RESEARCH ARTICLE


Evaluation of Equilibrium Sorption Isotherm Equations



Chiachung Chen*
Department of Bio-Industrial Mechantronics Engineering, National ChungHsing University, Taichung, 40227, Taiwan


© 2013 Chen

open-access license: This is an open access article distributed under the terms of the Creative Commons Attribution 4.0 International Public License (CC-BY 4.0), a copy of which is available at: https://creativecommons.org/licenses/by/4.0/legalcode. This license permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

* Address correspondence to this author at the Department of Bio-Industrial Mechantronics Engineering, National ChungHsing University, Taichung, 40227, Taiwan; Tel: +886422857562; Fax: +886422857135; E-mail: ccchen@dragon.nchu.edu.tw


Abstract

The sorption isotherm is important information for evaluating the ability of an adsorption system to treat the industrial waste water. In this study, eleven datasets from literatures were selected and three two-parameter and three-parameter equations were used to evaluate adsorption systems. Quantitative criteria included six error functions, and the quantitative criterion was residual plots. Isotherm constants differed by linearization and nonlinear regression analysis, especially for the three-parameter equations. The results indicated the inconsistent results of the error functions for select-ing the adequate equations. Residual plots were useful to observe the fitting ability of isotherm equations. Temperature has a significant effect on isotherm constants.

Keywords: Isotherm equation, Error functions, Residual plots.