Remediating lead, zinc, cadmium and arsenic contaminated steel smelting site with hydrochloric acid and sodium hydroxide

摘要

A-two step soil washing experiment was conducted to search an effective washing technique for the remediation of the contaminated soil from a steel smelting site. Our results indicated that 0.5M of hydrochloric acid alone could reduce soil cadmium concentration to lower than 1 mg kg~(-1), 1M of hydrochloric acid alone could reduce soil lead concentration to lower than 140 mg kg~(-1), 2M of hydrochloric acid combined with 0.2M of sodium hydroxide could reduce soil zinc concentration to lower than 200 mg kg~(-1) and reduce soil arsenic concentration to lower than 20 mg kg~(-1), the washed soil could be safely reused according to the national exhibition land quality standards of grade A.