Adsorption of radioactive cobalt(II) in the groundwater-soil systems surrounding the effluent pipeline of a proposed NPP in China

Radioactive cobalt release poses concerns since the attention to radiation safety. In this work, soil and groundwater sampled from the surroundings of the long-distance pipeline of a proposed nuclear power plant were used to assess radiation safety by studying Co(II) adsorption. The Freundlich and Langmuir models fitted the experimental data well. The results indicated that Co adsorption was an entropy-driven, spontaneous, endothermic and chemical process. The adsorption mechanism was mainly the inner-sphere complexation, and CoSO 4 (aq) contributed to the partially reversible occurrence. This study provided fundamental information about the environmental behaviours and adsorption mechanism of radioactive Co(II) surrounding the effluent pipeline. Graphical abstract