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A novel process for the purification and recycling of CO2 (PRCO2) in a pilot scale unit was implemented and validated. The system is a 4-cycle pseudocontinuous process composed of on-line supercritical fluid extraction integrated with fractionation of extracts in three separation vessels, followed by purification of CO2 in adsorption column at subcritical conditions, and subsequent recycling of the purified CO2 with the aid of a storage tank. Turmeric and annatto were the plant matrices used for extraction and oat bran was used as adsorbent. The PRCO2 reduced the consumption of CO2 in 85.24% for annatto and 74.27% for turmeric, representing monetary savings of USD 186.40 and USD 111.83, respectively. Economical evaluation showed that the increasing of the number of cycles decreased the cost of manufacture from USD 349.60/kg to 122.67/kg for the processing of annatto and USD 91.31/kg to USD 36.56/kg for the processing of turmeric.

This study evaluates the integration of supercritical fluid extraction process to obtain sugarcane wax extract from the sugarcane filter cake residue. This cake is eliminated from the decantation process of sugarcane juice in the sugarcane biorefinery and it is generally used as a fertilizer. From this cake a lipophilic material, containing long-chain fatty alcohols and phytosterols, can be selectively recovered by means of the use of supercritical CO2 as extracting solvent. Aspen Plus® software was used to simulate the sugarcane biorefinery producing electricity, conventional and cellulosic ethanol and wax extract. A thermal-economic model was developed in Matlab software to perform energy integration and the economic analysis of this novel biorefinery concept. The results showed that by increasing temperature and pressure of the extraction process it is possible to produce more wax extract at an overall lower investment as lower extraction time is necessary, decreasing the number of extractors working in parallel. The integration of the extraction process to the sugarcane biorefinery had no impact on the overall ethanol production and had small impact on the electricity available for sale to the grid, decreasing only around 3% the net electricity. Payback time is strongly reduced by this integration strategy, decreasing 74% when the best configuration for SFE is adopted. The selling price for the wax extract strongly influences on the economic viability of this process, indicating that the integration of this extraction process to the sugarcane biorefinery is only economic attractive if the wax extract selling price is higher than 26.5 USD/kg.

The sugarcane sector in Brazil has undergone a major modernization in the last thirty years. Embracing the biorefinery concept, this sector is investigating bioproduct diversification and mostly putting a lot of effort and investment on second generation ethanol production. In this context, the investigation of the integration of a third generation biofuel production using microalgae to the sugarcane biorefinery seems an important starting point. This study evaluates the integration of microalgae growth and processing to a sugarcane biorefinery producing first and second generation ethanol using process simulation tools. Microalgae are cultivated using CO2 produced during fermentation of ethanol and it is processed using supercritical fluid extraction technology in order to obtain lipids rich in high added-value compounds, carotenoids. The results showed that the integration of microalgae biomass processing without previously drying with the sugarcane biorefinery is not attractive from the thermo-economic point. When considering the extraction of dried microalgae the extraction process could be thermal integrated to the sugarcane biorefinery producing ethanol without the need of buying external fuel. The amount of CO2 used as solvent to the supercritical fluid extraction was the main factor that influenced the economic viability of the process. When microalgae pretreatment by cell disruption or co-solvent extraction was considered, it was possible to decrease the amount of CO2 used in the process and an increase in process yields was consequently achieved. The use of a co-solvent in the extraction increased in 1.4 and 2.4 times lipids and carotenoids extraction, respectively, and presented a lower investment when comparing with microalgae extraction without cell disruption.

This study presents a thermoeconomic and environmental assessment of the extraction of lipids and proteins from wet microalgal biomass in a 3G biorefinery by two different technologies: supercritical fluid extraction (SFE) and low-pressure solvent extraction (LPSE). Simulation tools were used to study a sugarcane biorefinery producing ethanol from sugarcane juice (1G) and bagasse (2G); the microalgal growth in an open pond; and the processing of microalgal biomass into lipids, proteins and synthetic natural gas (SNG). Supercritical water gasification (SCWG) of microalgal biomass enables an increase in biofuel production of 10.2% MJ when no extraction process is considered and of 1.9% MJ when LPSE is considered. The heat demand of the proposed biorefinery with LPSE was increased by 87.8% compared with the demand of the sugarcane biorefinery without microalgal growth and processing. When the SFE process is considered, the heat demand of the overall process increased 3.2 times. SFE for wet microalgae processing is not economically attractive, as it increases the total investment by 71%. The CO2 flow used in the SFE process demonstrated to be a key factor in the thermoeconomic viability of the process. Regarding the wet processing of microalgae prior to SCWG, the best alternative studied was the use of LPSE technology.

