Method for preparing and recycling high-concentration antimony and arsenic polluted soil composite eluting agent

The invention provides a preparation and recycling method of a composite eluting agent for high-concentration antimony and arsenic contaminated soil, and belongs to the technical field of heavy metal contaminated soil remediation, the composite eluting agent comprises the following raw materials: oxalic acid, ascorbic acid and hypophosphorous acid, the mass ratio of oxalic acid to ascorbic acid to hypophosphorous acid is (2-10): 2: 1, the concentration of oxalic acid is 0.1-0.5 mol/L, the concentration of ascorbic acid is 0.1 mol/L, and the concentration of hypophosphorous acid is 0.05 mol/L. According to the composite eluting agent disclosed by the invention, the chelating effect of oxalic acid and the reduction effect of ascorbic acid and hypophosphorous acid are utilized to synergistically promote stable structure dissolution of iron-aluminum oxide binding state antimony and arsenic in soil, so that the antimony and arsenic eluting efficiency is improved, and the goal of restoring antimony ...