Activated Carbon for Removing Tetrachloroethylene from Alcohol Solutions

Abstract

Alcohol (cosolvent) flooding is a relatively new, in situ technique for enhancing the removal of organic solvents from groundwater aquifers. Recovery of the alcohol for reinjection is important for ensuring the cost-effectiveness of this technology. The research goal was to investigate the ability of activated carbon to remove tetrachloroethylene (PCE) from alcohol solutions, allowing reuse of the alcohol in the cosolvent-flooding process. Laboratory studies were conducted using PCE (concentrations ranged from 10 to 100,000 mg/L) and isopropyl alcohol or ethanol. Alcohol concentrations ranged from 0 to 80% (v/v). A field application conducted at the Dover National Test Site in Delaware consisted of treating 60 to 70% (v/v) ethanol solutions containing PCE concentrations ranging from 500 to 2,000 mg/L with carbon-filled drums. PCE adsorbed onto activated carbon even at high alcohol concentrations; however, the Freundlich coefficient (