Metal–organic frameworks (MOFs) have received special attention from scientists owing to their excellent adsorption performance. However, the difficulty in separating MOFs from adsorbed metals following use has limited their application. A zeolitic imidazole-based MOF with broad applicability for sorption of Pb­(II) is examined. In this work, a novel adsorbent employing ZIF-8/calcium alginate microparticles was prepared using sodium alginate and ZIF-8. This adsorbent was characterized using scanning electron microscopy, Fourier-transform infrared spectroscopy, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The performance of the ZIF-8@CA microparticles in adsorbing Pb­(II) from a Pb­(II) solution was investigated, and the impacts of the initial Pb­(II) concentration, reaction time, pH, and reaction temperature on the reaction process were investigated. The results showed that ZIF-8@CA microparticles exhibited a maximum adsorption capacity of 1321.21 mg/g at pH 5 after 120 min, and the adsorption process was found to fit the Langmuir isotherm model (R 2 = 0.9856) and the pseudo-second-order kinetic model (R 2 = 0.9999). These results showed that the adsorption of Pb­(II) was an endothermic process. The regeneration experiment with ZIF-8@CA revealed that the removal efficiency of Pb­(II) was greater than 80% even after five cycles.

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