Comments on the calculation of thermodynamic adsorption equilibrium constant using the distribution coefficient in Journal of Molecular Liquids 380 (2023) 121725

Abstract

This comment discussed the calculation of the standard equilibrium constant thermodynamic parameters about the paper published in Journal of Molecular Liquids 380 (2023) 121725. Recently, Khankhasaeva et al. (2023) published a high academic paper to reveal the adsorption kinetic and thermodynamic regularities of diclofenac (DCF) on Fe2O3-pillared montmorillonites (Fe-PMts). Although the author tries to convert the distribution coefficient (Kd) to the standard equilibrium constant (Ko), the calculation formula is incorrect due to the confusion of adsorbate and adsorbent. This creates dimension for Ko obtained from Eq. (2). In this comment, the origin and background of this kind of error is analyzed and the method for correcting the error is presented. We hope this comment clarifies the essence of calculating the standard equilibrium constant by using the distribution coefficient, so others avoid the propagation of this kind of error.