Journal of Chemical and Engineering Data, Vol.54, No.11, 3034-3036, 2009
Solubility of 1,3-Dimethyl-7H-purine-2,6-dione (Theophylline) in Supercritical Carbon Dioxide
This contribution provides complementary experimental data of solubility (y(2), molar fraction) of solid 1,3-dimethyl-7H-purine-2,6-dione (theophylline) in supercritical CO(2) as a function of temperature (313 K <= T <= 333 K) and pressure (10 MPa <= P <= 44 MPa). A static-analytic methodology was used with standard deviations from average solubility measurements of <= 38% and with estimated inherit errors <= 25%. The solubility of theophylline increased with the CO(2) density from 0.33.10(-5) mol.mol(-1) at 797.2 kg.m(-3) (313 K, 16 MPa) to 3.3.10(-5) mol.mol(-1) at 890.2 kg.m(-3) (333 K, 40 MPa). The solubility increased with pressure and temperature. Experimental solubilities were correlated with a density-based model with three adjustable parameters, which was valid for solvent densities in the range of (400 to 950) kg.m(-3).