Comments on Characterization and adsorption capacity of raw pomegranate peel biosorbent for copper removal

This article aims to discuss (1) misapplications of the iodine number to determine the surface area of an adsorbent, (2) inconsistency discussions about FTIR, (3) incorrect assumptions regarding pKa of surface oxygen functionalities, (4) invalid discussions on adsorption mechanisms, (5) inaccurate calculations on the adsorption energy of the Dubinin Radushkevich equation, (6) incorrect expressions for the kinetic models (i.e., intra-particle diffusion and Elovich) and inconsistent data points in experimental data and model fitting, (7) mistakes in calculating the thermodynamic parameters, and (8) other miscellaneous errors. The author hopes that this work will contribute to avoiding the propagation of incorrect information in the scientific community in the field of adsorption studies. (C) 2016 Elsevier Ltd. All rights reserved.