Abstract:Elution experiment of Cd contaminated soil around a mine was carried out using Ca(H2PO4)2 as raw material to prepare leaching agent. The contents of Ca2+ and total phosphorus in eluant and elution effect under different preparation conditions were analyzed. Based on that, the effects of L/S and washing time on remediation effect were further analyzed. The washing process was fitted dynamically, and the morphological distributions of Cd in soil before and after elution were analyzed. The results show that contents of Ca2+ and total phosphorus in eluant are positively correlated with dosage of Ca(H2PO4)2, and the contents of Ca2+ and total phosphorus and pH value of eluantt prepared without heating are higher. The elution effect is the best when the eluant prepared by mixing 0.07mol of Ca(H2PO4)2 with deionized water for heating, tL/S is 5, and elution time is 3 hours. The removal rate of Cd in soil can reach 70.83%. Elovich equation fits the kinetic process well, and the desorption process is heterogeneous diffusion process. After elution, the extracted form of weak acid and reducible Cd can be effectively removed. Elution remediation method is feasible and can provide a new idea for removing Cd from soil