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An Equation of State and Compressed Liquid and Supercritical Densities for Sulfur Dioxide



E. Christian Ihmels, Eric Lemmon, Juergen Gmehling


Densities of sulfur dioxide (SO2) have been measured with a computer-controlled high temperature, high pressure vibrating tube densimeter system (DMA-HDT) in the sub- and supercritical states. The densities were measured at temperatures from 273 to 523 K and pressures up to 35 MPa (311 overall data points), from which a density range between 189 and 1478 kg.m-3 was covered. The accuracy in density measurement was estimated to be better than 0.2 kg.m-3. Using the measured densities and further thermodynamic data from the Dortmund Databank for Pure Component Proper-ties a 12-parameter Helmholtz equation of state was developed for S02. The equation of state is valid from 197.7 to 523 K with pressures up to 3 5 MPa. The uncertainty in density of the equation of state ranges from 0.2% at low temperatures in the liquid and vapor to 0.5% at the highest temperatures. The uncertainty in heat capacities is 2% and the uncertainty in vapor pressure is 0.4%. In the critical region, the uncertainties are higher for all properties except vapor pressure.
Fluid Phase Equilibria
No. 1-2


density, equation of state, sulphur dioxide, thermodynamic properties


Ihmels, E. , Lemmon, E. and Gmehling, J. (2003), An Equation of State and Compressed Liquid and Supercritical Densities for Sulfur Dioxide, Fluid Phase Equilibria (Accessed April 25, 2024)
Created April 30, 2003, Updated October 12, 2021