Key Laboratory for Attapulgite Science and Applied Technology of Jiangsu Province, Huaiyin Institute of Technology, Huaian, People's Republic of China.
Environ Technol. 2011 Apr;32(5-6):523-31. doi: 10.1080/09593330.2010.504748.
A series of novel granular chitosan-g-poly(acrylic acid)/attapulgite/sodium humate (CTS-g-PAA/APT/SH) composite hydrogels were successfully prepared by one-step free radical graft polymerization and applied as adsorbents for the removal of Pb(II) from aqueous solution. The effects of adsorbent composition (including the contents of APT, SH and CTS) on adsorption capacity and adsorption rate were investigated in detail. Results from kinetic experiments showed that the rate of Pb(II) adsorption on the composite hydrogels was quite fast, that more than 90% of the equilibrium adsorption capacity occurs within two minutes and that the adsorption equilibrium could be achieved within 10 minutes. The adsorption kinetics fit well with the pseudo-second order equation. The introduced SH is helpful for both adsorption capacity and adsorption rate. The -COOH and -COO of PAA, -NH2 of CTS, Ph-O and -COO- of SH, as well as cation exchange and Si-OH of APT, participate in adsorption of Pb(II). The synergistic effect of these groups is responsible for the high adsorption capacity and rate.
一系列新型颗粒状壳聚糖-g-聚丙烯酸/凹凸棒土/腐植酸钠（CTS-g-PAA/APT/SH）复合水凝胶通过一步自由基接枝聚合成功制备，并用作从水溶液中去除 Pb(II) 的吸附剂。详细研究了吸附剂组成（包括 APT、SH 和 CTS 的含量）对吸附容量和吸附速率的影响。动力学实验结果表明，复合水凝胶对 Pb(II) 的吸附速率相当快，在两分钟内达到超过 90%的平衡吸附容量，在 10 分钟内达到吸附平衡。吸附动力学很好地符合拟二级方程。引入的 SH 有助于提高吸附容量和吸附速率。PAA 的-COOH 和-COO-、CTS 的-NH2、SH 的 Ph-O 和-COO-以及 APT 的阳离子交换和 Si-OH 参与了 Pb(II)的吸附。这些基团的协同作用是高吸附容量和速率的原因。
