Evaluation of the Biosorption Capacity and the Methanogenic Inhibition in the Removal of Copper by an Anaerobic Sludge

Proceedings (senza ISBN) del Convegno Gricu "Ingegneria Chimica: Le Nuove Frontiere”, Le Castella (KR), 14-17 settembre 2008. - Biosorption of Cu(II) on anaerobic sludge was investigated in a batch reactor. The study demonstrated the effectiveness of biosorption process: the percentage of copper adsorbed onto sludge particles was 99.5%. Equilibrium data were fitted using Langmuir and Freundlich isotherm models and the results compared by non-linear regression. A better agreement with equilibrium data was shown by Freundlich isotherm. Effects on methane production were also studied in order to investigate if the biosorption process can take place without any change in the biogas production capacity of anaerobic sludge. Results demonstrated that methane production rapidly drops for low metal concentration, and it can be partially recovered with further metals additions.