Institute of Environment Engineering and Science, School of Chemistry and Material Science, Key Laboratory for Catalysis and Materials Science of the State Ethnic Affairs Commissions & Ministry of Education, South Central University for Nationalties, Wuhan 430074, China.
Bioresour Technol. 2010 Jul;101(14):5175-9. doi: 10.1016/j.biortech.2010.02.027. Epub 2010 Mar 3.
In this study, the natural and modified rice husk were tested to remove Cd(II) ions from water. The modified rice husk was prepared by being treated with alkali. The results showed the Cd(II) adsorption capacity was 73.96, 125.94 mg/g, respectively, for the natural and modified rice husk. The modified rice husk had faster kinetics and higher adsorption capacities than the natural rice husk, which can be attributed to the surface structural changes of the material. Equilibrium adsorption data are more consistent with the Langmuir isotherm equation than with the Freundlich equation. The Cd(II) adsorption on the two adsorbents tends to increase with the increase of pH. The optimum pH for Cd(II) adsorption is 6.5. Both pseudo-first-order and pseudo-second-order equations were able to describe properly the kinetics of Cd(II) adsorption. The desorbability of Cd(II) is about 95.8-99.1% by 0.1M HCl solution.
在这项研究中，天然稻壳和改性稻壳被用于从水中去除 Cd(II)离子。改性稻壳是通过用碱处理制备的。结果表明，天然稻壳和改性稻壳对 Cd(II)的吸附容量分别为 73.96、125.94mg/g。与天然稻壳相比，改性稻壳具有更快的动力学和更高的吸附容量，这可以归因于材料表面结构的变化。平衡吸附数据更符合 Langmuir 等温方程，而不是 Freundlich 方程。Cd(II)在两种吸附剂上的吸附随 pH 的增加而增加。Cd(II)吸附的最佳 pH 值为 6.5。准一级和准二级方程都能很好地描述 Cd(II)吸附的动力学。用 0.1M HCl 溶液解吸 Cd(II)的解吸率约为 95.8-99.1%。
