Efficient Decomposition of Perfluorinated Compounds In a High Photon Flux UV/sulfite system

Perfluorinated compounds (PFCs) have attracted increasing attention due to their global distribution, high chemical stability and persistence. Hydrated electron (eaq-) is a strong reductant, and is reported promising for recalcitrant organic pollutants decomposition. In this study, eaq- based photodecompositon of several PFCs in a high photon flux UV/sulfite system was investigated. Perfluorosulfonic acids (PFSAs) and perfluorocarboxylic acids (PFCAs) decomposition in the studied system were 1~2 orders of magnitude faster than that in previously studied BDD electrooxidation and UV/KI photoreduction systems. Kinetic study revealed the observed rate constant (Kobs) of both PFSAs and PFCAs increased with the increase of carbon chain length. In mixed PFCAs or PFSAs solution, decomposition of each PFCAs or PFSAs was suppressed due to the competition of eaq-.