Iron-rich biochar filters arsenic from water Biochar may be a fast inexpensive and easy way to remove arsenic one of the world s most common pollutants from water.For a new study researchers used used iron-enhanced carbon cooked from hickory chips to successfully remove the toxin. Arsenic finds its way into drinking water supplies through natural or human-made sources affects millions of people worldwide and has been shown to cause cancer.�Because biochar can be produced from various waste biomass including agricultural residues this new technology provides an alternative and cost-effective way for arsenic removal� says Bin Gao associate professor of agricultural and biological engineering at University of Florida.As reported in the journal Water Research Gao ground wood chips that were then heated in nitrogen gas but not burned. The resulting biochar which has the consistency of ground coffee was then treated with a saltwater bath to impregnate it with iron.Plain biochar does not have the same effect Gao says.Current methods to remove arsenic include precipitation adding lime or coagulants to water using membranes to filter it out or using an ion exchange process. But using a filter for removal is one of the most commonly used methods due to its ease of operation relatively low cost and high effectiveness.Water treatment plants could use large biochar filters to extract the arsenic. Homeowners could use a small filter attached to their tap.Further research is needed to optimize the process and to develop commercially available filters Gao says. The National Science Foundation partly supported the research.