Evaluation of Phenol and Bisphenol A (BPA) adsorption in commercial activated carbon from different carbonaceous matrices

The removal of toxic organic compounds and organic micro-pollutants from industrial wastewater is a current and growing concern to improve water quality for reuse. To improve water quality, some treatments have been shown to be effective, such as the activated carbon adsorption treatment. This study evaluated the adsorption of phenol and bisphenol A (BPA) onto activated carbon from two different carbonaceous matrices: bituminous (CB) and vegetable (CV). The activated carbons were characterized by scanning electron microscopy (SEM) equipped with an energy dispersive spectrometer (EDS), Fourier-transformed infrared spectroscopy (FTIR) and BET (Brunauer et al., 1938) surface area. Assays were performed to determine equilibrium time and adsorption isotherms (Freundlich and Langmuir). Adsorption onto the two types of carbons favored phenol removal, resulting in 96% for the CB carbon and 91% of phenol removal for CV carbon. However, the adsorption of bisphenol A was efficient only for the CB carbon, resulting in 90% and 20% of BPA removal for CB and CV, respectively. The adsorptive capacities determined for CB carbon were 125 mg phenol.g^-1 and 76 mg BPA.g^-1, and for CV carbon were 99 mg phenol.g^-1 and 27 mg BPA.g^-1. The results are related to the presence of acid groups in CV carbon and to the hydrophobicity of BPA, which makes the adsorption process unfavorable.

adsorption isotherms; industrial wastewaters; micro pollutants