THE MHV2 MODEL - A UNIFAC-BASED EQUATION OF STATE MODEL FOR PREDICTION OF GAS SOLUBILITY AND VAPOR-LIQUID-EQUILIBRIA AT LOW AND HIGH-PRESSURES

MHV2 is a group-contribution equation of state based on the modified Huron-Vidal mixing rule. It combines the SRK equation of state with a model for the excess Gibbs energy, the modified UNIFAC model. The MHV2 model can be used to predict vapor-liquid equilibria (VLE) and gas solubility at low and high pressures. Useful predictions for process calculations can be made over a wide temperature and pressure range. This work considers VLE for mixtures with gases. It describes the main features of the MHV2 model and presents tables containing parameters between 9 modified UNIFAC solvent groups and 13 gases (H-2, O2, N2, CO, CO2, H2S, CH4, C2H2, C2H4, C2H6, C3H6, C3H8, and C4H10). The gas-gas interaction parameters are all assigned the value 0. It is shown that the MHV2 model compares very well with a density-dependent local composition model (DDLC) and the group-contribution equation of state (GC-EOS). Even for complex systems the multicomponent vapor-liquid equilibria are predicted well.