Reactivity of Effluent Organic Matter (EfOM) with Hydroxyl Radical As a

Environ. Sci. Technol. 2010, 44, 5714–5720

Reactivity of Effluent Organic Matter (EfOM) with Hydroxyl Radical as a Function of Molecular Weight MEI MEI DONG,† STEPHEN P. MEZYK,‡ A N D F E R N A N D O L . R O S A R I O - O R T I Z * ,† Department of Civil, Environmental and Architectural Engineering, 428 UCB, University of Colorado at Boulder, Boulder, Colorado 80309, and Department of Chemistry and Biochemistry, California State University at Long Beach, 1250 Bellflower Boulevard, Long Beach, California 90840

Received February 11, 2010. Revised manuscript received June 4, 2010. Accepted June 10, 2010.

The application of advanced oxidation processes (AOPs) for the treatment of wastewater is hindered by scavenging of the hydroxyl radical (HO•) by effluent organic matter (EfOM). This scavenging is directly proportional to the second-order reaction rate constant between EfOM and HO• (kEfOM-HO•). To understand the kinetics of this reaction as a function of the subcomponents of EfOM, four wastewater samples were fractionated by ultrafiltration into distinct apparent molecular weight (AMW) fractions (