Effect of cationic and anionic surfactants on the sorption and desorption of perfluorooctane sulfonate (PFOS) on natural sediments.
Sorption and desorption of PFOS at water-sediment interfaces were investigated in the presence of a cationic surfactant, cetyltrimethylammonium bromide (CTAB), and an anionic surfactant, sodium dodecylbenzene sulfonate (SDBS). CTAB remarkably enhanced the sorption of PFOS on the sediment. In contrast, the influence of SDBS to the sorption of PFOS was concentration dependent. Two contrasting factors were responsible for the phenomenon. One was the sorption of the surfactant itself to the sediment, which enhanced the sorption of PFOS. The other was the increase in solubility of PFOS caused by the adding of surfactants, which decreased the sorption of PFOS. SDBS had a much lower sorption capacity, but rather strong ability to increase the solubility of PFOS. High levels of SDBS remarkably reduced the sorption of PFOS on the sediment. These results imply that cationic and anionic surfactants may have contrast impacts on the distribution and transport of PFOS in the environment.
Pan
Gang
G
Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, 18 Shuangqing Road, Beijing 100085, China. gpan@rcees.ac.cn
Jia
Chengxia
C
Zhao
Dongye
D
You
Chun
C
Chen
Hao
H
Jiang
Guibin
G
D000327:Adsorption; D017738:Alkanesulfonic Acids / Q000737:chemistry*; D004463:Ecology / Q000379:methods; D004787:Environmental Pollution; D005466:Fluorocarbons / Q000737:chemistry*; D019015:Geologic Sediments / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D012989:Soil Pollutants / Q000737:chemistry*; D013501:Surface-Active Agents / Q000494:pharmacology*
D017738:Alkanesulfonic Acids; D005466:Fluorocarbons; D012989:Soil Pollutants; D013501:Surface-Active Agents; C076994:perfluorooctane sulfonic acid