Batch Sorption of PFOS onto Local Soils in Japan

Perfluorooctane sulfonate (PFOS) contamination in groundwater and soil has become a global problem. Although evaluating the sorption performance of soils against PFOS is essential for considering the proper countermeasures, limited research has been conducted in Japan. This study investigated the sorption kinetics and isotherms using local Japanese soils. In addition, the relation between the sorbed amount of PFOS and the basic properties of local Japanese soils was evaluated. The results of sorption kinetics were well fitted to the pseudo-first-order or pseudo-second-order models, except for the case using silica sand at the initial PFOS concentration of 1 mg/L. Sorption equilibrium against PFOS was achieved after approximately 24 hours. The Langmuir model can well describe PFOS sorption isotherms for four soils. A positive correlation was obtained between sorbed amount and soil properties such as Organic Carbon (OC), fines content, and aluminium oxide (Al2O3) content. Results implied that the soil properties should be carefully examined when we discuss the sorption performance against PFOS. © 2024 The Society of Materials Science, Japan.