Zeolitic imidazole framework (ZIF) – zinc oxide nanocomposite: synthesis and ultrasound-assisted pollutant removal from the binary system

Nowadays, the overuse of dyes and their presence in wastewater can be considered as an environmental concern.In this study, zeolitic imidazole framework-8 (ZIF-8), zinc oxide (ZnO), and their composite (ZnO-ZIF-8) were synthesized and characterized by scanning electron microscopy, Fourier transform infrared, X-ray diffraction, and zeta potential techniques.The synthesized materials were used for the removal of Malachite green (MG) from aqueous media via a batch adsorption process.The adsorption isotherm, and the effects of operational parameters, including adsorbent dosage, initial dye concentration, time, and pH on dye removal, were comprehensively studied.The adsorption capacity of the composite was 3,654 mg/g.The results showed that the experimental data were fitted by the Freundlich isotherm model with a high correlation coefficient (0.9676).Moreover, the ability of the prepared adsorbents (ZIF-8, ZnO, and ZnO-ZIF-8) for the removal of dyes from binary systems containing MG and Rhodamine-B (Rh-B) was evaluated.