Removal of bisphenols A and S by adsorption on activated carbon clothes enhanced by the presence of bacteria.

This study investigated the adsorption of two endocrine-disrupting chemicals, bisphenol A (BPA) and S (BPS), from water using activated carbon clothes (ACCs), as-received and oxidized, in the absence and presence of bacteria, analyzing both kinetic and equilibrium adsorption data. Kinetic study of the different systems showed that the adsorption rate was affected both by the oxidation of the adsorbent and by the presence of bacteria. Bisphenol adsorption kinetics followed a second-order kinetic model, with rate constants between 0.0228 and 0.0013 g min mol. ACC was a much better adsorbent of E. coli compared to granular activated carbons, achieving 100% adsorption at 24 h. ACC oxidation reduced the adsorption capacity and the adsorbent-adsorbate relative affinity due to the decrease in carbon surface hydrophobicity. Conversely, the presence of bacteria in aqueous solution increased the ACC surface hydrophobicity and therefore enhanced the adsorption capacity of BPA and BPS on ACC, which was 33% and 24%, respectively. In all cases, more BPS than BPA was removed due to the greater dipolar moment of the former. Results found show that activated carbon clothes in the presence of bacteria can be an adequate process to remove bisphenol A and S from different aqueous systems.