Jahan Shanaz, Salman Muhammad, Alias Yatimah Binti, Abu Bakar Ahmad Farid Bin, Mansoor Farrukh, Kanwal Shamsa
Department of Geology, Faculty of Science, University of Malaya, Kuala Lumpur 50603, Malaysia.
Dalton Trans. 2020 Jun 23;49(24):8265-8273. doi: 10.1039/d0dt01274b.
Herein, we demonstrate a hydrothermal route to the one-pot synthesis of polymeric mesoporous silica microcubes (P@MSMCs) for the adsorption of heavy metal ions. During the synthesis of P@MSMCs from column silica gel, the roles and combination of the polymer and an etchant were characterized. Moreover, the porosity of P@MSMCs was tailored by adjusting the reaction temperature between 75 °C and 200 °C. The characterization through UV, FTIR, FESEM, XRD, BET, and EDX techniques exhibited that P@MSMCs have a well-ordered mesoporous structure with cubic morphology. The P@MSMCs had a diameter of 2 μm, with an average pore volume and pore size of 0.69 cm3 g-1 and 10.08 nm, respectively. The results indicated that the P@MSMCs have excellent adsorption capacity for Ag(i), Ti(iv), and Zn(ii) due to the formation of an aggregated complex. These aggregations led to affordable density difference-based separation of these metal ions through centrifugation, filtration or simple decantation. The removal efficiencies for Ag(i), Ti(iv), and Zn(ii) were observed to be 520, 720, and 850 mg g-1, respectively. The kinetic studies demonstrated that the adsorption performance fitted well to the pseudo-second-order kinetic model. The as-synthesized P@MSMCs were stable in the wide pH range of 4-8. Significantly, the recycling or reuse results displayed effective adsorption performance of these P@MSMCs for up to 5 cycles. The adsorption results obtained herein will promote the development of similar strategies for the removal of heavy metal ions from natural water.
在此，我们展示了一种水热法，用于一锅合成用于吸附重金属离子的聚合物介孔二氧化硅微立方体（P@MSMCs）。在由柱硅胶合成P@MSMCs的过程中，对聚合物和蚀刻剂的作用及组合进行了表征。此外，通过将反应温度调节在75℃至200℃之间来调整P@MSMCs的孔隙率。通过紫外、傅里叶变换红外光谱、场发射扫描电子显微镜、X射线衍射、比表面积分析仪和能谱分析技术表征显示，P@MSMCs具有立方形态的有序介孔结构。P@MSMCs的直径为2μm，平均孔体积和孔径分别为0.69 cm3 g-1和10.08 nm。结果表明，由于形成了聚集络合物，P@MSMCs对Ag(i)、Ti(iv)和Zn(ii)具有优异的吸附能力。这些聚集导致通过离心、过滤或简单倾析实现基于密度差异的这些金属离子的经济可行的分离。观察到Ag(i)、Ti(iv)和Zn(ii)的去除效率分别为520、720和850 mg g-1。动力学研究表明，吸附性能很好地符合准二级动力学模型。合成的P@MSMCs在4-8的宽pH范围内稳定。重要的是，回收或再利用结果显示这些P@MSMCs在多达5个循环中具有有效的吸附性能。本文获得的吸附结果将促进开发从天然水中去除重金属离子的类似策略。
