Reactive Fe0 Composite for Groundwater Remediation

S.L. Foster, M. Abolhassani, A. Carpenter, C. Gause, L. F. Greenlee
CatalyzeH2O, LLC,
United States

Keywords: zero valent iron, Trichloroethylene, groundwater remediation, permeable reactive barrier

Summary:

Over the past 100+ years, industrial processes have left groundwater contaminated with hazardous halogenated chemicals. The same physical and chemical properties of halogenated chemicals that made them attractive for industrial use (i.e. stable and resistant to degradation) makes them dangerous to the environment. Halogenated chemicals are known to persist, due to long half-lives, and migrate into residential and commercial areas. The ability to resell the land, expand the facility, or reuse the water, all depend on the decontamination of this hazardous groundwater. Although, substantial amounts of money have been invested in detoxifying contaminated sites around the United States, many have not been fully remediated over the years due to lack of detoxification technology in the industry. Permeable reactive barriers (PRB) are becoming a competitive option for groundwater remediation in the United States. PRB treat the contaminated water source by injecting a reactive material in the flow path of the water. Specifically, nanoscale zero valent iron (nZVI) composite materials have been shown to increase degradation of contaminated groundwater through in-situ treatment. Although, the larger surface area of the nZVI leads to higher reactivity and more effective degradation of contaminants, these fine particles are unstable in solution and often agglomerate. Agglomeration decreases a reactive materials area of influence through impaired transport into the subsurface. Our innovation, in collaboration with AxNano, has proved to aid in stability, degradation of Trichloroethylene, and transport of composite 5-10x farther for our synthesized nZVI compared to commercial options.