Calculation of Distillation Curves of Hydrocarbon and Oxygenate Mixtures Using Activity Coefficients

This work is devoted to the calculation of the distillation curve of mixed fuels including petroleum hydrocarbons and biocomponents. When calculating the distillation curves of such fuels using the standard technique, in some cases there is a significant deviation at the beginning of the graph. Therefore, in this work, activity coefficients were used to determine the saturated vapor pressure of the mixture when calculating the distillation curves. The distillation curves of the tetradecane – propanol-1 mixture were calculated taking into account the activity coefficient in the Raoult equation when determining the saturated vapor pressure of the mixture. The obtained distillation curves were compared with the experimental data also obtained by the authors of the work. Systems with different contents of the oxygen-containing component (25, 50, and 75 vol %) were considered. The UNIFAC model was used to calculate the activity coefficient. The results showed that the use of activity coefficients leads to a decrease in the discrepancy between the calculated and experimental distillation curves for mixtures with a biocomponent content of up to 50%.