Nanoparticles of zirconium oxide, says Arup SenGupta, P.C. Rossin Senior Professor of civil, environmental, and chemical engineering, possess adsorption properties that make them uniquely beneficial to human beings. They can remove four major toxins — arsenic, fluoride, phosphate and lead — from water.
SenGupta, a highly-awarded, three-decade pioneer in engineering for clean water around the world, and his students have extended their lab’s impact on global health, using zirconium oxide nanoparticles to invent the world’s first filter capable of removing both fluoride and arsenic from groundwater.
Nearly 400 million people in Asia and Africa drink groundwater that contains toxic levels of these contaminants. Exposure to excessive amounts of fluoride can cause skeletal fluorosis; this decreases the elasticity of bones, making them more prone to fracture and causing bone and joint damage. Elevated levels of arsenic can cause skin lesions, a variety of cancers and blood vessel disorders.
The materials used in the filter are polymeric ion exchangers doped with zirconium oxide nanoparticles. The doping procedure, says SenGupta, plays a critical role in producing optimum hybrid particles that are robust and accessible to water while maintaining their integrity. In late 2015, SenGupta and Surapol Padungthon ‘13PhD earned a U.S. patent for the invention.
SenGupta’s team was initially attracted to zirconium because of its filtering potential. Zirconium oxide nanoparticles pose no health hazard, says SenGupta, and they offer unique properties that help remove harmful contaminants from water.
“This is the only material currently available that can remove both arsenic and fluoride, and it can be reused for years without being wasted,” he says.
SenGupta has also developed a business model that enables people who lack clean groundwater to install and operate purification systems in an economically sustainable way. He and PhD candidate Mike German recently received the 2016 VentureWell-Lemelson Sustainability Award for co-founding DrinkWell, an organization that provides purification technologies and business opportunities to people who lack access to clean water.