Measurement of critical temperature and critical pressure of tert-butanol and alkane mixtures

Tert-butanol is a good additive for improving gasoline performance, but as two of the most important thermodynamic properties, the critical temperature (T-c) and critical pressure (p(c)) of tert-butanol and alkane systems have not been studied. In this work, the experimental data of the T-c and p(c) of five binary systems (tert-butanol + cyclohexane, tert-butanol + n-hexane, tert-butanol + n-heptane, tert-butanol + n-octane, and tert-butanol + nnonane) and a ternary system (tert-butanol + n-heptane + n-octane) were obtained using a flow method. The T-c and p(c) of the binary systems were fitted using the Redlich-Kister equations with maximum average absolute relative deviations (AARDs) of 0.19%and 0.36% for T-c and p(c), respectively. The T-c and p(c) for tert-butanol + n-heptane + n-octane were correlated by Singh and Sharma's equations and Cibulka's equations with AARDs less than 0.09% and 032%, respectively. The experimental data of T-c and p(c) were also used to verify and improve the accuracy of our previous prediction model. Published by Elsevier B.V.