Exhausted Yerba Mate Leaves (Ilex paraguariensis) as Biosorbent for the Removal of Metals from Aqueous Solutions

Yerba mate is the most popular tea-like beverage of South America. Consequently, there is a huge generation of residues of exhausted yerba mate and these may be used for removal of metals. The capability of exhausted yerba mate leaves in the removal of metals was evaluated in this study. The greatest adsorption was found to be at pHs below 5 and the adsorption capacity was 12.28, 11.77 and 8.80 mg g(-1) for Pb(II), Cr(III) and Cr(VI), respectively.