ZeroValent Iron Research

Prinicpal Investigators:
Dr. Christian Clauen, Dr. Cherie Geiger, Dr. Debra Reinhart, Dr. Andrew Randall

Funding Agencies: NASA, Gulf Coast Hazardous Substance Research Center

Project Description: The persistence and mobility of chlorinated hydrocarbons in the subsurface was largely unanticipated, therefore historical disposal practices have lead to widespread groundwater contamination. Zero-valent zinc and iron significantly enhanced the reductive dehalogenation of aliphatic compounds with iron being particularly attractive due to its low cost and availability. Zero-valent metals have application to groundwater treatment in both in situ and ex situ situations, however they are most frequently used as the reactive component of a permeable reactive barrier. It has been documented that the reactive process leads to precipitation or fouling of the zero-valent metal surface resulting in a decline of the degradation rate of this surface mediated process and possible reduction of the permeability of the treatment wall. The University of Central Florida has been involved in zero-valent research since 1994.

In 1998, UCF constructed a permeable reactive barrier at Kennedy Space Center's Launch Complex 34 using deep-soil mixing technology. On-going research at the University of Central Florida has investigated the use of sonication to enhance and/or restore the activity of the zero-valent metal through surface cleansing. This technology has application at dozens of present sites and potentially hundreds of future sites, as the reactive iron ages and declines in performance. Sonication application to field sites that have used zero-valent iron in permeable treatment walls for several years has been successful. Commercialization of this technique is an expected outcome of this demonstration. UCF has also explored the interaction of microbial activity with reactive iron. More recently, UCF is exploring the use of emulsified zero-valent iron to treat chlorinated DNAPL sources.