A Simplified Method to Estimate the Time Evolution of Oil Extraction from Different Substrates by Supercritical CO_{2}

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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 CO_{2} (Sc-CO_{2}), a simpli- fied kinetic approach has been introduced. This kinetic model was
utilised to describe supercritical fluid extraction (SFE) of oil by Sc-CO_{2 }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 (C20:5*w**-*3; C22:6*w**-*3; C18:3*w**-*6). Thanks to the high affinity
occurring between oil and Sc-CO_{2} 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-CO_{2}; working conditions
adopted (temperature, pressure and then Sc-CO_{2} density).

References

[1] G. Andrich, U. Nesti, F. Venturi, A. Zinnai and R. Fiorentini, “Supercritical Fluid Extraction of Bioactive Lipids from Microalga Nannochloropsis sp.,” European Journal of Lipid Science and Technology, Vol. 107, No. 6, 2005, pp. 381-386. doi:10.1002/ejlt.200501130

[2] G. Andrich, A. Zinnai, U. Nesti, F. Venturi and R. Fiorentini, “Supercritical Fluid Extraction of Oil from Microalga (Arthrospira) platensis,” Acta Alimentaria, Vol. 35, No. 2, 2006, pp. 195-203.
doi:10.1556/AAlim.35.2006.2.6

[3] A. Zinnai, U. Nesti, F. Venturi, G. Andrich and R. Fiorentini, “Estrazione in Fase Supercritica di Olio da Schizochytrium sp.,” Rivista Italiana Delle Sostanze Grasse, Vol. 83, No. 1, 2006, pp. 1-5.

[4] G. Andrich, S. Balzini, A. Zinnai, V. De Vitis, S. Silvestri, F. Venturi and R. Fiorentini, “Supercritical Fluid Extraction in Sunflower Seed Technology,” European Journal of Lipid Science and Technology, Vol. 103, No. 3, 2001, pp. 151-157.
doi:10.1002/1438-9312(200103)103:3<151::AID-EJLT151>3.0.CO;2-T

[5] G. Andrich, A. Zinnai, S. Nottoli , F. Venturi and R. Fiorentini, “A Mathematical Model Describing the Supercritical Fluid Extraction (SFE) of Oil from Soybean Seeds,” Chemical Engineering Transactions, Vol. 2, 2002, pp. 397-401.

[6] G. Andrich, A. Zinnai, F. Venturi and R. Fiorentini, “A Mathematical Model Describing the Supercritical Fluid Extraction (SFE) of Rapeseed (Brassica Napus) Oil,” Chemical Engineering Transactions, Vol. 3, 2003, pp. 1605-1610.

[7] J. M. Del Valle and J. C. De La Fuente, “Supercritical CO2 Extraction of Oilseeds: Review of Kinetic and Equilibrium Models,” Critical Reviews in Food Science and Nutrition, Vol. 46, No. 2, 2006, pp. 131-160.
doi:10.1080/10408390500526514

[8] E. L. G. Oliveira, A. J. D. Silvestre and C. M. Silva, “Review of Kinetic Models for Supercritical Fluid Extraction,” Chemical Engineering Research and Design, Vol. 89, No. 7, 2011, pp. 1104-1117.
doi:10.1016/j.cherd.2010.10.025

[9] H. Sovová, “Steps of Supercritical Fluid Extraction of Natural Products and Their Characteristic Times,” The Journal of Supercritical Fluids, Vol. 66, 2012, pp. 73-79.
doi:10.1016/j.supflu.2011.11.004

[10] I. Zizovic, M. Stamenic, A. Orlovic and D. Skala, “Supercritical Carbon Dioxide Essential Oils from Plants with Secretory Ducts: Mathematical Modelling on the Micro-Scale,” The Journal of Supercritical Fluids, Vol. 39, No. 3, 2007, pp. 338-346.
doi:10.1016/j.supflu.2006.03.009

[11] M. Stamenic, I. Zizovic, A. Orlovic and D. Skala, “Mathematical Modelling of Essential Oil SFE on the Micro-Scale-Classification of Plant Material,” The Journal of Supercritical Fluids, Vol. 46, No. 3, 2008, pp. 285-292. doi:10.1016/j.supflu.2008.03.007

[12] L. Fiori, D. Basso and P. Costa, “Supercritical Extraction Kinetics of Seed Oil: A New Model Bridging the ‘Broken and Intact Cells’ and the ‘Shrinking-Core’ Models,” The Journal of Supercritical Fluids, Vol. 48, No. 2, 2009, pp. 131-138. doi:10.1016/j.supflu.2008.09.019

[13] H. Sovová, “Modelling the Supercritical Fluid Extraction of Essential Oil from Plant Materials,” Journal of Chromatography A, Vol. 1250, 2012, pp. 27-33.
doi:10.1016/j.chroma.2012.05.014

[14] J. Chrastil, “Solubility of Solids and Liquids in Supercritical Gases,” Journal of Physical Chemistry, Vol. 86, No. 15, 1982, pp. 3016-3021. doi:10.1021/j100212a041

[15] F. Favati, R. Fiorentini and V. de Vits, “Supercritical Fluid Extraction of Sunflower Oil: Extraction Dynamics and Process Optimisation,” Proceedings of the 3rd International Symposium on Supercritical Fluids, Strasbourg, 17-19 October 1994, pp. 305-309.

[16] Z. Yu, B. Sing, S. H. Risvi and J. A. zollweg, “Solubilities of Fatty Acids, Fatty Acid Esters, Triglycerides and Fats and Oils in Supercritical Carbon Dioxide,” Journal of Supercritical Fluids, Vol. 7, No. 1, 1994, pp. 51-59.
doi:10.1016/0896-8446(94)90006-X

[17] R. L. Mendes, A. Reis, H. L. Fernandes, J. M. Novais and A. F. Palavra, “Supercritical CO2 Extraction of Lipids from a GLA-Rich Arthrospira (Spirulina) maxima Biomass,” Proceedings of the 5th Iternational Conference on Supercritical Fluids and Their Applications, Verona, 13-16 June 1999, pp. 209-216.