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利用双离子选择电极法研究了搅拌速度和土／水比对Ｐｂ２＋和Ｃｕ２＋在可变电荷土壤和矿物表面的吸附动力学的影响。结果表明：当搅拌器上所加电压为０—１００Ｖ时，Ｐｂ２＋和Ｃｕ２＋的吸附转化率随电压的增加而增大；当电压＞１００Ｖ后，吸附转化率不再变化。这表明在＜１００Ｖ的低速搅拌下，外扩散是Ｐｂ２＋和Ｃｕ２＋吸附反应的速率控制步骤，而在＞１００Ｖ的高速搅拌下，吸附步骤为速率控制步骤。Ｐｂ２＋和Ｃｕ２＋的吸附量随土／水比的增大而减小。在二级动力学方程中，最大吸附量Ｘｍ随土／水比的增大而减小，动力学常数Ｋ随土／水比的增加而增大。Ｐｂ２＋的Ｘｍ和水／土比（ｍｌ／ｇ）呈极显著正相关。
The effect of stirring rate and soil / water ratio on the adsorption kinetics of Pb2 + and Cu2 + on the surface of variable charge soils and minerals was studied by dual ion selective electrode method. The results show that when the voltage applied on the stirrer is 0-100V, the adsorption conversion rate of Pb2 + and Cu2 + increases with the increase of voltage; when the voltage is more than 100V, the conversion of adsorption does not change any more. This indicates that out-diffusion is a rate-controlling step for the adsorption reaction of Pb2 + and Cu2 + at low stirring speed <100V, whereas the rate-controlling step is the adsorption step at high-speed stirring> 100V. The adsorption amount of Pb2 + and Cu2 + decreases with the increase of soil / water ratio. In the second-order kinetic equation, the maximum adsorption capacity Xm decreases with the increase of soil-water ratio, and the kinetic constant K increases with the increase of soil-water ratio. There was a significant positive correlation between Xm and water / soil ratio (ml / g) of Pb2 +.