Henan Province Industrial Technology Research Institute of Resources and Materials, Zhengzhou University, Zhengzhou, Henan, 450001, PR China.
Henan Province Industrial Technology Research Institute of Resources and Materials, Zhengzhou University, Zhengzhou, Henan, 450001, PR China; School of Chemical Engineering, Zhengzhou University, Zhengzhou, Henan, 450001, PR China; National and Local Joint Engineering Research Center for Green Mineral Metallurgy and Processing, Zhengzhou, Henan, 450001, PR China; Provincial and Ministerial Joint Innovation Center for Resource Materials, Zhengzhou, Henan, 450001, PR China.
Chemosphere. 2021 Oct;280:130727. doi: 10.1016/j.chemosphere.2021.130727. Epub 2021 Apr 30.
In the work, sulfhydryl functionalized montmorillonite nanosheets based hydrogel balls were firstly synthesized for Pb(II) adsorption, and then characterized by scanning electron microscope (SEM), fourier transform infrared spectroscopy (FTIR), surface area analyzer (BET), thermogravimetry (TG), and zeta potential. Effects of initial solution pH, adsorbent dosage, contact time, temperature on Pb(II) adsorption of the resulting hydrogel balls were investigated systematically. The experimental results showed that the increase amount of sulfhydryl functionalized montmorillonite nanosheets (MMTNs-SH) maintained the hydrogel balls a better porous structure and bigger specific surface area, endowing it a bigger adsorption capacity. The adsorption process was fitted well with pseudo-second-order kinetics model and Freundlich model, and more than 97% of Pb(II) could be removed under the optimum conditions. Moreover, hydrogel spheres have a certain cycle performance. In addition, the interactions between Pb(Ⅱ) ions and the oxygen atoms in the hydroxyl groups and the sulfur atoms in the sulfhydryl groups, and the ion exchange in MMTNs-SH dominated the adsorption.
在这项工作中，首次合成了巯基功能化蒙脱土纳米片基水凝胶球用于 Pb(II)吸附，并通过扫描电子显微镜 (SEM)、傅里叶变换红外光谱 (FTIR)、比表面积分析仪 (BET)、热重分析 (TG) 和动电位仪进行了表征。系统研究了初始溶液 pH 值、吸附剂用量、接触时间、温度对所得水凝胶球吸附 Pb(II)的影响。实验结果表明，增加巯基功能化蒙脱土纳米片（MMTNs-SH）的量保持了水凝胶球更好的多孔结构和更大的比表面积，赋予其更大的吸附容量。吸附过程符合准二级动力学模型和 Freundlich 模型，在最佳条件下，超过 97%的 Pb(II)可以被去除。此外，水凝胶球具有一定的循环性能。此外，Pb(Ⅱ)离子与羟基中的氧原子和巯基中的硫原子之间的相互作用以及 MMTNs-SH 中的离子交换主导了吸附。
