Temperature dependence of the volumetric properties of binary mixtures of (1-propanol, 2-propanol and 1,2-propanediol) at ambient pressure (81.5Â kPa)

Excess molar volumes VmE, have been investigated from density measurements using a vibrating u-tube densimeter for binary mixtures of (1-propanol + 2-propanol, 1-propanol + 1,2-propanediol and 2-propanol +1,2-propanediol) over the entire range of compositions in the temperature range of (293.15 to 343.15) K and ambient pressure (81.5 kPa). Thermal expansion coefficients α, excess thermal expansion coefficients αE, isothermal coefficients of pressure excess molar enthalpy (∂HmE / ∂P)T,x, partial excess molar volumes ViE, and partial excess molar volumes at infinite dilution ViE,0, were calculated from experimental densities. The excess molar volumes are negative over the whole mole fraction range for binary mixtures of (1-propanol +2-propanol) and (2-propanol + 1,2-propanediol) and become more negative with increasing temperature from (293.15 to 343.15) K. The excess molar volumes of (1-propanol + 1,2-propanediol) is negative and it is increases at 1-propanol rich region (x1 > 0.64) and decreases at opposite extreme with increasing temperatures. The excess molar volumes were correlated with a temperature dependent Redlich-Kister type equation.