Zinc adsorption from aqueous solution using lemon, orange, watermelon, melon, pineapple, and banana rinds

In this study, six fruit rinds, chemical activated using ZnCl2 and carbonized by microwave, were used as biosorbent to remove zinc from aqueous solution. Fruit kind, microwave treatment time and adsorption contact time effects on zinc biosorption yield were examined. The characterization of raw materials and synthesized biosorbents were realized by Fourier-transform infrared spectroscopy (FT-IR). The dried fruits rinds were activated for 2 or 4 h using ZnCl2 and carbonized for 1, 2, 3 or 4 min at 800 W microwave power. Zinc biosorption yield was determined using ultraviolet-visible spectroscopy (UV-Vis). Maximum zinc biosorption capability was determined as 39.18 mg/g for lemon, 35.78 mg/g for orange, 14.76 mg/g for watermelon, 13.06 mg/g for melon, 12.2 mg/g for pineapple and 9 mg/g for banana rinds. The results indicate that the six fruits rinds can be used for zinc adsorption from aqueous solution as cost-effective and environmentally friendly biosorbent with high adsorption efficiency.