Supercritical fluid extraction of Lavandula stoechas L. ssp cariensis (Boiss.) Rozeira

The flowers of Lavandula stoechas L, ssp. cariensis (Boiss.) Rozeira were e xtracted in both a batch and semicontinuous system by supercritical COB. In the first stage, experiments were performed in a batch system based on res ponse surface methodology (RSM). Parameters used were pressure, temperature , mixing speed and extraction time, and were coded as, X-1, X-2, X-3 and X- 4, respectively. These parameters were investigated at three levels (-1, 0 and 1). The dependent variable, Y, was taken as the volatile concentrate yi eld of supercritical fluid extraction. It was calculated with respect to th e yield of solvent extraction by dichloromethane. In the second stage, expe riments were carried out in a semi-continuous system at constant pressure a nd temperature, and different CO2 flow rates. Concentrations of volatile co mponents were determined as a function of extraction time and CO2 residence time.