Supercritical CO(2) recovery of caffeine from green coffee oil: New experimental solubility data and modeling

The caffeine solubility in supercritical CO(2) Was studied by assessing the effects of pressure and temperature on the extraction of green coffee oil (GCO). The Peng-Robinson(1) equation of state was used to correlate the solubility of caffeine with a thermodynamic model and two mixing rules were evaluated: the classical mixing rule of van der Waals with two adjustable parameters (PR-VDW) and a density dependent one, proposed by Mohamed and Holder(2) with two (PR-MH, two parameters adjusted to the attractive term) and three (PR-MH3 two parameters adjusted to the attractive and one to the repulsive term) adjustable parameters. The best results were obtained with the mixing rule of Mohamed and Holder(2) with three parameters.31613191323Fundacao de Amparo Pesquisa do Estado de Sao Paulo [02/07753-0]Conselho Nacional de Desenvolvimento Cientifico e TccnologicoFundacao de Amparo Pesquisa do Estado de Sao Paulo [02/07753-0