Abstract A new adsorbent was successfully fabricated by chemically linking pyromellitic acid onto a zirconium-based metal-organic framework composite for selective adsorption of Pd(II) from an aqueous solution. The adsorbent was characterized by Fourier transform infrared spectroscopy, Brunauer–Emmett–Teller equation and scanning electron microscope. The adsorption capacity, selectivity and repeatability of the adsorbent were tested by batch experiments. The optimum pH was 2.0, and the maximum adsorption capacity at room temperature was 226.1 mg/g. In the kinetic experiments, the adsorption process achieved equilibrium within 5 hours and generally conformed to the quasi-second kinetics and Freundlich isotherm model. The N-H and O-H groups on the adsorbent interacted with Pd(II) by electrostatic and coordination action. The adsorbent maintained excellent adsorption capacity after at least 5 cycles. At the same time, the selectivity of the adsorbent in aqueous solution is excellent from interfering ions. Therefore, the new adsorbent will have an obvious application prospect on the recovery of palladium.

中文翻译：

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水溶液中Pd(II)离子在均苯四酸改性-UiO-66-NH2上的吸附行为

摘要 通过将均苯四酸化学连接到锆基金属-有机骨架复合材料上，成功制备了一种新型吸附剂，用于选择性吸附水溶液中的 Pd(II)。通过傅里叶变换红外光谱、Brunauer-Emmett-Teller 方程和扫描电子显微镜对吸附剂进行表征。通过批量实验对吸附剂的吸附容量、选择性和重复性进行了测试。最适pH为2.0，室温下最大吸附量为226.1 mg/g。在动力学实验中，吸附过程在5小时内达到平衡，基本符合准秒动力学和Freundlich等温线模型。吸附剂上的 NH 和 OH 基团通过静电和配位作用与 Pd(II) 相互作用。吸附剂在至少 5 次循环后仍保持优异的吸附能力。同时，吸附剂在水溶液中的选择性极好，不受干扰离子的影响。因此，新型吸附剂在钯的回收方面具有明显的应用前景。