Evaluation of Formate as an Electron Donor to Facilitate Palladium (PD) - Catalyzed Destruction of Chlorinated Aliphatic Hydrocarbons

摘要

The focus of this study was to detennine the effectiveness of using a palladium (Pd) catalyst with fonnate as a reductant to treat CAlI-contaminated groundwater. TCE was used as a model CAll. Other investigations(caret) have focused on hydrogen gas Hv as a reductant to treat CAlI-contaminated groundwater. However, when using H2as a reductant, catalyst deactivation is observed due to the production of hydrochloric acid. In this study, fonnic acid was used as the reductant, resulting in no observed catalyst deactivation even at high contaminant concentrations. Reaction rates achieved when using 100% H2 as a reductant could be matched by using 4 rnM (184 mg/L) fonnic acid. At increased fonnic acid concentrations,system performance exceeded performance achievable when using H2. It is also noted that while hydrogen is an explosive, low solubility gas, fonnic acid can easily and safely be added to contaminated water. The aforementioned work has shown that this method for treating CAlI- contaminated groundwater by using fonnic acid and a Pd-catalyst is more efficient, safe, and less costly than using hydrogen gas as a reductant.