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611253 
Journal Article 
Experimental determination of Henry's law constant of perfluorooctanoic acid (PFOA) at 298K by means of an inert-gas stripping method with a helical plate 
Kutsuna, S; Hori, H 
2008 
1 
Atmospheric Environment
ISSN: 1352-2310
EISSN: 1873-2844 
42 
39 
8883-8892 
English 
WOS:000261857600005 
is supplemented by 3986419 : Supplementary materials
The Henry''s law constant (K H) of perfluorooctanoic acid (PFOA, C7F15C(O)OH) was determined at 298K in aqueous sulfuric acid solutions and in aqueous sodium chloride and sulfuric acid mixtures by an inert-gas stripping method in which a helical plate was used to increase the residence time of the gas bubbles in the solutions. The partial pressures of C7F15C(O)OH in the purge gas (P PFOA) were determined by means of Fourier-transform infrared spectroscopy. Time-courses of P PFOA and concentrations of PFOA in the test solutions (C PFOA) differed from those typically obtained by an inert-gas stripping, indicating both the presence of C7F15C(O)OH aggregates, even at low concentrations of C7F15C(O)OH in aqueous sulfuric acid solutions, and the adsorption of gaseous C7F15C(O)OH on the walls of the experimental apparatus. We derived overall gas-to-water partition coefficients (K H′) by simulating the time-courses of P PFOA and C PFOA simultaneously to optimize parameters of the model relating to the partitioning, the aggregation, and the adsorption. The K H′ value for 0.31moldm−3 sulfuric acid solutions at 298K was determined at 3.8±0.1moldm−3 atm−1. From the relationship between K H′ and the ionic strength of aqueous sulfuric acid solutions, the K H values of C7F15C(O)OH at 298K were determined at 9.9±1.5moldm−3 atm−1 for pK a =2.8 and 5.0±0.2moldm−3 atm−1 for pK a =1.3. The pK a value of 1.3 seems to be most probable among the reported three values for C7F15C(O)OH, taking into account dependence of K H′ on... [Copyright 2008 Elsevier] Copyright of Atmospheric Environment is the property of Pergamon Press - An Imprint of Elsevier Science and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts) 
Henry's law; perfluorooctanoic acid; sulfuric acid; fourier transform infrared spectroscopy; partition coefficient (chemistry); simulation models; air pollution monitoring