School of Engineering, University of British Columbia, Kelowna, BC, V1V 1V7, Canada.
Institute for Nanoscience and Nanotechnology (INST), Sharif University of Technology, Tehran, Iran.
Chemosphere. 2021 Feb;264(Pt 2):128466. doi: 10.1016/j.chemosphere.2020.128466. Epub 2020 Oct 5.
Ethylenediamine-functionalized Zr-based metal-organic framework (MOF, UiO-66-EDA) was prepared via Michael addition reaction to investigate its potential for adsorption of heavy metal ions from water. Specifically, the influence of agitation time, solution pH, the dosage of the adsorbent, initial metal ion concentration, temperature, and coexistence of other metal ions was investigated on the removal efficiency of UiO-66-EDA towards Pb(II), Cd(II), and Cu(II) metal ions. The pseudo-second-order kinetic model governed the adsorption of these ions onto the UiO-66-EDA. Langmuir isotherm model matched the experimental isotherm of adsorption with a maximum adsorption capacity of 243.90, 217.39, and 208.33 mg/g for Pb, Cd, and Cu ions, respectively. The adsorption of Pb, Cd, and Cu ions onto UiO-66-EDA was dependent on electron exchange, electron sharing, electrostatic and covalent interactions between the metal ions as well as the abundant functional groups on UiO-66-EDA surface. Thermodynamic parameters such as free energy changes (ΔG), standard enthalpy changes (ΔH), and standard entropy changes (ΔS) were calculated, which revealed spontaneous and endothermic nature of the adsorption process. The UiO-66-EDA was stable and recyclable during adsorption studies of Pb, Cd, and Cu ions, suggesting its potentiality as an adsorbent for heavy metals recovery.
乙二胺功能化的 Zr 基金属有机骨架（MOF，UiO-66-EDA）通过迈克尔加成反应制备，以研究其从水中吸附重金属离子的潜力。具体而言，考察了搅拌时间、溶液 pH 值、吸附剂用量、初始金属离子浓度、温度以及共存的其他金属离子对 UiO-66-EDA 去除 Pb(II)、Cd(II)和 Cu(II)金属离子效率的影响。这些离子在 UiO-66-EDA 上的吸附受伪二级动力学模型控制。Langmuir 等温模型与吸附的实验等温线相匹配，对于 Pb、Cd 和 Cu 离子，UiO-66-EDA 的最大吸附容量分别为 243.90、217.39 和 208.33mg/g。Pb、Cd 和 Cu 离子在 UiO-66-EDA 上的吸附取决于电子交换、电子共享、静电和共价相互作用以及 UiO-66-EDA 表面上丰富的官能团。计算了自由能变化 (ΔG)、标准焓变 (ΔH) 和标准熵变 (ΔS) 等热力学参数，表明吸附过程是自发和吸热的。在 Pb、Cd 和 Cu 离子吸附研究中，UiO-66-EDA 是稳定且可回收的，表明其作为重金属回收吸附剂的潜力。
