Pilot-Scale Decontamination of Soil Polluted with As, Cr, Cu, PCP, and PCDDF by Attrition and Alkaline Leaching

AbstractRecently, an efficient and promising process was developed to allow the removal of As, Cr, Cu, pentachlorophenol (PCP), and polychlorodibenzo-dioxins and furans (PCDDF) from soil using alkaline leaching. The present study evaluates the performance and the robustness of this decontamination process for the treatment of four different polluted soils by attrition and alkaline leaching at a pilot scale. The attrition process carried out on the coarse fraction (>0.125 mm) allowed the removal of 24–42% of As, 0–13% of Cr, 23–46% of Cu, 0–85% of PCP, and 17–64% of PCDDF from the different contaminated soils. Removal yields of 87–95% of As, 50–72% of Cr, 73–84% of Cu, 52–100% of PCP, and 27–73% of PCDDF were obtained after three leaching steps ([NaOH]=1 M; [Cocamydopropylbetaine—BW]=3% (w/w); t=2 h; pulp density [PD]=10% [w/v]) conducted on the fine fraction (