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Moringa oleifera tree is found in many tropical areas, and its seed contains up to 40% of good quality edible oil where sterols are also present. In this work a techno-economic study encompassing the coproduction of oil and sterols from M. oleifeira seeds was accomplished using the RSM–COM approach. The oil is produced by subcritical fluid extraction (SFE) while the purification of the associated sterols is accomplished by a patented technology based on distillation. Besides the expenses and investment associated to the SFE, the respective costs and investment for the preliminary drying of biomass and final separation of sterols from bulk oil were also taken into account. Under optimized extraction pressure and time of 350 bar and 1.3 h, respectively, oil cost was estimated to be 2.76   €   k g oil − 1 for a SFE unit comprising two extractors of 1 m 3 capacity. For the coproduction of sterols with 89.4 wt.% purity, the minimum costs were 5.60   €   k g sterols − 1 . The overall annual production under optimum conditions was 558.9 tons of oil and 1.9 tons of sterols, leading the whole integrated process to a net income of 15.87 M € year −1 . In conclusion the proposed combined process is feasible, and this essay opened the way to exploit M. oleifera by subcritical fluid extraction under the scope of biorefinery premises. [ABSTRACT FROM AUTHOR]

Gac ( Momordica cochinchinensis Spreng) is a traditional fruit from Southeast Asia whose aril oil has been investigated owing to the remarkable abundance of oil and carotenes (e.g. β-carotene and lycopene). In this context, supercritical fluid extraction (SFE) using CO 2 is an option for the exploitation of this raw material. In this work a hybrid approach combining cost of manufacturing (COM) and response surface methodology (RSM) concepts was applied to lab results of SFE of gac oil with the objective of finding the operating conditions that ensure the best technical and economic performance of the process. Upon specifying a SFE commercial process comprising a fruit drying line followed by two extractors of 0.4 m 3 in parallel, the impact of extraction pressure (200–400 bar), temperature (40–60 °C) and time (0.5–2.0 h) on manufacturing costs and productivity was assessed. The best COM for oil extraction was found for 400 bar, 60 °C, and 1.0 h, amounting 8 €   k g oil − 1 . Regarding specifically extraction of carotenes, the best COM was attained for 400 bar, 50 °C, and 1.0 h, amounting 755 €   k g carotenes − 1 . Both production costs are encouraging in relation to current market quotations of gac oil and purified (>90%) carotenes. Finally, a sensitivity analysis to flow rate was accomplished. In the whole, the outcomes of this study support the exploitation of gac oil and naturally occurring carotenes from gac aril through supercritical CO 2 extraction. [ABSTRACT FROM AUTHOR]

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 °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 CO 2 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. [ABSTRACT FROM AUTHOR]