| dc.description.abstract | This study aims to understand the accuracy of the Perturbed Chain-Statistical Association Fluid Theory (PC-SAFT) EOS in predicting solubility of drug-like molecules in supercritical carbon dioxide (ScCO2) and compares it with the PR EOS. In PC-SAFT EOS, three pure-component parameters m, σ, ϵ are required for non-associating components, while five pure-component parameters m, σ, ϵ, ϵAB, кAB are required for associating components. These parameters can be regressed by fitting pure-component data such as vapor pressure or liquid density, which is easier to obtain than critical properties. The required critical properties and acentric factor od pure solid solute for PR EOS are determined from group contribution method NRR and PR-COSMOSAC (PRCS) EOS.
In this study, a total of 60 drug-like solid solutes were investigated, and the molecules were divided into 22 non-associating solutes and 38 associating based on whether there were hydrogen bonding functional groups, such as hydroxyl or amino groups, in their molecular structures. For the 22 non-associating systems, there are 13 solutes with vapor pressure experimental data, the average absolute relative deviation (AARD-P) in vapor pressure is 2.53% from PCSAFT, and 48.66% and 60.83% from PR-NRR and PR-PRCS. The overall average logarithmic deviation (ALD-x) in solubility for these 13 solid solutes is 0.29 from PCSAFT and 0.52 and 0.31 from PR-NRR and PR-PRCS, and if the PC-SAFT pure-component parameters were regressed by solubility, the overall average logarithmic deviation (ALD-x) in solubility for 22 solid solutes is 0.22. For the 38 associating systems, the difference of PC-SAFT pure-component parameters кAB=0.01 and кAB=0.02 was also discussed. For 18 solid solutes with vapor pressure, the average absolute relative deviation (AARD-P) in vapor pressure is 8.56% (кAB= 0.01) and 10.78% ( кAB= 0.02) from PC-SAFT, and 88.46% and 189.14% from PR-NRR and PR-PRCS; The overall average logarithmic deviation (ALD-x) in solubility for these 18 solid solutes is 0.49 ( кAB =0.01) and 0.58 ( кAB =0.02) from PC-SAFT and 0.64 and 0.71 from PR-NRR and PR-PRCS, and if the PC-SAFT pure-component parameters were regressed by solubility, the overall average logarithmic deviation (ALD-x) in solubility for 38 solid solutes further reduces to 0.28. In the calculation of vapor pressure, PC-SAFT will have better accuracy; in solubility calculation, for binary systems, if there are binary interaction parameter, PC-SAFT can provide excellent prediction ability, and the ternary system is that PR-NRR has better prediction ability. | en_US |