Thermodynamic properties of some organic compounds: I. PVT relationships and calculated thermodynamic properties for normal butanol


  • Grateful acknowledgement is made of financial assistance from the National Research Council.


Pressure-volume-temperature measurements on n-butanol have been carried out using the Kay type of pressure-block apparatus and glass capillary cell. Determinations were made isothermally in the saturated vapor and liquid and superheated vapor regions to above the critical point. Compressibility factors have been calculated. Constants in the Beattie-Bridgman equation of state have been determined from 250° to 300° C. at pressures up to 75 atmospheres.

The thermodynamic properties of normal butanol have been calculated over a temperature range of 0°C. to 300°C. and at pressures up to 1000 lb./sq. in. abs. from the PVT data. Values for the saturated liquid, saturated vapor, and superheated vapor are presented on a pressure-enthalpy diagram with specific volume and entropy as parameters. The entropy of the saturated vapor increases with temperature over a considerable region, indicating a positive specific heat of the saturated vapor in contrast to the lower alcohols of the same series.