Prediction of solid solute solubility in supercritical carbon dioxide from PSRK EOS with only input of molecular structure

Using cubic equations of state to predict solid solute solubility in supercritical carbon dioxide requires either sublimation pressures or melting properties to determine the solid phase fugacity of the studied solute in addition to critical properties and the acentric factor. Previous studies have shown that it is viable to estimate critical properties and the acentric factor from group contribution methods or PRCS EOS. However, the issue of lacking experimental melting properties and sublimation pressures remains unsolved. This study proposed combining the PSRK EOS with sublimation pressures estimated from the Lee-Kesler (LK) equation to predict solubility. Both models need identical inputs of critical properties and the acentric factor. For 57 studied solutes, the average logarithmic deviation (ALD-x) of using sublimation pressures from LK with the optimal parameters is 0.84 and similar to that of using experimental melting properties (0.77), demonstrating the feasibility of predicting solubility with only input of molecular structure.