Department of Chemical Engineering, Vaal University of Technology, Private Mail Bag X021, Vanderbijlpark 1900, South Africa.
Department of Chemical Engineering, Vaal University of Technology, Private Mail Bag X021, Vanderbijlpark 1900, South Africa.
Int J Biol Macromol. 2019 Feb 15;123:664-676. doi: 10.1016/j.ijbiomac.2018.11.082. Epub 2018 Nov 14.
The multi-functional chitosan is important for the development of novel adsorbents which is needed for the effective removal of scavenging metal ions from water and wastewater. In this study the functionalized materials were characterize by FTIR, SEM/EDX, TGA/DTA, BET and XRD. Physicochemical parameters including pH, contact time, ionic strength and temperature were investigated in batch mode to optimize the conditions to be applied on a commercial scale for the maximum removal of metal ions using batch applications. The results showed that adsorption performance of grafted cross-linked chitosan beads can be modeled efficiently by Langmuir isotherm and pseudo-second order kinetic model. Thermodynamic parameters such as Gibb's free energy change (∆G°), enthalpy change (∆H°) and entropy change (∆S°) were calculated and the results showed the adsorption of Pb(II), Cu(II), Ni(II), Zn(II) and Cd(II) ions onto grafted crosslinked chitosan beads (G/ECH-CS) are spontaneous and endothermic in nature. Batch regeneration of the spent adsorbent from the single component mixture was effective. Multiple adsorption/desorption experiments were also carried out, and it was found that 0.0% mass loss of the G/ECH-CS was observed after the third cycle of adsorption/desorption studies.
多功能壳聚糖对于新型吸附剂的发展非常重要，这些吸附剂对于从水中和废水中有效去除清除金属离子是必需的。在这项研究中，通过傅里叶变换红外光谱（FTIR）、扫描电子显微镜/能谱仪（SEM/EDX）、热重分析/差示扫描量热法（TGA/DTA）、比表面积和孔隙度分析仪（BET）和 X 射线衍射仪（XRD）对功能化材料进行了表征。在批量模式下研究了包括 pH 值、接触时间、离子强度和温度在内的物理化学参数，以优化条件，以便在商业规模上应用于最大程度地去除金属离子。批量应用。结果表明，接枝交联壳聚糖珠的吸附性能可以通过 Langmuir 等温线和拟二级动力学模型有效地进行建模。计算了热力学参数，如吉布斯自由能变化（∆G°）、焓变（∆H°）和熵变（∆S°），结果表明 Pb(II)、Cu(II)、Ni(II)、Zn(II)和 Cd(II)离子吸附到接枝交联壳聚糖珠（G/ECH-CS）是自发和吸热的。从单一组分混合物中对用过的吸附剂进行批量再生是有效的。还进行了多次吸附/解吸实验，发现 G/ECH-CS 在第三次吸附/解吸研究循环后观察到 0.0%的质量损失。
