Apparent molar heat capacities of aqueous solutions of 1-propanol, butane-1,4-diol, and hexane-1,6-diol at temperatures from 300 K to 525 K and a pressure of 28 MPa

Abstract

The heat capacities of dilute aqueous solutions of 1-propanol, butane-1,4-diol, and hexane-1,6-diol have been measured at 300 K < T< 525 K at p= 28 MPa. Extrapolation to infinite dilution gave values for C p,2 ∞. Literature values of (∂ 2 V 2 ∞/∂ T 2and C p,2 ∞at p= 0.1 MPa were used to calculate C p,2 ∞at p= 28 MPa. After subtracting the heat capacity of a point mass, the remaining heat capacity was successfully decomposed into functional group contributions at all temperatures. The resulting values for the heat capacity contributions of the CH 2, CH 3, and OH groups allow reasonably accurate predictions of the heat capacities of all compounds composed of these groups in this temperature range.