Adsorption of Nickel Ions From Aqueous Solutions by Green Tea Waste

Abstract

In this research, the green tea waste (GTW) was utilized for the removal of Ni(II) ion from aqueous solutions. Adsorption experiments were conducted under various conditions where the batch method was used to determine the best adsorption ratio and the adsorption capacity for the concentration used of Ni(II) ion between 10-100 mg/L, the results show that the best concentration was 10 mg/L where the adsorption ratio was 92% and the adsorption capacity was 2.3 mg/g. The adsorbent dose was 4 g/L, and the shaking time found that it equal to 60 min and the best pH value between (3-8). The effect of temperature and thermodynamic functions wear also studied, the adsorption capacity was increased with increased the temperature and the reaction was endothermic. The equilibrium isotherm data was analyzed using the Langmuir, Freundlich and Tempkin equations. The rate constant k2 for the adsorption of Ni(II) ion is equal to 0.0571 g/mg.min.