A pilot scale system utilizing boron-doped diamond perforated plates for the destruction of PFOA

Session: Poster Session

Mary Ensch, Michigan State University , [email protected]
Michael Becker, Fraunhofer USA, Inc. Center for Coatings and Diamond Technologies , [email protected]
Thomas Schuelke, Michigan Statee University / Fraunhofer USA, Inc. Center for Coatings and Diamond Technologies, [email protected]
Cory Rusinek, Fraunhofer USA, Inc. Center for Coatings and Diamond Technologies, [email protected]

Abstract

Perfluorooctanoic acid (PFOA) is a man-made surfactant that is persistent in the environment. Although its manufacturing has been phased out of industry, it has been detected around the world at concentrations well above the miniscule levels that have shown toxic health effects in humans and animals. Electrochemical oxidation has shown promise in degrading this compound in wastewater sources using various electrode materials including boron-doped diamond (BDD) at the bench-scale. This study takes this investigation a step further and explores the possibility of advancing the degradation process to large-scale. A 2 ppm solution of PFOA in 50 mM sodium sulfate with a total volume of 10 L was used. The combined active anode surface area was 33.6 cm² with an applied current density of 200 mA/cm². Temperature, pH, and voltage were recorded throughout the duration of the 8 hour test. Samples were removed from the systems tank at set time intervals and analyzed using a fluoride ion selective electrode (ISE) and liquid chromatography mass spectroscopy (LC-MS). At the end of the test, only 0.25% of the original PFOA concentration remained. Examination into the fluoride mass balance and generation of shorter chains gave further insight into this methods ability to be successful.