Arsenic is a toxic element found naturally in groundwater. Long-term exposure over a number of years to elevated concentrations of arsenate, the chemical form of arsenic in water, is associated with debilitating, and potentially fatal, illnesses including cancer, heart and lung disease, gastrointestinal problems and neurological disorders.

Researchers at the Departments of Chemistry and Earth Sciences and Engineering have designed, tested and patented a new sorbent material that can selectively bind to arsenate with strong affinity. The team hopes this material could ultimately be used to improve quality of domestic water filters and reduce the amount of arsenic that people are exposed to in areas with known or suspected high arsenic content.

For many years the main focus of Dr Dominik Weiss’ research has been the uptake of micro-nutrients by plants and in particular how metallic ions interact with organic ligands (a ligand is an organic molecule that binds to a central metal atom), but he has also been taking an interest in pollutant adsorption and metallic atoms in water supply. On the other hand, Prof Ramon Vilar from the Chemistry Department has carried out extensive research in developing chemical receptors to ‘trap’ anionic species such as phosphates. The complementary expertise of these two groups and their interest in tackling environmental problems, led them to set up a PhD project in the area of arsenate remediation.  In 2011, Christopher Moffat joined the teams as a PhD student to tackle the challenging problem of developing functionalised materials for improved arsenic remediation.

The team started to explore novel chemical receptors to act as sorbents that could be used to remove arsenic ions in water supplies. The current industry standard is to use an Iron Oxide (Bayoxide E33), however, through their collaboration the team have now managed to develop a novel sorbent based on carefully tailored chemical receptors that is significantly more efficient at removing arsenic from water supplies. Supported by a NERC IAA award, the team have successfully demonstrated a lab-based prototype of the system and are currently undertaking market analysis to assess the commercial potential of the system through a NERC Pathfinder Award.

With WHO’s and other national guidelines on safe levels of arsenic increasingly being reduced, the team is ideally placed to deliver a novel highly efficient solution to arsenic removal capable of performing to these reduced levels.

For more information see:

http://www3.imperial.ac.uk/newsandeventspggrp/imperialcollege/newssummary/news_23-10-2014-11-7-51