选用具有高比表面、强吸附能力的二氧化硅纳米空心微球作吸附剂，对Pb2+、Cu2+及Cr3+的吸附性能进行测试。利用 Langmuir 线性方程对吸附平衡数据进行拟合。结果表明：二氧化硅纳米空心微球对重金属离子具有较高的饱和吸附量，分别为1.256、0.681、0.563 mmol/g。饱和吸附量与重金属离子的共价指数及电荷密度有很强的相关性，随着共价指数增加或电荷密度的降低，饱和吸附量增大；吸附常数与重金属离子电场强度(有效核电荷数)有关，随着有效核电荷数的增加，吸附常数增大。此吸附过程具有化学吸附特征，再生的吸附剂可以重复使用。% The adsorbability of hollow SiO2 nanospheres of high adsorption capacity and large specific surface area for Pb2+, Cu2+, and Cr3+ions was investigated. The absorbtion equilibrium data were fitted by Langmuir linear equation. The results show that hollow SiO2 nanospheres have high adsorption capacity for heavy metal ions, the adsorption capacities for Pb2+, Cu2+and Cr3+ions are 1.256, 0.681, and 0.563 mmol/g, respectively. As the fitting data shown, there is a strong correlation between the adsorption capacity and ion characteristics (covalent index and charge density). The adsorption capacity increases with the increase in covalent index or decrease in charge density. The adsorption constant is related to electric field intensity of ion (effective nuclear charge), and the adsorption constant increases with the increase in effective nuclear charge of ion. This adsorption process should belong to chemisorption. The regenerated adsorbent can be reused many times.
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