Economical Analysis of a Pressurized Fluid-Based Process Applied for Phytochemicals Recovery in a Sustainable Biorefinery Concept for Brazilian Ginseng Roots

Abstract

A growing number of technologies are being developed in order to produce different high added value products, such as phytochemicals, ethanol and other chemicals from biomass, representing an important trend that needs to be evaluated. The use of pressurized-fluid technologies to obtain phytochemicals from certain biomasses has shown encouraging results in terms of selectivity, enabling its use prior bioenergy generation since generally only a small part of the solid material is extracted. The phytochemical compound which is most financially interesting to extract from the Brazilian Ginseng (Pfaffia glomerata) roots is ecdysterone (ß-ecdysone), an ecdysteroid. Ecdysteroids are a class of natural steroids acting as hormones and ß-ecdysone is the most important steroid employed in cosmetic formulations. It is also used in other industries such as the food and pharmaceutical industry. Due to its health properties, large amounts of Pfaffia glomerata roots are being exported from Brazil to countries that use phytochemical therapies widely. This work is part of a project that aims to present a solution to perform phytochemicals recovery step in Brazil envisioning decentralized local-scale production. In this study, first the influence of the extraction temperature (353–413 K) and static extraction time (5–15 min) using pressurized ethyl acetate as extracting solvent on the ß-ecdysone recovery was experimentally evaluated and compared with literature results employing other pressurized fluids. Afterwards, an economical analysis was done for comparison using ASPEN PLUS software and OSMOSE platform. It was observed that the relationship of the ß-ecdysone recovery, extraction temperature and static extraction time was linear. An increase in temperature and static time resulted in enhancement of the ß-ecdysone recovery from the biomass. On the other hand, the increase of the extraction temperature beyond 373 K possibly might enhance the degradation of the ß-ecdysone extracted decreasing its relative amount in the extract. Since for the economical analysis performed the former response variable (ß-ecdysone recovery) is most important than the latter, it was calculated the net present value of this process considering high extraction temperatures. Considering an installation time of two years, a lifetime of 25 years and an interest rate of 15 % the obtained net present value for the different pressurized extracting solvents were in the following order: ethyl acetate > ethanol > CO2-ethanol mixture. The results demonstrate that the inclusion of a pressurized fluid-based process using ethyl acetate or ethanol for ß-ecdysone recovery prior further bioenergy production is very promising.