Bimetallic Zero Valent Iron-Carbon Composites for In Situ Remediation: Improving Particle Lifetime, Reactivity and Transport

The Environmental Protection Agency (EPA) estimates that one out of every four Americans lives within three miles of a hazardous waste site. Recent developments in advanced treatment materials has led to improvements driving increased use of In Situ Chemical Reduction (ISCR) at Superfund sites in the US and other contaminated zones around the world. Nanoscale Zero Valent Iron (NZVI) holds great potential for ISCR due to its low cost and high reactivity towards degrading halogenated and heavy metal contaminants. However, two major technical challenges prevent wide-spread NZVI adoption: 1) agglomeration, which prevents transport in the subsurface; and 2) passivation, which decreases reactivity to contaminants. AxNano, in collaboration with University of Arkansas, has developed a novel, three-component composite composed of bimetallic NZVI on a carbon-based substrate. This innovative composite design simultaneously addresses both technical challenges by preventing aggregation and slowing passivation, all while promoting reductive degradation of contaminants. This Phase I SBIR work effort will evaluate the ability of the AxNano composites to degrade trichloroethylene (TCE), transport through porous media, and to maintain composite stability under various environmental conditions. The result of this SBIR program will be a novel, low-cost remediation technology with broad-spectrum efficacy to meet market and society needs.