Immobilization of Nitro Explosives and Metals in Biochar-Amended Soils and Mine Tailings

摘要

Results from TCLP and HPCD extraction showed that approximately 55-95% of explosives were released from the contaminated soils. This indicates that a substantial amount of explosives in contaminated soils are mobile. With the addition of biochar, extracted concentrations of the explosives were reduced to less than 10% of initial concentrations in 10 days. According to results from a Korean waste leaching method, TCLP, and DTPA extraction, addition of biochar to mine tailings also significantly reduced extractability and bioavailability of metals. Increasing the amount of biochar can decrease the extractability of the explosives and metals. Considering metal concentrations in sequential extraction, metals in labile phases can be effectively immobilized by addition of biochar. Our results suggest that biochar can be an effective sorbent to immobilize the explosives and metals from contaminated soils and mine tailings.