The use of supercritical CO2 (SC–CO2) antisolvent for micronization, coprecipitation, and fractionation of high-value products for biorefining of plant matrices into marketable products has been a promising and increasing research topic. These SC–CO2 antisolvent processes are able to microencapsulate many materials that are difficult to treat with conventional techniques. In addition, the control of the morphology of materials by adjusting nucleation and growth during particle production is provided. The use of supercritical antisolvent processes is advantageous when compared with other methods like freeze-drying, drying at high temperatures and spray-drying such as uniform particle size distribution in the products and high efficiency to obtain nano or microparticles. The optimization of the process on the yield and quality of obtained particles properties depend mainly on the operational conditions such as pressure, temperature, and concentration of the bioactives solution, in terms of extract and polymer. Thus, this chapter provides some insights about the fundamentals and effects of operational conditions of these SC–CO2 antisolvent processes.

The use of supercritical CO2 (SC–CO2) as a solvent for the extraction of vanillin from organosolv media was proposed and evaluated. The use of sugarcane bagasse as a biomass source to product diversification has been gaining much attention recently and it is a very promising research topic. From sugarcane bagasse, it is already produced fuels as 2G ethanol and others are being investigated as methanol, SNG. Also, different bioproducts as PET area already in the market and bioproducts as xylitol, vanillin, etc. are under study or investigated in pilot plants. Thus, in this chapter, some perspectives on vanillin production from sugarcane bagasse lignin using supercritical CO2 as a solvent in a novel integrated second-generation ethanol biorefinery are presented.

This chapter proposes an innovative biorefinery conceptual process for the production of carotenoids from microalgae using lignocellulose-based biorefinery products and/or by-products and pressurized fluids. The extraction process, which can be done also with microalgal biomass with high content of moisture avoiding high-cost downstream processes, involves the use of ethanol and 2-MethylTetraHydroFuran (2 MTHF) mixed or in a sequential form for selective extraction of carotenoids. 2 MTHF is obtained from furfural, which is produced as a by-product during lignocellulosic biomass (sugarcane bagasse, wood, corn stover, rice straw, etc.) pretreatment for ethanol production, for example. The solvent recovery step involves the use of CO2, which is obtained from ethanol fermentation as a by-product. Specific conditions for CO2 for temperature and pressure to achieve supercritical conditions would be applied in order to besides high solvent recovery and recycling provide a desirable selective carotenoid purification and encapsulation if a coating material is added. The two-step process can be converted in a one-step process minimizing carotenoid degradation if the extraction process is performed under higher pressure than that performed during extract precipitation. In addition, the proposed processing route can be well integrated into conventional existing biofuels production (gasification, combustion, etc.) scenarios using the solids recovered after carotenoids production as feedstock.

This chapter discusses the recent (2013–2018) applications on the use of supercritical CO2 (SC–CO2) antisolvent for micronization, coprecipitation, and fractionation of high-value products for the food, cosmetic, and pharmaceutical industries, most focusing on the applications of integrated techniques on the biorefining of plant matrices into marketable products using supercritical carbon dioxide as an antisolvent. The concept of the biorefinery is defined as sustainable processing of feedstocks for bioenergy and biochemical purposes resulting in various marketable products, such as natural dyes, antioxidants, proteins for food and feed, lipids for biodiesel, and carbohydrates as feedstock for bioethanol production

This work investigates a novel approach for turmeric rhizomes valorization for the obtaining of microparticles composed of curcuminoids ethanolic extract and fractionated volatile oils, using compressed carbon dioxide as an antisolvent and the recovery of phenolic compounds and carbohydrates with pressurized hot water. In addition, a cheap and versatile method for the quantification curcuminoids using thin-layer chromatography coupled to image processing analysis was applied to the solid wastes and liquid extracts from turmeric, derived from extraction processes which employed supercritical CO2 and pressurized liquid ethanol. Coprecipitation of PEG with compressed CO2 resulted in the formation of spherical particles and blocks of aggregates. The reaction with vanillin-sulfuric acid reagent favored the detection of curcuminoids with a reasonable sensibility and wide linear range and mean recoveries between 92 and 104%.

