In selecting the optimum solvents of extractive distillation

multiple factors should be considered and the evaluation of these factors are often of fuzzy characteristics.In this paper a comprehensive fuzzy evaluation (CFE) model was used for choosing the solvents.At first the membership functions of factors influencing the solvent performance versus the judgment grades were determined and the fuzzy evaluation matrix

R

was given.Then the weight-distributed sets

A

were determined by multi-experts-scoring.At last

the comprehensive evaluation results were obtained based on all factors considered

and the candidate solvents were queued in the order of superiority.The CFE method was used to select the solvents of two extractive distillation processes for separating benzene/n-heptane and ethyl acetate/ethanol mixtures respectively

and the method proved to be successful with perspective industrial applications.