Removal of cobalt(II) from aqueous solution by spent green tealeaves

The removal of Co2+ in aqueous solution by spent green tealeaves (SGTL) was studied in batch conditions. The bio-sorbent was characterized by the infrared spectroscopy, Boehm’s titration and by pHpzc. The optimum pH value was found in the range of 4 to 6. The sorption was fast, obeyed the pseudo second order model, and favored at low temperature. The bio-sorption capacity recorded a rate of 83.52% using 0.25 g of SGTL. The isotherm followed the Langmuir model. The Co2+ bio-sorption is exothermic, reversible and favorable and that it was carried out by physic sorption with low activation energy.