It is presented a technical and economic analysis of ammonia borane confined in silica aerogel using carbon dioxide at subcritical conditions. The process was simulated in Aspen Plus software and an economic analysis was carried. The results showed that it is possible to produce 4795 kg/year of products with a total investment of 1.32 MUSD and a cost of manufacturing per mass of product of 183 USD/kg fixing the ageing time to 5 days. The results indicated that microparticles residence time is a restrictive factor of the process as it limits the number of process cycles in a year. According to new experiments, it is possible to reduce time from 5 days to 2 days. This implies the decrease in the cost of manufacturing to 87 USD/Kg with the same total initial investment and a rise in the annual productivity to almost 12 t/year.

Supercritical fluid extraction has been employed as a green alternative for the obtaining of extracts provided of bioactive constituents from defatted Assai waste. The effects of process parameters on the resulted overall extraction curves were evaluated using a spline model, which adjustable parameters used to analyze the extraction behavior were the time span periods for the constant and falling extraction rates, i.e., tCER and tFER, and the extraction rate for the constant extraction period, MCER (or b1). The mathematical modeling was performed using an alternative algorithm implemented in MS Excel, which was able to provide reliable fittings comparable to SAS software. Although no report has been found to be compared to our economic evaluation findings, the costs of manufacturing (26.20–4.88 USD/kg extract) obtained in this work are competitive in the market, since the selling price of similar products worldwide is over 80.00 USD/kg of extract.

In this study, we discuss the difference regarding thermo-economic and environmental (water intake) aspects between two methods of biomass hydrolysis. A thermo-economic model was developed using Aspen Plus® and MATLAB software in order to analyze the energy efficiency, as well as, the economic impact of the hydrolysis process integrated into a traditional ethanol production process from sugarcane. The study aimed at comparing the enzymatic route for sugarcane bagasse ethanol production with the supercritical water-based one. The use of supercritical water hydrolysis (SCWH) process showed promising results, being the process energetically self-sufficient when considering pumping of liquid streams with biomass content of 20% and the decompression of the steam separated after SCWH with a turbine, in order to produce electricity. In terms of economics, the biorefinery concept using enzymatic route presented the highest production costs due to the higher total investment cost and the cost for the raw materials, which is 14% higher than the biorefinery with SCWH, giving a payback time for the investments of 7.5 years, meanwhile 6.2 for the SCWH route. Also better results were obtained for water intake for the SCWH option, being lower than the maximum permitted for a new investment on the Brazilian sugarcane sector.

The present study evaluates a sugarcane biorefinery producing ethanol through juice fermentation and methanol via gasification of sugarcane lignocellulosic residues and liquid fuel synthesis. Two technologies of gasification named entrained flow and circulating fluidized bed are compared. Flowsheet modeling and thermo-economic analysis methods are applied, followed by a multi-objective optimization based on a genetic algorithm. The optimum Ethanol–Methanol biorefinery design options are compared with other previously studied sugarcane biorefineries. The results show that the biorefinery's energy efficiency increases significantly with the integration of a methanol production plant in a conventional ethanol distillery. The configuration using an entrained flow gasifier presents lower conversion efficiency than the one using a circulating fluidized bed gasifier. However, for the entrained flow gasifier configuration, the size of the methanol production process could be bigger since more heat is available for the ethanol process favouring the integration with the ethanol plant. Higher energy efficiency due to increase of methanol production leads to a higher total investment for both gasification technologies. The cost analysis shows that the calculated methanol production cost is 30% higher than its current market price. Environmental incentives for biofuels could change this scenario but are not in the scope of this study.

