Ultrasonic irradiation for the destruction of aqueous PFOS and PFOA

ENVR 143

Chad D. Vecitis, vecitis@caltech.edu1, Hyunwoong Park, hpark@caltech.edu1, Jie Cheng, jetcheng@caltech.edu1, Brian Mader, bmader@mmm.com2, and Michael R. Hoffmann, mrh@caltech.edu1. (1) Environmental Science and Engineering, California Institute of Technology, W. M. Keck Laboratories 138-78, 1200 E. California Blvd., Pasadena, CA 91125, (2) Environmental Research Laboratories, 3M Corporation, 3M Center, Building 260-05-N-17, Maplewood, MN 55144-1000
The perfluorinated surfactants, perfluorooctane sulfonate (PFOS) and perfluorooctanoate (PFOA) are widespread in the environment as well as bio-accumulative, persistent and recalcitrant toward conventional water treatment technologies. Acoustic cavitation as driven by high-frequency ultrasound has been shown to mineralize dilute aqueous solutions of these perfluorinated chemicals. The PFOS and PFOA rate constants have been determined for the various sonochemical reactor configurations and it is observed for both PFOS and PFOA that the optimal acoustic frequency is 354 kHz and that rates increase linearly with increasing power density. Thus, by increasing the applied acoustic power, the degradation rate can be increased. These results are evaluated semi-quantitatively in terms of number of active bubble events per unit time. The results are also compared to the kinetics determined for a pilot-scale sonochemical reactor.
 

Advances in Abiotic Transformation Processes for Micropollutants in Drinking Water and for Sourcewater Protection
1:30 PM-5:10 PM, Tuesday, April 8, 2008 Morial Convention Center -- Rm. 237, Oral

Division of Environmental Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008