Sublimation pressure from solubility data of solids in different supercritical solvents is determined and solvent effects are discussed. Tree binary gas-solid systems containing anthracene, napthalene and phenanthrene as solutes and carbon dioxide, ethane, fluoroform as olvents are considered in the study. The Peng-Robinson equation of state with the mixing rulesproposed by Wong and Sandler are used to evaluate the fugacity coefficient Φ~s that appears in the classical solubility equation which relates the mole fraction of a dissolved solid in a compressed as phase: y=(P~(sub)/PΦs)[exp{(Vs(P-P~(sub))/RT}]. The sublimation pressure P~(sub) of the solid is considered as a parameter to be determined by regression analysis of experimental solubility data (TPy), and theoretically it should be independent of the solvent. Thus, an optimization problem, in which the difference between correlated and experimental solubility is to be minimize, is solved using a method based on genetic algorithms. The results show that the determination of P~(sub) using high pressure solubility data is reliable and produce unique values of sublimation pressure independent of the solvent present in the mixtures.
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