The present study aims at studying the supercritical water gasification (SCWG) of leftover Brazilian ginseng roots after phytochemicals extraction for synthetic natural gas (SNG) production, envisioning the development of a promising Brazilian ginseng roots valorization using sub/supercritical fluids in different steps. A multi-objective energetic-economic-environmental optimization of the proposed SCWG process was assessed through the use of computational simulation tools. The results showed that, for a given leftover biomass input of 20MW, a specific cost of 62-66 USD/MWh of SNG is obtained, which is higher than the average price on the Brazilian market. On the other hand, the production process of SNG from this residue showed to be a promising option, being energetically self-sufficient and environmentally friendly. In order for this alternative process to become more economically attractive we proposed the construction of the SCWG and the sub/supercritical extraction units in the same location, sharing part of the same high-pressure equipment.

Quercetin is an antioxidant compound with promising activity against a wide variety of diseases. However, a major limitation for the clinical application of quercetin is its low bioavailability, due to its low solubility in water. One way to increase the bioavailability of quercetin is to precipitate it in sub-micrometricscale, encapsulated by a surfactant material, using the Supercritical Fluid Extraction of Emulsions (SFEE) method. The objective of this work is to study the scale-up of a semi-continuous SFEE process for the production of microencapsulated quercetin. An experimental study of the encapsulation of quercetin in soy-bean lecithin–Pluronic L64®surfactants was performed in order to evaluate the variation of product characteristics with significant parameters, such as duration of SFEE, density of CO2 medium, used CO2/L of emulsion (kg/L), and thus determine the suitable conditions for scale-up. In addition, a themo-economic evaluation was done in order to identify bottlenecks during scale-up and promote solutions. According to the thermo-economic evaluation, the decrease of CO2 flow demonstrated to be the main parameter to decrease the energy demand and cost of manufacturing of the SFEE process. Thus further experimental studies should be done towards optimization of this parameter.

Chitosan is a natural polymer largely studied for heavy metal adsorption applications, since the amino and hydroxyl groups present in its structure can act as chelation sites. However, this material presents some drawbacks as adsorbent due to its low mechanical strength. Studies have shown that the use of immobilized chitosan on glass beads can improve the mechanical strength of adsorbent and enhance mass transfer properties. For this reason, stirred batch experiments of copper adsorption on chitosan immobilized onto glass beads were performed to estimate the surface diffusion coefficient and the chitosan film thickness, considering an inert solid glass core. The kinetic data were modelled by a surface diffusion model incorporating the external film mass transfer resistance. Column experiments were also performed for copper solution at different flow rates and a film-surface diffusion model was used to describe the breakthrough adsorption experiments, using the chitosan film thickness estimated from the batch experiment (ϕ = 2.5 µm). The input parameters for this model were determined by batch experiments or estimated from correlations available in the open literature. The surface diffusion coefficients (0.98-1.72 × 10−10 cm2 min−1) of copper in the chitosan film for different flow rates were estimated. The experimental data and the model agreed, indicating that the film thickness and the mass transfer parameters were well predicted. This article is protected by copyright. All rights reserved

Brazilian ginseng extracts are considered as functional ingredients to promote health benefits due to its bioactive properties. The present study aims at studying a two-step intensified extraction process that operates at ambient pressure in order to recover Brazilian ginseng roots bioactive compounds. The intensified process consists in a sequential extraction system using ethanol followed by water, envisioning the improvement of the overall extraction yield of the process to make it feasible. A technical-economic analysis of the proposed process was assessed through the use of computational simulation tools. The intensified process was compared to a simple extraction process using only ethanol or water as extracting solvents. The results showed that the lowest payback time for the investment is achieved not by minimizing process cost but at maximizing beta-ecdysone production. Economic performance indicators of income statement and profitability ratios showed that, even with higher investment cost, the intensified process presented higher economic attractiveness than the single step extraction processes using ethanol or water.

