Biosorption of copper(II) ion from wastewater onto green waste tea: Isotherm and kinetic modeling studies

摘要

This paper studied the ability of using green tea waste (GTW) as an environment-friendly biosorbent for the removal of Cu(II) from aqueous solutions by batch operation. Various operating parameters such as equilibrium contact time, initial metal ion concentration, pH, and adsorbent dosage have been studied. The results indicated that the biosorption process was occurred within 120 min. equilibrium contact time for Cu(II) concentration range from 10 to 120 mg/l. It was found that, different concentration of copper solution reached equilibrium at different times. About 0.3 g of GTW was found to be enough to remove 91% of 10 mg/l initial copper ion concentration from 100 ml metal solution. The optimum biosorption capacity was at pH 6. The equilibrium adsorption data for Cu(II) were better fitted to the Freundlich adsorption isotherm model. The kinetic process of Cu(II) biosorption onto GTW was found to fit the pseudo-second-order model. Therefore, it is proven that the GTW can be used as efficient, economical means and environment-friendly to remove Cu(II) presence in the water/wastewater.