Remediation of environmental waters by arsenic removal using polymer inclusion membranes

Arsenic is a metalloid widely spread in the earth's crust and is often found in conjunction with copper, gold, lead and iron in metal sulphide ores. The depletion of arsenic from ore deposits can lead to the presence of arsenic in aquifers and water streams. In recent years, the number of people exposed to arsenic in drinking water has increased. Prolonged drinking of arsenic contaminated water can cause serious health issues, including cancers. This risk to public health has increased the necessity for alternate, easy-to-use and environmentally friendly techniques for arsenic removal.

Polymer inclusion membranes (PIMs) have recently emerged as a promising alternative to conventional liquid-liquid extraction for the extraction and removal of various organic and inorganic pollutants from aqueous solutions. PIMs consist of three main components: a polymer to provide mechanical support, a carrier as the extractant for the targeted analyte, and a plasticizer or modifier to influence the physiochemical properties of the PIM. Investigating the chemistry of extraction is important because the membrane composition can have a significant effect on the selectivity and extent of analyte extraction. Our aim is to investigate the chemistry of inorganic arsenic removal from water using newly developed carriers, and to optimise the PIM performance for arsenic speciation and transport.