Department of Health and Environment Engineering, Catholic Kwandong University, Gangneung 25601, South Korea.
Department of Environmental Engineering, Catholic Kwandong University, Gangneung 210-701, South Korea.
Int J Biol Macromol. 2018 Jul 15;114:1315-1324. doi: 10.1016/j.ijbiomac.2018.04.008. Epub 2018 Apr 7.
The present study deals with the preparation and characterization of mesoporous synthetic hectorite (MSH) clay which further encapsulated with Na-alginate for the preparation of mesoporous synthetic hectorite-alginate beads (MSH-AB) where Ca act as a cross-linking agent. The detail characterization of MSH and MSH-AB were carried out by various physicochemical techniques. The thermogravimetric analysis study showed better thermal stability results for MSH-AB. The textural properties results of MSH and MSH-AB showed the high surface area 468, 205m/g, and the pore volume of 0.34, 0.29cm/g respectively. The applicability of powder MSH and MSH-AB in wet (W) and dry (D) forms were assessed for the removal of cationic dye, methylene blue (MB) by optimizing various batch adsorption parameters. The Langmuir monolayer adsorption capacity obtained for MSH-AB-W showed significant high adsorption efficacy (i.e., 785.45mgMB/g) compared to the MSH-AB-D (357.14mgMB/g) and powder MSH materials (196.00mgMB/g). The adsorption isotherm studies showed that the Langmuir isotherm model was best suitable for MSH, whereas the Freundlich model was utilised to describe the adsorption behavior of organized hydrogel composite beads. The pseudo-second-order kinetics model was observed best for MB sorption onto MSH, whereas pseudo-first order useful to describe the kinetic behavior of MSH-AB. The regeneration experimental results revealed that MSH-AB-W could be recycled more than six cycles with high MB removal efficiency. Furthermore, the adsorption property of the MSH-AB-W was examined for the binary mixture of MB with other dye solutions such as Methyl Red (MR), Methyl Orange (MO), Alizarine Yellow (AY), and Remazol Brilliant Blue (RBB) to evaluate the selective adsorption efficiency. The MSH composite beads were found potentially suitable as an efficient, selective and recyclable adsorbent for the removal of MB from the aqueous solutions.
本研究制备并表征了中孔合成羟硅镁石（MSH）粘土，然后用 Na-海藻酸钠进一步封装，制备中孔合成羟硅镁石-海藻酸钠珠（MSH-AB），其中 Ca 用作交联剂。通过各种物理化学技术对 MSH 和 MSH-AB 进行了详细的表征。热重分析研究表明，MSH-AB 的热稳定性更好。MSH 和 MSH-AB 的结构性能结果分别显示出高表面积 468、205m/g 和孔体积 0.34、0.29cm/g。评估了粉末 MSH 和 MSH-AB 在湿（W）和干（D）形式下对阳离子染料亚甲基蓝（MB）的去除应用，优化了各种批处理吸附参数。与 MSH-AB-D（357.14mgMB/g）和粉末 MSH 材料（196.00mgMB/g）相比，MSH-AB-W 的单层吸附容量（即 785.45mgMB/g）表明吸附效率显著提高。吸附等温线研究表明，Langmuir 等温线模型最适合 MSH，而 Freundlich 模型用于描述有机水凝胶复合珠的吸附行为。观察到伪二阶动力学模型最适合 MB 吸附到 MSH 上，而准一阶模型可用于描述 MSH-AB 的动力学行为。再生实验结果表明，MSH-AB-W 可以在高 MB 去除效率的情况下回收超过六次。此外，还研究了 MSH-AB-W 对亚甲基蓝与其他染料溶液（如甲基红（MR）、甲基橙（MO）、茜素黄（AY）和丽春红亮蓝（RBB））的二元混合物的吸附性能，以评估其选择性吸附效率。MSH 复合珠被发现是一种潜在的高效、选择性和可回收的吸附剂，可从水溶液中去除 MB。
