Chemosphere ( IF 5.778 ) Pub Date : 2020-09-14 , DOI: 10.1016/j.chemosphere.2020.128337 Sang Hyun Kim; Seulki Jeong; Hyeonyong Chung; Kyoungphile Nam
A basic oxygen furnace (BOF) slag was used to stabilize lead (Pb) in a mine waste. Stabilization efficiencies differed depending on the slag contents (i.e., 3, 5, and 10 weight %) and the water contents (i.e., 0.05–5.0 L/kg), varying from 52.2 to 98.0%, and both the slag contents and the water contents positively affected the stabilization efficiency. X-ray photoelectron spectroscopy suggested an evidence that precipitation and adsorption mechanisms were involved. When the contribution of each mechanism was determined, the increase in the BOF slag content mainly increased adsorption mechanism probably because of the increase in the adsorption sties. The increase in the water content, on the other hand, facilitated precipitation mechanism by lowering the ionic strength. Stabilized Pb could be mobilized at redox potential of 20–85 mV due to the reductive dissolution of Fe and Mn oxides. Sequential extraction results demonstrated that the adsorbed Pb became mobilized, and the fraction of exchangeable Pb increased.