Authors: Yuchi Lee Shanglien Lo Jeff Kuo Chinghong Hsieh
Publish Date: 2011/11/04
Volume: 6, Issue: 1, Pages: 17-25
Abstract
Microwavehydrothermal treatment of persistent and bioaccumulative perfluorooctanoic acid PFOA in water with persulfate S2O 8 2− has been found effective However applications of this process to effectively remediate PFOA pollution require a better understanding on freeradical scavenging reactions that also take place The objectives of this study were to investigate the effects of pH pH = 25 66 88 and 105 chloride concentrations 001–015 mol·L−1 and temperature 60°C 90°C and 130°C on persulfate oxidation of PFOA under microwave irradiation Maximum PFOA degradation occurred at pH 25 while little or no degradation at pH 105 Lowering system pH resulted in an increase in PFOA degradation rate Both high pH and chloride concentrations would result in more scavenging of sulfate free radicals and slow down PFOA degradation When chloride concentrations were less than 004 mol·L−1 at 90°C and 006 mol·L−1 at 60°C presence of chloride ions had insignificant impacts on PFOA degradation However beyond these concentration levels PFOA degradation rates reduced significantly with an increase in chloride concentrations especially under the higher temperature
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