抄録
A simple method for the estimation of an adsorption isotherm based on the analysis of an experimental desorption curve was studied. As an adsorption isotherm, the Toth equation was employed. Two simple methods taking into account the effect of a mass transfer rate were proposed. In the two methods, however, concentration dependence of an overall mass transfer coefficient on the amount adsorbed was neglected. The two methods and the equilibrium desorption method were applied to several liquid phase adsorption systems to determine adsorption isotherms. It was concluded that the two methods proposed here gave adsorption isotherms within about 2% error in most cases, and that the accuracy of the equilibrium desorption method was insufficient in a case where the value of the dimensionless longitudinal distance or bed length (Z) is small. The conditions under that the equilibrium desorption method can he used were clarified by analyzing theoretical desorption curves numerically calculated. The error of the equilibrium desorption method is governed by the combination of the dimensionless equilibrium and kinetic parameters r, Z and Toth equation parameter t. The error decreases as non-linearity of an adsorption isotherm is emphasized, and as the value of Z increases. By using the three methods properly according to the experimental conditions, an adsorption isotherm can be estimated within about 2% error. Only two preliminary data, namely one desorption curve and one pulse response curve, are required.
