Advanced oxidative treatment of saline-impacted waters

ENVR 146

Janel E. Grebel, janel.grebel@yale.edu1, Joseph Pignatello2, and William A. Mitch, gh17@umail.umd.edu1. (1) Department of Chemical Engineering, Yale University, Mason 308, 9 Hillhouse Ave, New Haven, CT 06520, (2) Department of Soil and Water, The Connecticut Agricultural Experiment Station, 123 Huntington St., P.O. Box 1106, New Haven, CT 06504
Advanced oxidation processes (AOPs) are used to remove organics from a variety of waters and wastewaters, many containing high concentrations of halide salts. Halides act as HO•-scavengers, forming reactive halogen species (RHS) during AOP treatment. The purpose of this research is to evaluate the impacts of salinity on AOP treatment in order to develop design criteria for treatment of saline-impacted water. Modeling of OH• and RHS concentrations indicates that RHS concentrations will exceed that of OH• by several orders-of-magnitude in brackish waters. RHS are reactive toward many organics; however, they have more selective reactivity than OH•. AOP treatment of model compounds, including phenol and oleic acid, shows retardation of removal rates as well as formation of halogenated products in the presence of halides. Preliminary data also shows halogen incorporation into dissolved organic matter (DOM) when OH• forms in the presence of halides.