AWWA WQTC58882

Advanced Oxidation Processes (AOPs) are now recognized to be a potentially inexpensive and relatively easy means to achieve degradation of important contaminants in water. The effects of AOPs on emerging contaminants such as those on the Candidate Contaminant List (CCL) need to be assessed systematically in a variety of water quality matrices. The objectives of the research are to evaluate the degradation kinetics and byproducts of select CCL contaminants using a combination of AOP processes including ozone, ozone/peroxide, ozone/UV, and UV/peroxide. In addition, the relative OH radical production efficiency of each of these AOPs will be assessed under select challenging water quality matrices. It is hypothesized that AOPs will be an effective means to degrade many CCL contaminants and that with proper system design, water quality challenges found in typical treatment scenarios will not compromise effective AOP treatment. The research approach integrates the expertise and experience of the co-investigators in environmental chemistry and advanced oxidation process design to address these important questions and others. In Phase I, specific groups of contaminants on the US Environmental Protection Agency CCL will be evaluated for AOP treatment response using numerous AOP processes. Initially, these CCL contaminants will be evaluated in groups, based on chemical structure and commonality in analytical methods to determine the least reactive chemicals in each group. Based on these results, select contaminants will be used in Phase II to evaluate the impacts and interactions of AOP operational parameters and water quality (e.g. total organic carbon, alkalinity, pH) on contaminant degradation and product distribution. A statistical experimental design will be utilized in Phase II. Finally, to provide fundamental information on the AOP processes important to successful implementation and engineering, Phase III will investigate the OH radical production efficiency of each AOP tested under select water quality scenarios identified in Phase II. Competition for hydroxyl radicals between contaminants and natural water constituents, such as total organic carbon and alkalinity will be investigated, and the results should aid AOP design by indicating how best to incorporate upstream treatment systems. Includes tables, figures.