Determination of critical properties for binary and ternary mixtures of short chain alcohols and alkanes using a flow apparatus

•Critical properties of four binary systems and two ternary systems were measured.•All binary systems show non-ideal behavior especially for mixtures with ethanol.•All data of binary systems were fitted well with Redlich–Kister equation.•Critical surfaces of ternary systems were plotted using the Cibulka's expressions.

The critical temperatures and pressures of four binary systems and two ternary systems containing gasoline additives (ethanol + cyclohexane, ethanol + octane, 2-propanol + octane, 2-propanol + decane, ethanol + cyclohexane + octane and 2-propanol + octane + decane) were measured with a low-residence time flow apparatus. The critical properties were determined by observing critical opalescence and phase changes in a quartz glass tube. The expanded uncertainties of critical temperature and pressure were estimated to be less than ±0.4 K and ±0.01 MPa, respectively. The four binary systems show non-ideal behavior especially for ethanol + cyclohexane and ethanol + octane systems. The experimental data of all binary mixtures could be correlated to within 0.06% with the Redlich–Kister equations. Ternary mixtures are newly reported in this work and were correlated with Cibulka's and Singh's expressions.

Graphical abstractExperimental critical temperatures for the ethanol (1) + cyclohexane (2) + octane (3) system.Figure optionsDownload full-size imageDownload as PowerPoint slide