Predicting the solubilities of metal acetylacetonates in supercritical CO2: Thermodynamic approach using PC-SAFT

Solubilities of metal precursors in supercritical carbon dioxide (scCO(2)) are needed to effectively design the scCO(2)-based deposition method. Herein, a method for predicting the solubilities of metal acetylacetonate (acac) precursors in scCO(2) was developed using the perturbed-chain statistical associating fluid theory (PC-SAFT) equation of state. Three PC-SAFT pure-component parameters viz., the segment diameter, segment number, and dispersion energy, for two metal acetylacetonates (Cr(acac)(3) and Cu(acac)(2)) were determined by adjusting their values to the measured solubilities in organic solvents. The PC-SAFT parameters of Cr(acac)(3) and Cu(acac)(2) were then applied to predict the experimentally determined metal precursor solubilities in scCO(2) from the literature. The PC-SAFT predictions accurately described the experimental solubilities in scCO(2) over a wide range of pressures and temperatures even if the binary interaction parameter k(ij) was set to 0. The isobaric solubilities in scCO(2) were also calculated with the generalized k(ij) values, which provided a successful PC-SAFT description. (C) 2020 Elsevier B.V. All rights reserved.