Gopalakannan Venkatrajan, Viswanathan Natrayasamy
Department of Chemistry, Velammal College of Engineering and Technology, Madurai - 625 009, Tamilnadu, India.
Department of Chemistry, Anna University, University College of Engineering - Dindigul, Dindigul - 624 622, Tamilnadu, India.
Int J Biol Macromol. 2015 Jan;72:862-7. doi: 10.1016/j.ijbiomac.2014.09.024. Epub 2014 Sep 23.
Recently magnetic bio-composites have attracted the attention of scientists because of their unique characteristics like selectivity and high sorption capacity. In the present study, Fe3O4@Alg-Ce magnetic composite beads were developed by incorporating Fe3O4 particles onto alginate (Alg) biopolymer followed by cross-linking with Ce(3+) ions. The synthesized magnetic beads were characterized using FTIR and SEM with EDAX analysis and utilized for chromium (VI) removal in batch mode. A comparative adsorption performance of Fe3O4 particles, calcium alginate (CaAlg) composite and Fe3O4@Alg-Ce magnetic hybrid beads was made. The magnetic alginate beads possess an enhanced SC of 14.29 mg/g than CaAlg composite and Fe3O4 particles which possess SC of 9.45 and 9.72 mg/g respectively. The various sorption influencing parameters like contact time, pH, challenger anions, initial chromium concentration and temperature were optimized. The adsorption process was explained using Freundlich and Langmuir isotherms. The sorption kinetics was fitted well with the pseudo second order and intra particle diffusion model. The calculated thermodynamic parameters indicate the nature of chromium sorption is spontaneous and endothermic.
近年来，磁性生物复合材料因其选择性和高吸附容量等独特特性而吸引了科学家们的关注。在本研究中，通过将Fe3O4颗粒掺入藻酸盐（Alg）生物聚合物中，然后与Ce(3+)离子交联，制备了Fe3O4@Alg-Ce磁性复合珠。使用傅里叶变换红外光谱（FTIR）、扫描电子显微镜（SEM）和能谱分析（EDAX）对合成的磁性珠进行了表征，并将其用于分批模式下铬（VI）的去除。对Fe3O4颗粒、海藻酸钙（CaAlg）复合材料和Fe3O4@Alg-Ce磁性混合珠的吸附性能进行了比较。磁性藻酸盐珠的吸附容量（SC）为14.29 mg/g，高于CaAlg复合材料和Fe3O4颗粒，后者的吸附容量分别为9.45和9.72 mg/g。对接触时间、pH值、竞争阴离子、初始铬浓度和温度等各种吸附影响参数进行了优化。采用Freundlich和Langmuir等温线对吸附过程进行了解释。吸附动力学与准二级动力学和颗粒内扩散模型拟合良好。计算得到的热力学参数表明铬吸附过程是自发的且吸热的。
