Ultrasonic extraction technique was used to extract perflurooctanoic acid (PFOA) and its salts from fluro-paints.The extract was quantified after filtration and concentration by gas chromatography-mass (GC-MS) method ...Ultrasonic extraction technique was used to extract perflurooctanoic acid (PFOA) and its salts from fluro-paints.The extract was quantified after filtration and concentration by gas chromatography-mass (GC-MS) method using perflurodecanoic acid methyl ester as an internal standard.The GC-MS conditions were: HP-Innowax capillary column; oven temperature,50℃(5 min)30℃/min240℃(5 min); splittless mode; injection volume,1μL; negative chemical ion source,reacting gas,CH4,20%; select ion scan mode (SIM);Line range was 1.0-1.0×105 μg/L; the correlation coefficient was 0.999; the low limit of detection (LOD) was 0.1 μg/L.The RSD was 4.24% and 3.58% respectively for low and high concentration of PFOA,and the average recovery was between 86%-111%.展开更多
Electron beam(EB) degradation of perfluorooctanoic acid(PFOA) and perfluorooctane sulfonate(PFOS) in aqueous solutions was studied. It suggested that PFOA and PFOS degradation followed the pseudo-firstorder kinetics, ...Electron beam(EB) degradation of perfluorooctanoic acid(PFOA) and perfluorooctane sulfonate(PFOS) in aqueous solutions was studied. It suggested that PFOA and PFOS degradation followed the pseudo-firstorder kinetics, and degradation rates increased with increasing initial p H. Radical scavengers' experiments indicated that hydrated electron and hydrogen radical were important in the electron beam degradation of PFOA and PFOS, especially hydrated electron. The decomposition efficiencies were 95.7% for PFOA and 85.9% for PFOS, by EB irradiation in an anoxic alkaline solution(p H = 13).The potential degradation pathways of PFOA and PFOS by electron beam irradiation through defluorination and the removal of CH_2 unit were proposed.展开更多
文摘Ultrasonic extraction technique was used to extract perflurooctanoic acid (PFOA) and its salts from fluro-paints.The extract was quantified after filtration and concentration by gas chromatography-mass (GC-MS) method using perflurodecanoic acid methyl ester as an internal standard.The GC-MS conditions were: HP-Innowax capillary column; oven temperature,50℃(5 min)30℃/min240℃(5 min); splittless mode; injection volume,1μL; negative chemical ion source,reacting gas,CH4,20%; select ion scan mode (SIM);Line range was 1.0-1.0×105 μg/L; the correlation coefficient was 0.999; the low limit of detection (LOD) was 0.1 μg/L.The RSD was 4.24% and 3.58% respectively for low and high concentration of PFOA,and the average recovery was between 86%-111%.
基金supported by the National Natural Science Foundation of China(Nos.11675098,41430644,41473090,41373098)Program for Changjiang Scholars and Innovative Research Team in University(No.IRT13078)
文摘Electron beam(EB) degradation of perfluorooctanoic acid(PFOA) and perfluorooctane sulfonate(PFOS) in aqueous solutions was studied. It suggested that PFOA and PFOS degradation followed the pseudo-firstorder kinetics, and degradation rates increased with increasing initial p H. Radical scavengers' experiments indicated that hydrated electron and hydrogen radical were important in the electron beam degradation of PFOA and PFOS, especially hydrated electron. The decomposition efficiencies were 95.7% for PFOA and 85.9% for PFOS, by EB irradiation in an anoxic alkaline solution(p H = 13).The potential degradation pathways of PFOA and PFOS by electron beam irradiation through defluorination and the removal of CH_2 unit were proposed.