Solubility prediction in supercritical CO2 using minimum number of experiments

The correlation ability and solubility prediction in supercritical carbon dioxide of a proposed equation were studied. The world. involved the solubilities of nicotinic acid and p-acetoxyacetanilide in supercritical carbon dioxide using a dynamic flow solubility system at 35-75degreesC and 100-200 bar. The generated experimental solubility data together with 21 data sets collected from the literature were used to evaluate the correlation ability of available empirical equations. The average absolute relative deviations (AARD) for the empirical equations are 12.6-24.8%. The prediction capability of the modified empirical relationship was studied with six experimental data points as a training set. Then, solubility at other temperatures and pressures were predicted. The AARD between predicted solubilities and observed values is 17%. (C) 2002 Wiley-Liss, Inc. and the American Pharmaceutical Association.