MODELING OF SOYBEAN OIL BED EXTRACTION WITH SUPERCRITICAL CARBON-DIOXIDE

Dry-milled soybeans are extracted with supercritical carbon dioxide at pressures 270 to 375 atm, temperature 50 to 70‡C, solvent flow rates 0.025 to 0016 cm/sec as a linear velocity in the bed-at supercritical state, and three types of soybean particle size in the range 0.05 to 0.2828 cm. Under these conditions, extraction rates of soybean oil from solid substrates in a fixed bed (1.1 mm I.D. x 200 mm Height) have been determined. The extraction rates were constant during the initial extraction period where the film resistance controls the rates, and then, the rales shifted to time-dependent diffusion controlling mass transfer mode. To correlate these features, mass transfer calculations were carried our for the constant rate period and the subsequent unsteady mass transfer rate period, respectively. © 1990 Korean Institute of Chemical Engineering.