Comments on "Adsorption of 2-mercaptobenzothiazole from aqueous solution by organo-bentonite" by P. Jing, M.H. Hou, P. Zhao, X.Y. Tang, H.F. Wan

Mistakes and inconsistencies regarding adsorption of contaminants from aqueous solutions: A critical review

In recent years, adsorption science and technology for water and wastewater treatment has attracted substantial attention from the scientific community. However, the number of publications containing inconsistent concepts is increasing. Many publications either reiterate previously discussed mistakes or create new mistakes. The inconsistencies are reflected by the increasing publication of certain types of article in this field, including "short communications", "discussions", "critical reviews", "comments", "letters to the editor", and "correspondence (comment/rebuttal)". This article aims to discuss (1) the inaccurate use of technical terms, (2) the problem associated with quantities for measuring adsorption performance, (3) the important roles of the adsorbate and adsorbent pK_a, (4) mistakes related to the study of adsorption kinetics, isotherms, and thermodynamics, (5) several problems related to adsorption mechanisms, (6) inconsistent data points in experimental data and model fitting, (7) mistakes in measuring the specific surface area of an adsorbent, and (8) other mistakes found in the literature. Furthermore, correct expressions and original citations of the relevant models (i.e., adsorption kinetics and isotherms) are provided. The authors hope that this work will be helpful for readers, researchers, reviewers, and editors who are interested in the field of adsorption studies.

Comments on the paper "Removal of aqueous Hg(II) and Cr(VI) using phytic acid doped polyaniline/cellulose acetate composite membrane"

A mistake of using and applying pseudo-first order kinetic expression for adsorption systems has been pointed out. This discussion offered information for citing original idea of pseudo-first order kinetic expression. The original idea of initial adsorption rate calculated from pseudo-second order kinetic model was also presented. It suggested an important idea that author must not only be creative but also be careful while writing in order to publish more valuable and worth of reading papers.