The effects of several operational parameters (pressure, temperature, CO2 flow rate, solution flow rate, injector type, and concentration of solute in the ethanol solution) during Supercritical AntiSolvent (SAS) precipitation process on the energy consumption cost per unit of manufactured product were investigated using experimental design technique. In this work, two different injectors were used. A completely randomized experiment would eventually require a modification of the apparatus after each experimental run. To avoid this, the experimental runs were done accordingly with a split-plot experimental design. For this study, Ibuprofen sodium salt was used as a model solute, ethanol was used as solvent, and CO2 was used as antisolvent. This supercritical fluid-based has been used successfully for several food and pharmaceutical applications since the production of small micro- and nanometer-sized particles have attracted growing interest in these industries. Focusing on energy saving, an SAS precipitation process was simulated using the SuperPro Designer simulation platform. The effect of temperature versus concentration of ethanolic solution and pressure versus solution flow rate interactions on the energy consumption cost per unit of manufactured product was demonstrated. The lowest estimated energy cost per unit of manufactured product was obtained using an ethanolic solution of 0.04 g mL−1 at 12 MPa of pressure and a solution flow rate of 1 mL min−1. This result was independent of the temperature. Thus, the present work reports a systematic energetic-economic study of the supercritical antisolvent micronization process, aiming increase knowledge about this process and its further incorporation by the food and pharmaceutical industries.

This work consists of the steps for the assembly of a Supercritical Antisolvent Precipitation laboratory equipment and evaluation of the parts acquisition costs. A flow diagram with all components was developed, a complete list of all necessary components was presented, and an estimate of the acquisition of these parts in Brazil was reported. The stages of construction along with the importance of each component in the equipment were discussed. An equipment designs were presented as a result of the current work that serve as a basis for consulting future work on the development of new equipment.

A supercritical particle formation equipment, designed and constructed by our research group, was validated in this study using supercritical CO2 as an antisolvent. Ibuprofen sodium salt was successfully micronized by supercritical antisolvent (SAS) precipitation. Ethanol and CO2 was used as solvent and antisolvent, respectively, and the effect of the operating conditions on the precipitation yield, residual organic solvent content and particle morphology were evaluated using a split-plot experimental design and the analysis of variance (ANOVA) method. This study showed that when selecting appropriate process conditions, it is possible to produce a sheet-like morphology, which is the best for tableting purposes, with high precipitation yield (70%) and low residual solvent content (4.7 mg kg−1).

Efficient encapsulation techniques and development of special delivery systems enhance the stability of target compounds, enabling their processing and application. Supercritical fluid extraction of emulsions (SFEE) is a promising alternative to process natural target compounds, due to its suitability to encapsulate poorly water-soluble compounds in an aqueous suspension, providing products with controlled particle size, stability and without toxicity. This chapter provides technological aspects and recent data (2016–2018) on the application of SFEE delivery systems to encapsulate compounds of great interest to the food and non-food industry.

High Turbulence Extraction Assisted by Ultrasound combined with Supercritical Antisolvent Fractionation (SAF) was done to intensify the recovery of bixin and phenolic compounds from semi-defatted annatto seeds. Annatto seeds are extensively used due to its colorant properties and bioactive potential in human health. Modifications were performed in the SAF experimental apparatus in order to prevent losses of product. Results show that supercritical fractionation resulted in particle yields between 72.2–80.5%, 20–50% phenolics, and 66% bixin.

Surfactants are widely used in the food industry to form and stabilize emulsion-based food and beverage products. The use of natural surfactant to replace the synthetic ones is a recent demand in industries. In this work, first it was evaluated the influence of hydrostatic pressure levels (up to 10 bars applying nitrogen), oily phase type and surfactant type. In addition, we propose a novel surfactant for the formulation of emulsions constituted of concentration of saponin-enriched extract. The extract containing saponins was obtained from pressurized hot water extraction of Brazilian Ginseng (Pfaffia glomerata) roots. The emulsions containing saponin extract were used for further processing by Supercritical Fluid Extraction of Emulsions (SFEE), using an oily bixin-rich extract from annatto seeds (Bixa orellana L.) as core material (extracting solution from hot ethyl acetate pressurized extraction). Since, the final product of SFEE achieved a low residual ethyl acetate concentration (9.4 ppm). Regarding droplet size similar results were obtained for the emulsion (549 nm) and the produced suspension (569 nm), which were 24.74% lower than the droplet size obtained in process not assisted with pressurized nitrogen atmosphere (730 nm). This work proposed the use of this alternative biosurfactant and the process that we named Ultrasound Emulsification Assisted by Nitrogen Hydrostatic Pressure (UEANHP), during the emulsification preparation step of the SFEE process.

