College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, PR China.
College of Marine Life Sciences, Ocean University of China, 5 Yushan Road, Qingdao 266003, PR China.
Carbohydr Polym. 2017 Sep 15;172:28-39. doi: 10.1016/j.carbpol.2017.05.039. Epub 2017 May 12.
A novel adsorbent, composed of poly(maleic acid)-grafted cross-linked chitosan microspheres (PMACCMs), was prepared via cross-linking with glutaraldehyde and modification by grafting maleic acid. FTIR, zeta potential, elemental analysis, C NMR, DTG, laser particle size analysis, SEM, and BET methods were applied to characterize PMACCMs, exhibiting a successful fabrication, good thermostability, and well-defined surface microstructure beneficial to Cd(II) adsorption. The effects of pH, contact time, and initial concentration on Cd(II) adsorption were also investigated, and the maximum adsorption capacity was 39.2mgg, indicating a great improvement as compared with that (14.5mgg) of cross-linked chitosan microspheres. The experimental data were well fitted with pseudo-second-order kinetic and Langmuir isotherm models. Five-cycle reusability tests demonstrated PMACCMs could be repeatedly used with a small adsorption capacity loss (<15%). Additionally, the adsorption mechanism was proposed. All the results confirmed that PMACCMs, which presented outstanding adsorption capability and reusability, could be a good candidate for wastewater purification.
一种新型吸附剂，由聚（马来酸）接枝交联壳聚糖微球（PMACCMs）组成，通过与戊二醛交联和接枝马来酸修饰制备。采用傅里叶变换红外光谱（FTIR）、zeta 电位、元素分析、C 核磁共振（C NMR）、热重分析（DTG）、激光粒度分析、扫描电子显微镜（SEM）和 BET 方法对 PMACCMs 进行了表征，结果表明成功制备了 PMACCMs，具有良好的热稳定性和明确的表面微观结构，有利于 Cd(II)的吸附。还考察了 pH 值、接触时间和初始浓度对 Cd(II)吸附的影响，最大吸附容量为 39.2mgg，与交联壳聚糖微球（14.5mgg）相比有了很大的提高。实验数据与准二级动力学和 Langmuir 等温线模型拟合良好。五次循环重复使用测试表明，PMACCMs 可以重复使用，且吸附容量损失较小（<15%）。此外，还提出了吸附机制。所有结果均证实，PMACCMs 具有出色的吸附能力和可重复使用性，可作为废水净化的良好候选材料。
