Effect of solution chemistry and aggregation on adsorption of perfluorooctanesulphonate (PFOS) to nano-sized alumina.

The interaction of pollutants with nanomaterials has attracted attention due to the extensive application of nanomaterials. In this study, the adsorption behavior of PFOS on nano-alumina with different shapes was investigated. First, the adsorption isotherms and kinetics of PFOS on alumina nanoparticles (NPs) and nanowires (NWs) were measured to calculate thermodynamic parameters. The effects of solution chemistry (e.g., pH, ionic strength, and the presence of humic acid) on adsorption were further studied. The different aggregation behavior of alumina NPs and NWs were the critical factor for PFOS adsorption, as demonstrated through dynamic light scattering (DLS) experiments. This study is the first to investigate the aggregation effects on PFOS adsorption on nanomaterials and the results should be useful in identifying the important roles of shape and aggregation of nanomaterials on the fate of organic pollutants in the environment.