TITLE:
A Simplified Method to Estimate the Time Evolution of Oil Extraction from Different Substrates by Supercritical CO2
AUTHORS:
A. Zinnai, F. Venturi, C. Sanmartin, G. Andrich
KEYWORDS:
SFE; Food Grade Oils; Sc-CO2; Microalgae; Seeds; Mathematical Model
JOURNAL NAME:
American Journal of Analytical Chemistry,
Vol.3 No.12A,
December
31,
2012
ABSTRACT: To allow an easy individuation of the
more suitable working conditions (temperature, pressure, flow rate, etc.) to be
adopted to carry out the extraction of food grade oils from different
substrates by supercritical CO2 (Sc-CO2), a simpli- fied kinetic approach has been introduced. This kinetic model was
utilised to describe supercritical fluid extraction (SFE) of oil by Sc-CO2 not
only from seeds (sunflower, soybean and rape) but also from microalgae (Nannochloropsis sp., Schizochytrium sp. and Spirulina (Arthrospira) platensis)
characterised by a lipid fraction with a high proportion of polyunsatured fatty
acids (C20:5w-3; C22:6w-3; C18:3w-6). Thanks to the high affinity
occurring between oil and Sc-CO2 it was possible to introduce a simplified kinetic model
able to describe the time evolution of oil extraction from substrates which
deeply differ for biochemical and biophysical characteristics. Moreover the
synergistic utilisation of the kinetic model introduced and of the Chrastil’s
equation, allowed to predict the time evolution of oil extraction as a function
of the: substrate used; amount of its fat content; mass of substrate charged
inside the extractor; possible pre- treatments carried out on the used substrate; flow rate of Sc-CO2; working conditions
adopted (temperature, pressure and then Sc-CO2 density).