Supercritical Carbon Dioxide Impregnation of Polymers: experimental Results and Modelling.

The impregnation of an anti-inflammatory drug, nimesulide, on chemically cross-linked PVP and on physically-linked PVP has been performed using supercritical carbon dioxide as solvent and operating at 313.15 and 333.15 K and pressures ranging from 130 to 220 bar. The experimental impregnation curves representing the impregnated quantity of drug versus time have been modelled using differential mass balances for the fluid and the solid phases. A simple model based on the assumptions of negligible axial dispersion and plug flow regime in the column was used to correlate the experimental data.