In the present study, the characteristics of leachate generated from dumpsite called 'Zapote' located in southern region of Tamaulipas, Mexico were evaluated. The adsorption of non-biodegradable organic matter measured as chemical oxygen demand (COD), color and heavy metals from leachate on activated carbon (AC) prepared in acid media from Guadua amplexifolia bamboo has been studied. In addition, the computation of kinetic parameters during the adsorption process as well as the most probable mechanisms was determined. The ACs were analyzed by using scanning electron microscopy and Fourier transform infrared spectroscopy. The experimental data showed that the ACs removed up to 81.4% of color and reduced COD up to 91.6% after 9 h of reaction at 60°C. For heavy metals, the maximum adsorption uptake was achieved at pH = 8.0 within 20 min with removal percentages of 87.0% (Pb(II)), 43.0% (Cu(II)) and 30.5% (Ni(II)). A pseudo-second-order model explained the adsorption kinetics most effectively for Pb, Ni and Cu, while a pseudo-first order was found for Zn. The AC synthesized from the G. amplexifolia species could be potentially used as an effective adsorbent in the reduction of COD, and removal of color and heavy metals.
Keywords: Dumpsite; activated carbon; adsorption mechanism; stabilized leachate.