Ion-Exchange Calculations Using Spreadsheets

Abstract

A simple set of calculations using a Microsoft Excel spreadsheet can help students determine ion-exchange equilibrium parameters, essential for the design of industrial equipment. Equilibrium parameters are evaluated from experimental isotherms obtained from different zeolites using the action-law model by means of nonlinear curve fitting (Marquardt method). Students will be able to discriminate between ideal and nonideal systems by observation of activity coefficients. The possibility of using the spreadsheet with different types of ion-exchange materials is also validated by comparing the model results with experimental data from papers available in the recent literature. Although the laboratory experience is laborious, it is very satisfactory.