Phenols removal from industrial effluents through novel polymeric resins: Kinetics and equilibrium studies

The efficient removal of phenols from wastewaters has increasingly become a significant environmental concern due to its high toxicity even at low concentrations. In this research work, phenols removal from aqueous solution was evaluated by using Amberlyst A26, a strong-base anion exchange resin, and Amberlite IRA-67, a weak-base anion exchange resin. The influence of phenols concentration in the feed stream was investigated as well as the effect of recirculation time. Equilibrium data fitted to the Langmuir, Freundlich and Temkin isotherms revealed Langmuir isotherm provided the best correlation for both resins (R-2=0.99). Kinetic studies performed based on pseudo-first order, pseudo-second order and intraparticle diffusion models showed that although the correlation coefficients of the second order model were the highest (R-2 = 1) and also the SSE values were the lowest (<2%), the kinetics of phenols uptake could be also satisfactorily described by intraparticle diffusion. On the other hand, results revealed that phenols uptake is a spontaneous process for Amberlyst A26 (Delta G degrees = -1.55 kJ mol(-1)), whereas it is not spontaneous for Amberlite IRA-67 (Delta G degrees = 3.06 kJ mol(-1)). Finally, Amberlyst A26 was confirmed to be considerably more efficient than Amberlite IRA-67 for the potential removal of phenols from industrial effluents. (C) 2016 Elsevier B.V. All rights reserved.