MEASUREMENT AND CORRELATION OF THE (PRESSURE, DENSITY, TEMPERATURE) RELATION OF CARBON-DIOXIDE .2. SATURATED-LIQUID AND SATURATED-VAPOR DENSITIES AND THE VAPOR-PRESSURE ALONG THE ENTIRE COEXISTENCE CURVE

Comprehensive measurements of the saturated-liquid and -vapour densities together with the vapour pressure of pure carbon dioxide were carried out from the triple-point temperature (216.580 K) up to about 0.1 K below the critical temperature. The critical constants (Tc = 304.136 K, ρ{variant}c = 467.6 kg · m-3, pc = 7.3773 MPa) and the isothermal compressibilities in the critical region close to the phase boundary were also determined from these measurements. Comparisons with the experimental results of previous studies are presented. Based on the new values of this work, new correlation equations for the vapour pressure, the saturated-liquid density, and the saturated-vapour density have been established. These correlation equations are compared with three current equations of state for carbon dioxide and with several correlation equations for the saturation properties. Furthermore, the influence of condensation in capillaries and pores on the measurements of the saturated-vapour densities is described. © 1990.