| Organic mineral reagent has become another kind of important pollutions besides the heavy metal pollutants in the Mining area. Organic mineral reagent itself is toxic and it can complexs heavy metal in soil,and change theit migration process,and prolongs theit migration distances, which are possible to form more serious combined pollution. Therefore, it is very improtant for the pollution control of mineral reagents-heavy metals combined pollution to study the behavior of the mineral reagents in soil and rules of adsorption of heavy metals in soil with mineral reagents.The isothermal and static adsorption experiment is used to study xanthate adsorption on rice soil, vegetable garden soil and limestone soil and adsorption and desorption of Pb on soil with xanthate. Time, initial concentration of xanthate and Pb, pH.Kinetics equation and the adsorption isotherm are used to analysis in the study. Results show that in 144h, the removal rate of each treatment on the xanthate:vegetable garden soil (66.64%)> rice soil (56.54%)> without soil (33.26%)> limestone soil (23.42%). That the lower the soil pH value, the higher the organic matter content are conducive to the removal of xanthate, and vice versa on the removal of xanthate from inhibition. Adding xanthate, the adsorption of Pb on the three soils is still well with the second order kinetic equation, the order of adsorption capacity of limestone soil (24.65mg·g-1)> rice soil (10.97 mg·g-1)> vegetable garden soil (7.885 mg·g-1), compared to the rate of decline of treament without xanthate the order of xanthate rice soil (22.74%)> vegetable garden soil (15.76%)> limestone soil (3.69%); Meanwhile, Freundlich is more appropriate than the Langmuir to describe the adsorption in three soils.Adding xanthate,adsorption on the maximum amount of Pb followed by limestone soil (40.50mg·g-1)> rice soil (12.51 mg·g-1)> vegetable garden soil (11.16mg·g-1), compared to the rate of decline of treament without xanthate followed by vegetable garden soil (32.54%)> rice soil (29.88%)> limestone soil (12.63%).It can be seen greatest impact on the vegetable garden soil with adding xanthate. This was mainly due to xanthate in the appropriate conditions,complexs heavy metal generating hydrophobic insoluble Potassium ethyl xanthate which gathered on the solution surface,that reducing the adsorption of Pb content in the soils. The reason is that inference xanthate in the appropriate conditions, form complexes with Pb lead xanthate gather in reducing Pb in soil solution on the surface of the adsorption. Xanthate in alkaline (pH=7～8) more easily and lead the formation of lead xanthate, resulting in the adsorption capacity of soil Pb decreased significantly. Xanthate and the initial concentration of Pb on the formation of xanthate proportional to the amount of lead. |
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