IFAT 2018

••• 19••• Innovationen Clean water in seconds Metal organic framework removes heavy metals easily A n estimated one billion people do not have access to clean drinking water, a problem expect- ed to worsen with climate change, according to the World Health Or- ganization. Researchers now re- port in ACS Central Science a new material that can remove heavy metals and provide clean drinking water in seconds, the American Chemical Society (ACS) reports. There are many sources of expo- sure to toxic heavy metals. Lead, in particular, has been used in paints, ceramic glazes, jewelry, toys and in pipes. Current com- mercial methods to remove heavy metals including lead frommunici- pal drinking water can be expen- sive in terms of money and ener- gy and are inefficient. In addition, some current approaches either are single-use, are difficult to re- generate or can produce signifi- cant toxic waste as a side product. Wendy L. Queen and colleagues sought to attack this issue with materials called metal organic frameworks (MOFs) that are net- works of organic chemical ‘struts’ with metal nodes known to pull things like water and gases from air. That ability, plus the large sur- face area and chemical tunability of MOFs make them a promising material to remove heavy metals selectively from water. The researchers created a water- stable MOF/polymer composite with cheap, environmentally and biologically friendly materials and tested its ability to remove heavy metals from water. It had one of the highest reported removal ca- pacities to date, removing over 1.6 times its own weight of mercury and 40 per cent of its weight in lead. The researchers tested the MOFs in solutions with lead levels similar to those found in contami- nated water samples from Flint, Michigan. They found that the material can rapidly reduce lead concentrations to two parts per billion, which is the U.S. Environ- mental Protection Agency limit for drinkable levels. Background Further, the authors removed lead from various real-world wa- ter samples from the Rhone Riv- er, the Mediterranean Sea and a wastewater treatment plant in Switzerland. The researchers also demonstrated how the material could be regenerated easily with- out toxic products. The authors say they are now pursuing using other specially designed MOFs to remove other trace contaminants in water. The American Chemical Society is a nonprofit organization char- tered by the U.S. Congress. With nearly 157,000 members, ACS is the world’s largest scientific soci- ety and a global leader in provid- ing access to chemistry-related research through its multiple da- tabases, peer-reviewed journals and scientific conferences. A metal organic framework can remove lead fromwater samp- les, getting them to EPA-approved levels in seconds. Photo: American Chemical Society www.bollegraaf.com • info@bollegraaf.com &UHDWLQJ D ZRUOG RI GL΍HUHQFH