In SC-CO2 extraction,different factors affect the recovery of a target component.
Due to the difficulties of conducting an experiment using high pressure and the need to decrease the number of tests, it was necessary to use an appropriate design of experiment (DOE). Generally, a DOE can decrease the costs and the time of
operation and can be performed in different ways.RSM is the most popular design for an experimental approach, and acentral composite design of the RSM is generally applied in optimization experiments .