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Supercritical fluid extraction assisted by cold pressing (SFEAP) is presented for obtaining volatile oil from clove buds at 150 bar, 40 °C, and using two torques (40 and 80 N.m). As the best condition, SFEAP with 40 N.m provided an oil yield of 22.19 g/100 g buds containing Eugenol (57.7 wt.%), Eugenyl Acetate (12.6 wt.%), β-caryophyllene (8.3 wt.%), and α-humulene (0.9 wt.%). This paper also presented, for the first time, the economic evaluation of using SFEAP instead of SFE. In the economic approach, 24 scenarios were tested in the terms of cost of manufacturing (COM), which consisted of evaluating the scale of the plant, capital financing, purchasing cost of clove, solvent to feed mass ratio and the extraction techniques. The best scenario indicated a COM of only US$ 13.42/kg oil, whereas approximately 87% of the COM is dependent on the purchase cost of clove and other materials.

Supercritical fluid extraction assisted by pressing (SFEAP) and supercritical fluid extraction (SFE) were compared in terms of extraction kinetics and extract fractionation using fennel. Extraction was performed at a pressure of 200 bar, a temperature of 40 °C, and a solvent-to-feed ratio of 95, using torques of 0, 40, and 70 N m. The overall extraction yield increased by 24.5%, from 9.8 g extract/100 g fennel for SFE to 12.2 g extract/100 g fennel for SFEAP with a torque meter reading of 40 N m, while overall extraction yield increased by only 2.5% after increasing the torque from 40 N m to 70 N m. In the second part of this study, fennel oils extracted with SFE and SFEAP were successfully fractionated into fatty oil rich product and essential oil rich product using two serial, equal-sized separators.

This paper presents the techno-economic influence of grinding time (GT) (10 s–90 s) and CO2 flow rate (FR) (1.08 × 10−4–2.17 × 10−4 kg/s) on the supercritical fluid extraction (SFE) performance of oil from pequi (Caryocar brasiliense) under 60 °C and 40 MPa. Then, in the economic approach, the best extraction curves were described in terms of Cost of Manufacturing (COM) in the laboratory scale for each combination of GT and FR for selecting the suitable mass to feed mass ratio (S/F) that yielded the lowest COM and the highest productivity. Thereafter, with this S/F, eight scenarios were tested in pilot (100 L) and industrial (500 L) scales with CO2 recycle, which included the purchase cost of pequi and acquisition cost of equipment. Within these eight scenarios tested, the most promising one indicated a COM of only US$ 37.03/kg pequi oil, whereas approximately 85% of the COM is dependent on the purchase cost of pequi and other raw materials (e. g., CO2).

Extraction processes that employ supercritical fluid technology has been extensively applied for the obtaining of high-quality extracts from turmeric rhizomes. Nevertheless, these processes generate high quantities of wastes, which are potential sources of antioxidant constituents and carbohydrates. In this work, mixed biopolymers composed of starch and curcuminoids were recovered from supercritical fluid and pressurized liquid extraction processes. The quality of these materials was investigated in terms of experimental and economic approaches. The application of supercritical fluid and pressurized liquid extraction resulted on products with relevant quality in terms of curcuminoids and modified polymer matrix, which can attribute inclusion in industry as a colorant agent, and in human diet as a resistant starch source. Economic evaluation reports that recovery of biopolymers from turmeric wastes is a feasible alternative considering 80% yield and capacities of 50 L and 500 L.

Phytochemicals extracted from natural sources are widely studied for many applications, including the prevention of diseases and functional foods. In this context, passion fruit by-products (PFBP) can play an important role in obtaining these compounds. This work aimed to concentrate PFBP extracts from supercritical fluid extraction (SFE) (fixed at 40 °C and 35 MPa) in δ-tocotrienol, β/γ-tocotrienol, squalene, and carotenoids using a homemade fractionation system with two separator vessels. Integrated extraction and fractionation (SFE-SFF) were performed at 17−25 MPa and 50−80 °C. An economic evaluation simulated a pilot-scale process, resulting in a cost of US$ 277–384/kg extract for the most concentrated fraction (F2). Two SFE-SFF conditions were able to concentrate squalene in about 5.2 times in the last fraction of the process (F3). In contrast, the proposed integrated process did not seem promising to concentrate carotenoids, thus other fractionation methods should be investigated.

The effect of grinding time (GT) from 15 s to 20 min on the dynamic yield of supercritical fluid extraction (SFE(from fennel was investigated. The extractor was subjected to a pressure of 200 bar, a temperature of 313 K, and a supercritical CO2 flow rate of 2.0 × 10−4 kg/s over 80 min. It was found that the overall SFE yield was increased from 6.4 g/100 g fennel when GT = 15 s to 9.8 g/100 g fennel when GT =6 min, while it changed by only 1.5 g/100 g fennel after increasing GT from 6 min to 20 min. The process was then modeled based on the mass conservation law, and the model was solved using Galerkin’s method on finite element method (FEM). It was demonstrated that considering the whole bed as one single element can acceptably solve the PDEs and reduces the computation cost significantly.

The present work describes setting up a laboratory unit for supercritical fluid extraction. In addition to its construction, a survey of cost was done to compare the cost of the homemade unit with that of commercial units. The equipment was validated using an extraction of annatto seeds’ oil, and the extraction and fractionation of fennel oil were used to validate the two separators; for both systems, the solvent was carbon dioxide. The chemical profiles of annatto and fennel extracts were assessed using thin layer chromatography; the images of the chromatographic plates were processed using the free ImageJ software. The cost survey showed that the homemade equipment has a very low cost (~US$ 16,000) compared to commercial equipment. The extraction curves of annatto were similar to those obtained in the literature (yield of 3.8% oil). The separators were validated, producing both a 2.5% fraction of fennel seed extract rich in essential oils and another extract fraction composed mainly of oleoresins. The ImageJ software proved to be a low-cost tool for obtaining an initial evaluation of the chemical profile of the extracts.