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Heavy metal copper (Cu2+) ions contamination through the discharge of industrial effluent has caused serious environmental issues globally. As a result, the removal of Cu2+ ions from water bodies are of prime importance for human health and environmental protection. In the present study, the adsorption behaviour of zirconium (Zr)-based metal organic framework (MOF-801) prepared by solvothermal method in the removal of copper ion (Cu2+) from aqueous solution was studied. The results obtained from the batch mode adsorption studies revealed that at an initial Cu2+ concentration of 10 ​mg/L, contact time of 180 ​min and adsorbent dosage of 10 ​mg, the removal efficiency and equilibrium adsorption capacity of Cu2+ from the process were 97.80% and 9.78 ​mg/g, respectively. The influence of MOF-801 on the adsorption of Cu2+ ions was studied by Langmuir and Freundlich adsorption isotherm models. The graph was found to fit well with the Freundlich isotherm, and the MOF-801's maximal multilayer adsorption capacity was determined to be 16.58 ​mg/g. A kinetic study showed that Cu2+ removal was carried out in 180 ​min with a behaviour of pseudo-second-order kinetic model and in general, the majority of metal adsorption occurred within the first 30 ​min. After four cycles of adsorption-regeneration, a reusability test using adsorbent revealed a decline in adsorption removal effectiveness of less than 11%. The MOF-801 was shown to be effective in the removal of Cu2+ from wastewater treatment. [Display omitted] • Zr-based MOFs was successfully synthesized by one-pot solvothermal method for removing copper ions. • Pseudo-second-order kinetic model suitably described the kinetics of Cu adsorption. • The equilibrium data were fitted well with the Freundlich isotherm model. • Adsorption mechanism of Cu2+ ions on the Zr-based MOFs were investigated. • Adsorption efficiency by the Zr-based MOFs reached 89% after four cycles. [ABSTRACT FROM AUTHOR]

Abstract: Amine-functionalized adsorbents have attracted increasing interest in recent years for heavy metal removal. In this study, diethylenetriamine (DETA) was successfully grafted (through a relatively simple solution reaction) onto poly(glycidyl methacrylate) (PGMA) microgranules to obtain an adsorbent (PGMA-DETA) with a very high content of amine groups and the PGMA-DETA adsorbent was examined for copper ion removal in a series of batch adsorption experiments. It was found that the PGMA-DETA adsorbent achieved excellent adsorption performance in copper ion removal and the adsorption was most effective at pH>3 in the pH range of 1–5 examined. X-ray photoelectron spectroscopy (XPS) revealed that there were different types of amine sites on the surfaces of the PGMA-DETA adsorbent but copper ion adsorption was mainly through forming surface complexes with the neutral amine groups on the adsorbent, resulting in better adsorption performance at a higher solution pH value. The adsorption isotherm data best obeyed the Langmuir–Freundlich model and the adsorption capacity reached 1.5 mmol/g in the case of pH 5 studied. The adsorption process was fast (with adsorption equilibrium time less than 1–4 h) and closely followed the pseudo-second-order kinetic model. Desorption of copper ions from the PGMA-DETA adsorbent was most effectively achieved in a 0.1 M dilute nitric acid solution, with 80% of the desorption being completed within the first 1 min. Consecutive adsorption–desorption experiments showed that the PGMA-DETA adsorbent can be reused almost without any loss in the adsorption capacity. [Copyright &y& Elsevier]