Furfural removal from liquid effluents by adsorption onto commercial activated carbon in a batch heterogeneous reactor

Currently, the presence of furfural at low concentrations in different industrial effluents presents an environmental problem. In this work, the optimization of the main operating conditions of a batch heterogeneous reactor for furfural removal by adsorption onto commercial activated carbon were determined. In this sense, the effect of the commercial activated carbon concentration, operating temperature, and the agitation rate in the reactor were studied. In all experiments, the adsorption data have engaged in behavior that can be represented by pseudo-second order model. In liquid effluents with initial concentrations of furfural equal to 1 or 2 g dm(-3), the 90% furfural removal requires a minimum concentration of adsorbent in the reactor equal to 11 or 12 g dm(-3), respectively. The optimum agitation rate and temperature were around 100 rpm and 303-308 K, respectively. Equilibrium data at different temperatures were represented by Langmuir equation. The thermodynamic parameters of activation energy (E-a = 43.1 kJ mol(-1)) at different furfural concentrations, standard free energy (Delta G degrees = -16.1 kJ mol(-1)), standard enthalpy (Delta H degrees = -21.8 kJ mol(-1)), and standard entropy (Delta S degrees = -18.8 J mol(-1) K-1) of the adsorption process were determined. (C) 2014 Elsevier B.V. All rights reserved.