Chemical elution treatment of synthetic diamond production wastewater contaminated soil

Abstract

The optimal removal conditions of heavy metal Coand Nicomposite contaminated soil were studied by the method of oscillating elution. The removal effects of different eluents on Coand Niat different concentrations were discussed.The results showed that the removal efficiency of citric acid with the concentration of 0.2mol•L-1was the best,and the removal rates of Coand Niwere 73.40% and 73.03%.On this basis, the effects of solid-liquid ratio, pH and elution time on the elution effect were investigated.The resultsshow that the trend of the two heavy metals affected by the above three factors is about the same. As the solid-liquid ratio decreases, the elution effect gradually increases, but the growth range is different.As the pH increases, the elution effect of the two heavy metals decreases. In addition, the removal rates of the two heavy metals show a trend of rising first, then stabilizing, and then continuing to rise. Considering economic factors, time cost and treatment effect, the best elution conditions aresolid-liquid ratio of 1: 20, pH value of 2 and elution time of 6 h.