High Rate and Cost Effective Arsenic Removal in Drinking Water Using Nanofibrous MnO2 and GFH Materials

The US Airforce seeks innovative water filtration systems to reduce arsenic level in drinking water to meet the EPA's new 10ppb limit. This arsenic limit will take effect in 2006, and will not be waived or deferred by EPA, which increases urgency fordeveloping advanced filtration media. Inframat Corporation proposes to demonstrate the feasibility of exploiting a nanofibrous manganese dioxide bird's-nest superstructure for DOD's arsenic removal in drinking water applications. The proposed programwill use an innovative hybrid water treatment system by combining the nanofibrous MnO2 oxidative process with the granular ferric hydroxide adsorptive process to remove arsenic in drinking water. The unique nanofibrous MnO2 is highly porous and expectedto overcome drawbacks, such as low surface area, limited catalytic activity, sensitive to stripping of the MnO2 surface due to the presence of highly reducing sulfide or to overly aggressive backwashing, in current commercial solid-phase oxidants. Theproposed program involves synthesis of the nanofibrous MnO2 bird's-nest superstructure, construction of filtration media, and testing of the filtration media with NSF Challenge Water spiked with 50ppb arsenic(III) at pH 7. The proposed program is a jointcollaboration between Inframat and Dr. Dennis Clifford of the Univ. of Huston. The proposed research project will result in a high-rate and cost-effective hybrid system combining As(III) oxidation by nanofibrous MnO2 followed by As(V) removal bygranular ferric hydroxide (GFH). Therefore, we expect this research to have a large impact in the water treatment industry. The commercial applications of the proposed technology include well water and other small and larger community water supplies.