Two solutions to adsorption equations for pore diffusion

Two solutions for the prediction of concentration vs time decay curves in agitated batch adsorbers, based on external mass transfer and pore diffusion, are presented and these enable mass transfer coefficients and pore diffusivities to be estimated by fitting to experimental data. Solutions have been developed for predicting concentration vs time decay curves for the adsorption of pollutants from water. The first solution, Model 1, applies a polynomial curve fit equation to the experimental concentration-time data and then differentiates the equation to yield d C/d t values at various time values. Certain problems were encountered in its application and therefore Model 2 was developed; this model uses an exponential curve fit equation and yielded results which were in better agreement with experimental data. Consequently a more rigorous program was developed to apply Model 2 to the experimental data. The solutions enable theoretical data to be compared with experimental results and 'best fit' external mass transfer coefficients and pore diffisivities to be determined for various systems.