Background: Cogeneration systems using biomass materials as woodships, agricultural and municipal solid waste, are well known and used in different places of the world. Today Brazilian sugarcane bagasse is an important energy source to these industries, most of them are self-sufficient in energy consumption and some generate energy surplus that is sold to the grid. There is a tendency forenlarging the electricity production at these industries and it is expected that in short to mid-term electricity produced from bagasse could become a product as important as ethanol or sugar. Methods: This study provides an overview of scientific papers and patents regarding the current situation of biomass cogeneration in Brazil and future prospects, focusing on the use of advanced cogeneration systems with integrated gasification combined andsupercritical steam cycles. Results: The results showed that much can still be done to improve the energetic efficiency at this sector. The current situation shows that although many companies are self-sufficient in terms of electricity just a few are able to sell electricity to the grid. There are many opportunities to better use the sugarcane bagasse and other biomass residues for energy production, from minor changes as improvements at the burning system to advanced power generation solutions. The minor changes can be accomplished with lower investment costs but with significant results for energy generation. Conclusion: The use of advanced power generation solutions as biomass gasification and supercritical steam cycles, proved to be highly efficient in energy production, generating a great electricity surplus.

The objective of this study was to investigate the technical-economic feasibility of supercritical antisolvent (SAS) technique for the precipitation of a vitamin complex containing riboflavin, δ-tocopherol and β-carotenein zein microcapsules. First, the following parameters were investigated for the precipitation of pure zein: pressure (7.0–16.0 MPa), anti-solvent flow rate (20–60 g/min), solution flow ratio (0.5–1.5 mL/min) and concentration of zein in an aqueous ethanol solution (0.02–0.04 g/mL). Then, at optimized SAS condition for zein precipitation (pressure of 16 MPa, temperature of 313 K, zein concentration of 0.02 mg/mL, solution flow rate of 1 mL/min and anti-solvent flow rate of 60 g/min) was performed the co-precipitation of the vitamins with zein. The results showed that the mean particle size of the microcapsules varied from 8 to 18 μm, depending on the vitamins encapsulated, being its morphology spherical, meanwhile the precipitation yield was within the range of 41–82 g/100 g.

The present study evaluates the use of supercritical fluid technology, particularly supercritical water gasification (SCWG), to add value to residues from a sugarcane biorefinery that produces first and second generation ethanol. This case study aims at elucidating how process system engineering tools such as thermal process integration, life cycle analysis, economic evaluation and multi-objective optimization can contribute to minimizing some future challenges of the industrial implementation of supercritical fluid- based technologies, which were discussed in the Workshop on Supercritical Fluids and Energy – SFE’13. In addition, this case study exposes future perspectives in terms of the requirements to further develop this field. The optimized solutions of the evaluated case showed that the SCWG process increases the overall efficiency of the process in terms of energy and carbon fixation. It decreases the CO2 equivalent emissions and it leads to a thermally self-sufficient process. The economic analysis showed a high investment cost but a feasibility of using the current market prices for the produced fuels and electricity.

The construction of a supercritical fluid extraction (SFE) plant inside or in close proximity to a sugarcane biorefinery producing first and second generation ethanol demonstrated to be very promising, increasing the economic potential of the SFE process in up to 57 %, since the SFE plant could use directly the ethanol, CO2, heat, and electricity already available, with lower prices. In this study, Brazilian ginseng roots were used as model bioactive compounds source and first the statistical influence of the extraction conditions including pressure (10–20 MPa), temperature (323–363 K), and CO2/ethanol proportion ratio (90:10, 50:50, and 0:100 %, w/w) on the β-ecdysone content in the extracts was experimentally evaluated and compared with literature results. SFE process evaluated experimentally at the present study showed higher selective extraction for β-ecdysone from Brazilian ginseng roots, providing an extract with up to 2.16 times higher β-ecdysone than the results obtained in previous studies. Thermal integration of the SFE process diminished energy requirements of the process, resulting in a reduction of cold utility requirement of 87 % and a final electricity demand of 7.5 kWh/g of β-ecdysone in the extract. In a situation in which the Brazilian ginseng roots price was increased to 4.71 USD/g, only the SFE integrated with the biorefinery solution would be economically feasible. Finally, the selling of the ginseng roots leftover could be an interesting answer to increase the economical attractiveness of the integrated SFE process to the biorefinery.

