In general, phase equilibrium information is necessary to implement supercritical fluid technology (SFT) 6, 7, 9. Although, several supercritical fluids are utilized as solvent in process industry, ScCO 2 is the most desirable solvent 8, 13, 14, 15, 16, 17. The major applications are in drug particle micronization, food processing, textile dyeing, ceramic coating, extraction and many more 4, 6, 7, 8, 9, 10, 11, 12. ScCO 2 has been used as a solvent in various process applications, because it has gas like diffusivity and liquid like density with low viscosity and surface tension 1, 3, 4, 5. It has physical properties (density, diffusivity, viscosity and surface tension) intermediate to that of gas and liquid 1, 2. Supercritical carbon dioxide (ScCO 2) is a fluid above its critical point. Finally, total, sublimation and solvation enthalpies of empagliflozin were calculated. The RKEoS + KMmr was observed to correlate the data with 8.07% (correspond AIC c is − 635.79). Among density-based models, Bian et al., model was the best and corresponding AARD% was calculated 5.1. Further, the measured data was also correlated with 11 existing (three, five and six parameters empirical and semi-empirical) models and also with Redlich-Kwong equation of state (RKEoS) along with Kwak-Mansoori mixing rules (KMmr) model. The proposed model correlated the data with average absolute relative deviation (AARD) and Akaike’s information criterion (AIC c), 7.22% and − 637.24, respectively. A new solubility model was derived to correlate the solubility data using solid–liquid equilibrium criteria combined with Wilson activity coefficient model at infinite dilution for the activity coefficient. The cross over region was observed at 16.5 MPa. The measured solubility in terms of mole faction ranged from 5.14 × 10 –6 to 25.9 × 10 –6. The solubility of empagliflozin in supercritical carbon dioxide was measured at temperatures (308 to 338 K) and pressures (12 to 27 MPa), for the first time.

Supercritical carbon dioxide formula