Measurement and correlation of flavanone, tangeritin, nobiletin, 6-hydroxyflavanone and 7-hydroxyflavone solubilities in supercritical CO2

•Solubilities of five flavonoids measured, (313-333) K.•Flavanone, tangeritin, nobiletin, 6-hydroxyflavanone and 7-hydroxyflavone.•Assessment with Mendez-Santiago-Teja (MST) consistency test.•Correlation with entropy-based solubility parameter (eSP) model.•Generalized form of the MST equation for flavonoids.

Solubilities of five flavonoids (flavanone, tangeritin, nobiletin, 6-hydroxyflavanone and 7-hydroxyflavone) were measured in supercritical CO2 at (313.2-333.2) K and at pressures up to 22 MPa. Among the solubility values of the flavonoids at 313 K, that of flavanone was the highest (∼10−3 mol/mol) next to that of tangeritin and nobiletin which had almost the same range of solubility values (10−6-10−5), followed by 6-hydroxyflavanone (∼10−7) and 7-hydroxyflavone (∼10−8). Data had a maximum average relative deviation (ARD) of 1.69% from the Mendez-Santiago-Teja (MST) consistency test. The solubility of each flavonoid was correlated with the Peng-Robinson, entropy-based solubility parameter and a generalized form of the MST equation to within 3% ARD.

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