Representing experimental solubility of phenylephrine hydrochloride in supercritical carbon dioxide and modeling solute solubility using semi-empirical correlations

Phenylephrine is used as a decongestant sold as an oral medicine, as a nasal spray, or as eye drops. Phenylephrine is now the most common over-the-counter decongestant in the United States. In this regard, measuring the solubility of phenylephrine hydrochloride seems applicable in supercritical carbon dioxide-based processes dealing with this drug. The obtained solubility data obtained by a static method coupled with gravimetric method were in the range of 1.01 × 10−4 to 2.89 × 10−3 based on the mole fraction at the different temperature and pressure ranges of 308.15–338.15 K and 160–400 bar, respectively. In addition, the solubility data were used to obtain the adjusting parameters of semi-empirical correlations namely Kumar and Johnston, Bartle et al., Chrastil and Mendez-Santiago-Teja using a simple data regression.

The self-consistency tests for the four used semi-empirical correlations (a) MST model, (b) Bartle et al., (c) K–J model and (d) Chrastil model (○ is 308.15 K isotherm, □ is 318.15 K isotherm, x is 328.15 K isotherm, ● is 338.15 K isotherm, dashed line is the correlated solubilities by correlations, y is the mole fraction and S the solubility of phenylepherin hydrochloride).Figure optionsDownload as PowerPoint slideHighlights
► Phenylephrine hydrochloride solubility id supercritical carbon dioxide was measured.
► To measure the solubility static method coupled with gravimetric method was used.
► Phenylephrine hydrochloride solubility was between 1.01 × 10−4 and 2.89 × 10−3 mole fraction.
► Four correlations were used to correlate measured phenylephrine hydrochloride solubility.
► Results also revealed rather a good extrapolative capability of the used correlations.