Reduced Iron Sulfide Systems for Removal of Heavy Metal Ions from Groundwater
Abstract
In this research, we have evaluated iron sulfide for treating heavy metal contaminated groundwater plumes for PRB systems. Our approach was to test the effectiveness of reduced iron sulfide (FeS) as both a sorbent and reducing agent in PRB applications for long-term sequestration of heavy metal ions. Cadmium (Cd) and Arsenic (As) were the targeted contaminants. Mechanistic information on the metal removal mechanisms was obtained by molecular-scale surface techniques including synchrotron-based XAS and XRD, and microscopic tools such as HRTEM and SEM-EDS. FeS performance under various geochemical conditions was investigated using batch and column reactor systems. Two different forms of reactive sorbent media were prepared, nanoscale FeS and FeS-coated sand for two emplacement methods, colloidal injection and physical packing of porous media, respectively. Rejuvenation of FeS using sulfate reducing micro-organisms for biogenic formation of FeS from iron oxidation products was examined and shown to be feasible. Finally, a reactive transport model was developed using batch isotherm and column arsenic breakthrough data. The overall results provide tools needed to design and apply the FeS PRB media for effective long-term treatment of mixed-metal ion plumes at contaminated groundwater DOD sites.
Document Details
- Document Type
- Technical Report
- Publication Date
- Jul 01, 2009
- Accession Number
- ADA512771
Entities
People
- Avey H. Demond
- Kim F. Hayes
- Linda Abriola
- Peter Adriaens
- Terese Olson
Organizations
- University of Michigan