采用静态平衡实验，研究了不同pH值、温度和初始钒浓度条件下，钒在石煤提钒区水稻土中的吸附?解吸特性．结果表明，不同钒含量水稻土对钒的吸附等温线均符合Langmuir方程和Freundlich方程，Elovich方程和双常数方程可较好地描述水稻土对钒的吸附动力学过程．水稻土钒的吸附?解吸量随温度和溶液初始钒浓度增加而增加，随pH升高而减少．低钒含量土壤（140 mg·kg－1）对钒的最大吸附量为2813 mg·kg－1，高于高钒含量土壤（650 mg·kg－1）的最大吸附量（2038 mg·kg－1）．土壤钒的解吸量随吸附量的增加而增大，解吸率为10．7％—29．3％，两者呈幂函数关系．酸性条件和较高温度下水稻土吸附的钒较易解吸，进入环境的风险较高，因此，我国石煤提钒区外源钒进入水稻土壤后其潜在迁移风险值得关注．
Adsorption?desorption characteristics of vanadium ( V ) on paddy soils collected from the vicinity of V?containing stone coal smelting area, were studied by batch experiments under conditions of different pH values, temperatures and initial V concentrations in solution. The results showed that the adsorption isotherms of V on two paddy soils were well described by both Langmuir and Freundlich equation, and the adsorption kinetic fitted well with Elovich equation and double constant equation. The adsorption and desorption amount of V on paddy soils increased with the increase of temperature, initial V concentration, and the decrease of pH value, respectively. The maximum adsorption amount of V on soil was 2813 mg·kg-1 , with low V content ( 140 mg·kg-1 ) , and 2038 mg·kg-1 on soil with high V content ( 650 mg·kg-1 ) . The V desorption amount on paddy soils increased with increasing V desorption amount, and the adsorption rate was in the range of 10.7%—29.3%. The relationship between adsorption and desorption amount of V could be described by power function equation.Since V adsorbed by paddy soil can be easily released in acid condition and high temperature, attention should be paid to the potential mobilization risk of exogenous V entering into paddy soils from the V?containing stone coal smelting area in south China.
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