abstract
The supercritical fluid extraction (SFE) of Eucalyptus globulus deciduous bark is investigated, under the context of biorefinery, aiming at the definition of a pathway for the production of enriched extracts in triterpenic acids (TTAs). Scale-up studies are performed, well supported by modeling and by experiments carried out at lab, intermediate and pilot scales (0.5, 5.0 and 80.0 L, respectively). By acknowledging the significant role played by cosolvent (ethanol) addition on the concentration of TTAs, extraction curves are measured at 200 bar and 40 degrees C, using two different ethanol contents, 2.5% and 5.0% (wt). Taking into account the results achieved by four distinct models, the intraparticle diffusion is confirmed as the prevailing mass transfer resistance in both conditions. Accordingly, the ratio between CO2 flow rate and biomass weight is adopted as scale-up criterion. Despite the geometric differences between the three units, the measured extraction yields and TTAs concentration evidence good agreement, which validates the established scale-up rule. In the whole, our results legitimate the technical viability of the SFE of E. globulus deciduous bark for future exploitation at larger scales. (C) 2014 Elsevier B.V. All rights reserved.
keywords
DIFFUSION-COEFFICIENTS; CARBON-DIOXIDE; CO2 EXTRACTION; SEED OIL; EXPERIMENTAL-DESIGN; ECONOMIC-EVALUATION; MATHEMATICAL-MODEL; BIOMASS RESIDUES; OUTER BARKS; FRACTIONATION
subject category
Chemistry; Engineering
authors
de Melo, MMR; Domingues, RMA; Sova, M; Lack, E; Seidlitz, H; Lang, F; Silvestre, AJD; Silva, CM
our authors
Armando Jorge Domingues Silvestre
Full professor
Carlos Manuel Silva
Associate Professor
Marcelo Morais Rodrigues de Melo
Post-Doc Fellowship
Projects
acknowledgements
This project has received funding from the European Union Seventh Framework Programme (FP7/2007-2013) under grant agreement no. CP-IP 228589 AFORE. Authors acknowledge also Associate Laboratory CICECO (Pest-C/CTM/LA0011/2013).