration membranes as well as the criteria of functional water-soluble polymers used in PEUF are firstly discussed. The interactions between water-soluble polymers and the target solute contaminants to be removed from aqueous systems are reviewed, and special emphasis is paid on to the equilibrium chemistry for polymer-metal ion interactions. The experimental approaches to evaluating the interactions between polymers and heavy metals developed to date have also been critically reviewed. Various parameters involved in the PEUF process (including metal to polymer loading ratio, pH and ionic strength of solutions, transmembrane pressure, and operating temperature) are discussed. Prior work on the subject matter that has been reported to date in the literature has been compiled and re-evaluated for comparisons in an attempt to provide an insight into this process and to highlight some of the research needs yet to be done for further development.