Synergistic, Hydrothermally Integrated Magnetic Graphene Oxide for Selective Ni(II) Removal From Aqueous Solutions

Heavy metals in water can pose a serious threat to biotic health and the environment. Herein, we describe the synthesis and characterization of magnetic graphene oxide (MGO) composites, followed by its application for nickel removal from aqueous solutions, which could help in the mitigation of its negative environmental impacts. The graphene oxide (GO) was prepared through Hummer's method followed by its magnetization to obtain MGO. Its synthesis was confirmed using various techniques such as FTIR, SEM, and EDX. The maximum of 94 ± 4% nickel removal was achieved at the optimized values of pH, contact time, and adsorbent doses that were found to be 7.00, 30 min, and 50 mg with 2 mL adsorbate volume, respectively. The MGO adsorption data were found well suited to the Langmuir isotherm, that revealed the maximum adsorption capacity of 83.69 mg/g for Ni(II) ions. The recyclability experiment resulted in a decrease of 13 ± 3% Ni(II) removal after three consecutive sorption–desorption procedures, reflecting the sustainability and better applicability of the prepared MGO. Our findings demonstrated excellent performance of MGO as compared to GO, proving to be an effective adsorbent and can be utilized to reduce Ni(II) related toxicities from aqueous systems.