Relationship Between Reaction Rate of Perfluorocarboxylic Acid Decomposition at a Plasma–Liquid Interface and Adsorbed Amount. Issue 2 (July 2014)

• Record Type: Journal Article
• Authors: Matsuya, Yuriko; Takeuchi, Nozomi; Yasuoka, Koichi
• Is Part Of: Electrical engineering in Japan. Volume 188:Issue 2(2014)
• Page Start: 1
• Page End: 8
• Publication Date: 2014-07
• Subjects: Electrical engineering -- Periodicals; 621.30952
• DOI: 10.1002/eej.22526
• Languages: English
• ISSNs: 0424-7760

Abstract

<abstract abstract-type="main"> <title>SUMMARY</title> <p>Perfluorooctanoic acid (PFOA: C<sub>7</sub>F<sub>15</sub>COOH) in water is effectively decomposed by plasma generated at a gas–liquid interface. During the decomposition of PFOA, perfluorocarboxylic acids (PFCAs: <alternatives><inline-graphic mimetype="image" xlink:href="ark:/27927/pgg5f3dq635" xlink:type="simple" xmlns:xlink="http://www.w3.org/1999/xlink" /><mml:math display="inline" altimg="urn:x-wiley:04247760:eej22526:equation:eej22526-math-0001" overflow="scroll" xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:mrow><mml:msub><mml:mi mathvariant="normal">C</mml:mi><mml:mi>n</mml:mi></mml:msub><mml:msub><mml:mi mathvariant="normal">F</mml:mi><mml:mrow><mml:mn>2</mml:mn><mml:mi>n</mml:mi><mml:mo>+</mml:mo><mml:mn>1</mml:mn></mml:mrow></mml:msub><mml:mi> COOH </mml:mi></mml:mrow></mml:math></alternatives>) with shorter carbon chains (<italic>n</italic> = 1–6) are generated as by‐products. Since these PFCAs are surfactants, they are adsorb onto the gas–liquid interface and show high surface concentrations. This study investigated the relationship between the adsorbed amount of PFCA and the rate of decomposition by a direct current plasma. The adsorbed amount of PFCA at the gas–liquid interface increased as the length of the carbon chain increased, resulting in a higher rate of decomposition. However, the reaction rate reached saturation at a certain adsorption amount, depending on the discharge current.</p> </abstract>