Publications by authors named "Etsuko Hayakawa"
Article Synopsis
- Researchers investigated a method to decompose persistent perfluorocarboxylic acids (PFCAs) in water using persulfate ions (S2O8(2-)).
- The process involves photolysis of S2O8(2-), which generates sulfate radicals that effectively break down compounds like perfluorooctanoic acid (PFOA) into fluoride ions and carbon dioxide, with some shorter-chain PFCAs also produced.
- The technique demonstrated a high decomposition efficiency, completely breaking down PFOA at a concentration typical of wastewater in just 4 hours of exposure to a specialized light source.
The decomposition of persistent and bioaccumulative perfluorooctanoic acid (PFOA) in water by UV-visible light irradiation, by H202 with UV-visible light irradiation, and by a tungstic heteropolyacid photocatalyst was examined to develop a technique to counteract stationary sources of PFOA. Direct photolysis proceeded slowly to produce CO2, F-, and short-chain perfluorocarboxylic acids. Compared to the direct photolysis, H2O2 was less effective in PFOA decomposition.
View Article and Find Full Text PDFA rapid and simple method for separating and determining various environmentally harmful perfluorocarboxylic acids and perfluorosulfonates was successfully developed using high- performance liquid chromatography with conductimetric detection, for product and waste management of these compounds at manufacturing and processing sites. Compounds having C(3)-C(8) perfluoroalkyl groups were separated using a Tosoh TSKgel Super-ODS column and a mobile phase consisting of a mixture of methanol and aqueous NaH(2)PO(4) at several mixing ratios. The best detection limits for the compounds ranged from 0.
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