Utilization of supercritical CO 2 in safflower seed extraction was performed using a semi-batch extractor.
Different
extraction parameters, such as 40–60 MPa pressure, 323–347 K temperature, 20–76 min time,
and
1–3 mL/min CO 2 flow rate were applied. A two-stage experimental design application was performed
in
order to maximize the oil yield. First of all, a 3 2 factorial design was applied to estimate the effect of
the
main factors and their interactions. The second part of the experimental design was improved and
accelerated
using the steepest ascent method. Optimum extraction parameters were determined to be
50
MPa pressure, 347 K temperature and 76 min time at a constant CO 2 flow rate (3 mL/min) according
to
the 2 2 design. Under these conditions, the oil yield obtained was 39.42%, comparable with Soxhlet
extraction
(40%) for 8 h. Shrinking core and empirical kinetic models were applied in order to generalize
the
extraction process. The predicted data was compatible with the experimental data.