In the multicomponent distillation, the prediction of composition profiles using the binary data is highly desirable because it is physically impossible to perform the experimental study of all systems in the industrial application. So in this study, following three methods using the binary data are proposed to predict the concentration profiles for the n-hexane/n-heptane/n-octane system and the methanol/2-propanol/water system :
1) assumption of constant number of overall vapor phase transfer units, [NOV]
2) solution of Maxwell-Stefan equation based on linearized theory
3) the general solution of Maxwell-Stefan equation
And, the experiment are performed in a 1 in. diameter Oldershaw column with 10 plates and 15 plates, in order to compare the predicted concentration profiles with the measured concentration profiles. The predicted concentration profiles using the assumption of constant [NOV] are severely deviated from the measured concentration profiles for both systems. But the predicted concent- ration profiles using other two methods are in good agreement with the measured concentration profiles. And three methods predict numbers of stages for a specified separation. In MeOH/IPA/Water system the predicted numbers of stages are different from each other. But in n-hexane/n-heptane/n-octane system three methods predict almost same numbers of stages with each other.