Moradi Ehsan, Salehi Mohammad Mehdi, Maleki Ali
Catalysts and Organic Synthesis Research Laboratory, Department of Chemistry, Iran University of Science and Technology, Tehran, 16846-13114, Iran.
Heliyon. 2024 Jul 23;10(15):e35044. doi: 10.1016/j.heliyon.2024.e35044. eCollection 2024 Aug 15.
A bimetallic cobalt/nickel-based metal-organic framework (MOF), [Co/Ni(μ3-tp)(μ2-pyz)], denoted as Co/Ni-MOF, has been successfully prepared by a hydrothermal method. The MOF was prepared by incorporating mixed O and N donor ligands, specifically terephthalic acid (tp) and pyrazine (pyz). The Mesoporous Co/Ni-MOF was comprehensively characterized using various analytical methods such as XRD, BET, FT-IR, TGA (23 % char yields), SEM, and EDS analyses. The synthesized mesoporous Co/Ni-MOF was then used to absorb Co (II) from aquatic areas efficiently. Several critical parameters, such as the beginning Co (II) concentration (25-150 mg/L), the effect of pH (2-10), the duration of time (5-30 min), and the amount of adsorbent (0.003-0.02 g), were systematically investigated. Remarkably, the Mesoporous Co/Ni MOF displayed a significant adsorption capacity of 372.66 mg g in the optimum conditions, including pH = 6, amount of adsorbent = 0.003 g, duration of time = 25 min, and beginning Co (II) concentration = 150 mg/L. Adsorption data from the experimental studies of the mesoporous Co/Ni MOF are matched based on the non-linear pseudo-first-order (PSO) kinetic model (R = 0.9999), and a chemical process is suggested for chemisorption. Furthermore, the adsorption isotherms of Co (II) heavy metal ions (HMIs) are an excellent fit with the non-linear Temkin, indicating that they explain the sorbent/sorbate interactions concerning the heat of adsorption. It is evident from the thermodynamic parameters that adsorption is a spontaneous and favorable exothermic process. These results highlight the promising adsorption performance and potential applications of the mesoporous Co/Ni-MOF as an effective adsorbent for Co (II) elimination from aquatic areas. Four-cycle regeneration studies were the most effective for the Co (II) under study.
一种双金属钴/镍基金属有机框架材料（MOF），[Co/Ni(μ3 - tp)(μ2 - pyz)]，记为Co/Ni - MOF，已通过水热法成功制备。该MOF是通过引入混合的O和N供体配体，即对苯二甲酸（tp）和吡嗪（pyz）制备而成。采用多种分析方法，如XRD、BET、FT - IR、TGA（23%的炭产率）、SEM和EDS分析，对介孔Co/Ni - MOF进行了全面表征。然后将合成的介孔Co/Ni - MOF用于高效吸附水域中的Co（II）。系统研究了几个关键参数，如初始Co（II）浓度（25 - 150 mg/L）、pH值（2 - 10）的影响、时间持续（5 - 30分钟）以及吸附剂用量（0.003 - 0.02 g）。值得注意的是，在最佳条件下，即pH = 6、吸附剂用量 = 0.003 g、时间持续 = 25分钟以及初始Co（II）浓度 = 150 mg/L时，介孔Co/Ni MOF表现出372.66 mg/g的显著吸附容量。介孔Co/Ni MOF实验研究的吸附数据基于非线性伪一级（PSO）动力学模型进行拟合（R = 0.9999），并提出化学过程用于化学吸附。此外，Co（II）重金属离子（HMI）的吸附等温线与非线性Temkin模型拟合良好，表明它们解释了关于吸附热的吸附剂/吸附质相互作用。从热力学参数可以明显看出，吸附是一个自发且有利的放热过程。这些结果突出了介孔Co/Ni - MOF作为从水域中有效去除Co（II）的吸附剂的良好吸附性能和潜在应用。四循环再生研究对所研究的Co（II）最为有效。
