Development of responsive biopolymer materials: Investigation of their structure and adsorption properties
Lee D Wilson
University of Saskatchewan, Canada
: J Nanomater Mol Nanotechnol
Abstract
Statement of the Problem: There is a need to develop improved biopolymer adsorbents with responsive properties and enhanced adsorption toward target species for specialized applications in water treatment. In this study, polymer brushes and their iron oxide composites were prepared and characterized, along with the efficacy of methylene blue (MB) removal from aqueous solution. These “smart” materials were designed by grafting biodegradable Polymers Polyacrylic Acid (PAA) or poly itaconic acid (PIA) onto chitosan to yield pH-responsive polymer brushes of PAAgCHI, PIAgCHI and their magnetic nanocomposites (MNCs) containing iron oxide, respectively. The MNCs are pH-sensitive and magnetically responsive adsorbents with switchable polymer morphology between swollen and collapsed states, along with the controlled adsorption and desorption of MB. Switchable MB uptake is based on the pH driven molecular recognition and conformational changes of brushes. The adsorption capacity of the materials varies between 421.2 to 470.2 mg g–1 with a removal efficiency of 99.2% (Fe3O4–PIAgCHI) and 99.5% (Fe3O4–PIAgCHI) for the MNCs. Sorbents can be recovered and efficiently regenerated by switching the pH of a solution under an applied external field over five recycle steps. This work illustrates the potential utility of “smart” polymer brush systems for the remediation of model cationic dyes in wastewater. These eco-friendly sorbent materials possess excellent adsorption capacity, modular design, low cost, excellent regeneration, and rapid separation. Potential applications of these materials include the controlled removal of antimicrobials, pesticides, and personal care products from water and wastewater streams with high efficiency and recovery.
Biography
Wilson is affiliated with the Department of Chemistry at the University of Saskatchewan and is an Associate Professor with research interests that cover diverse topics in physical chemistry, materials science and environmental chemistry. Ongoing research activities are focused on the development of new types of materials and studies related to adsorption and interfacial phenomena related to water science and technology. The Wilson lab is developing new forms of sustainable biomaterials for the controlled removal of contaminants from water and chemical separations using methods based on green chemistry. This research contributes to the science and technology of “smart” adsorbent materials and applications that range across water and energy security.
E-mail: lee.wilson@usask.ca
