The Study Of Chelating Agent Leaching Experimental To The As And Sb In The Soil Pollutants

The economic development and prosperity, not only brings to china improvement of living standards, but also associated with water, air and soil pollution.Soil pollution not only threaten food security not, it also bring new challenges for the dependency problem.Therefore,the problem of cultivated land pollution should be solved quickly.The technology of chelating agent recovery is a new repair technology to soil pollution.It not only to the environment pollution effect little, also to the soil heavy metal pollution area has a good application prospect.This article selects the lotion of tartaric acid, malic acid, EDTA. Respectively of controlling the eluent of concentration, leaching time,pH value.To study the As and Sb in the condition of soil leaching effect.By the method of BCR extraction,study the changes in the form of the As and Sb content in soil, drench lotion on the As and Sb leaching effect and mechanism.The research shows that, the concentration of the spray lotion had a greater influence on the leaching rate to the As and Sb in the soil.With the increase of concentration, tartaric acid, malic acid, EDTA for antimony arsenic leaching rate also gradually increased, tartaric acid, malic acid leaching of antimony effect is superior to the effect of leaching of arsenic;the effect of EDTA on leaching of arsenic is better than the effect of leaching of antimony.When spray detergent solution of different pH,under the condition of partial acid,tartaric acid or malic acid can leaching more of arsenic, antimony;in the alkaline conditions,they are leaching rate is poorer to the As and Sb;tartaric acid, malic acid leaching rate showed a trend of gradually reduce with the pH become higher; the change of EDTA solution pH,it has little effect for the leaching efficiency to As and Sb.The main reason is that the As and Sb functionalcomplex ions with EDTA is stronger and stability.Concentrations of 10 tendency tartaric acid in pH=3.28 solution for Sb and As,the removal respectively rate of is15.8% and 6.5%;when pH=11.71,it reduced to 4.3% and 4.12%. Concentrations of 10 tendency malic acid solution at pH=3.51,the removal rate of As is 12.10%, in the pH=12.16,it reduced to 3.89%. Therefore, tartaric acid, malic acid solution of pH plays an important role to the As and Sb in the soil leaching effect.Study shows that the distribution of BCR extraction method for tartaric acid,malic acid, EDTA three spray detergent solution leaching of arsenic, antimony heavy metal mainly weak acid extraction, but it has low rate for the oxidation state and state residue; drench lotion is preferred in the process of leaching to relatively easy to release the weak acid extraction condition of the soil heavy metals,but when the weak acid extraction state arsenic antimony content in the soil is small, the can also continue to square one for leaching of heavy metals.By Elovich equation, the double constant equation and first order kinetics equation fitting of the experimental results,it can be concluded that the spray detergent solution for the soil arsenic, antimony heavy metal leaching action between mainly diffusion or heterogeneous diffusion.