S . M Ghoreishi - aDepartment of Chemical Engineering, Isfahan University of Technology,
H Kamali - aDepartment of Chemical Engineering, Isfahan University of Technology,
H . S Ghaziaskar - bDepartment of Chemistry, Isfahan University of Technology,

Essential oil was extracted from lavender flowers using supercritical carbon dioxide (SC-CO2) via an innovative periodic static-dynamic (PSD) procedure, and semicontinuous (SC) technique. The PSD procedure is composed of two extraction periods of repeated static and dynamic times. Using GC-FID analysis of the extracted samples in conjunction with response surface design, the optimum overall extraction yield (94.4%) was obtained via PSD at 110 bar, 322K, 120 min (static: 8Í15), 16 min (dynamic: 8Í2) in contrast to the 90% extraction yield for the SC at 112 bar, 322K, 22 min (static), 123 min (dynamic). The results indicated that supercritical fluid extraction is a viable technique for separation of constituents such as camphor, fenchone, linalyl acetate, and linalool in which a substantial reduction (74%) in pump and cooler circulator energy consumption and solvent usage is observed in the new PSD method versus the conventional SC method.

Lavender; Supercritical carbon dioxide; Periodic static-dynamic; Response surface design; Essential oil