天然膨润土吸附水中Pb^(2+)的影响因素和动力学规律

Affecting Factors and Kinetics of Adsorption of Pb^(2+) from Aqueous Solutions by Natural Bentonite

通过静态实验探讨了膨润土用量、Pb2+初始质量浓度、初始pH值、温度等对天然膨润土吸附水中Pb2+的影响和其吸附动力学规律。结果表明,随着温度或Pb2+初始质量浓度的增加,天然膨润土对Pb2+的吸附量增加;但随着膨润土用量的增加,吸附量减小。在pH值为3～7时随着pH值的增加,吸附量增加。此外,天然膨润土吸附Pb2+的的动力学规律符合Lagergren准二级反应模型,并且吸附速度较快,吸附60min后基本达到平衡。

The influences of bentonite amounts, initialPb^2＋ concentration, initial pH and temperatures on the adsorption of Pb^2＋ from aqueous solutions by natural bentonite （NB） and its adsorption kinetics were investigated through batch experiments. The results indicated that the adsorption capacity was increased with the increasing of temperature or initial Pb^2＋ concentration, but decreased with the increasing of NB amounts. Increasing pH would increase adsorption capacity when pH was between 3 and 7. Moreover, the adsorption kinetics followed pseudo -second order reaction models under the experiment conditions. The results also indicated that the adsorption rate of Pb^2＋ onto NB was satisfactory, and the adsorption processes approximately reached equilibrium in 60 min.