The formulation of clove essential oil as an emulsion using nonpurified aqueous extract from Pfaffia glomerata roots as surfactant has been experimentally demonstrated. Firstly, a commercial surfactant (OSA-modified starch) was used to evaluate the formulation of nano-emulsions in our devices. Results show that, the method of emulsification and its duration had an insignificant influence on all response variables. On the other hand, the influence of OSA-modified starch concentration was very significant (P

Anthocyanins are one of most important group of water-soluble and vacuolar pigments in nature. This phytochemical has attracted great interest to the food industry due to the wide range of biological activities including antioxidant and anti-inflammatory activities. However, the introduction of anthocyanins into food and/or medical fields has proved to be a major technological challenge since these compounds have low stability to environmental conditions during processing and storage. In this context, the present study evaluates the encapsulation of anthocyanin extract obtained from jabuticaba ( Myrciaria cauliflora ) skins in Polyethyleneglycol using supercritical CO 2 as solvent and ethanol as co-solvent. For comparison, a conventional method, ionic gelification, was employed to produce encapsulated particles by entrapment in Ca-alginate beads. The encapsulation efficiency of the extract in Ca-alginate beads was higher (98.67%) than those obtained by Rapid Expansion of Supercritical Solution (RESS) process (79.78%). Encapsulated particles made by RESS at different pressures, and temperatures, retained the extracts' biological activity. The best operating RESS process condition for anthocyanin extract encapsulation was determined as 313.15 K and 20 MPa. The degradation studies indicated that both encapsulated systems were more stable to light and temperature than the free extract. Ca-alginate encapsulated Anthocyanin extract release in acid buffer solution was incomplete and slower than when the extract was encapsulated by PEG. Both systems increased the stability of anthocyanin, although presenting different characteristics.

The effects of supercritical carbon dioxide (CO2) on waste banana peels for copper adsorption were evaluated. Supercritical CO2 was employed both in a solvent extraction for antioxidant compound recovery and in an emerging biomass treatment to increase the subsequent heavy metal-removal step; the latter is termed “explosion with supercritical CO2”. This lignocellulosic biomass was analyzed before and after being subjected to both processes by scanning electron microscopy and X-ray patterning. Thermal gravimetric and differential scanning calorimetry analyses were performed to understand the different effects of supercritical carbon dioxide employed in these two processes on banana peels. The explosion with supercritical CO2 process resulted in a more pronounced effect on the vegetable structure. Nevertheless, no increase in the copper-removal capacity was achieved. The adsorption studies showed similar behaviors for fresh and extracted samples, demonstrating that banana peels previously extracted with supercritical CO2 retained their adsorption capacity for subsequent heavy metal removal.

BACKGROUND: Green chemistry, also known as sustainable chemistry, refers to environmentally friendly chemicals and processes that result in reduced waste, elimination of costly end-of-the-pipe treatments; safer products, and reduced use of energy and resources. In this context this study aims to evaluate a novel green sensitizer support for photochemistry use. For this propose, Rose Bengal (RB) and juglone production were chosen as a model sensitizer and a model photoreaction, respectively. RESULTS: The results showed that the RB-alginate beads prepared using a solution of 20% CaCl2 had better stability in the solvent t-amyl alcohol.Comparing all the immobilized systems a larger reaction yield (57.5%)was obtained when the proportion of the beads in the photoreactor flaskwas 5% (v/v). Although when using suspended RB the reaction yield was better (62%) the environmental friendly attributes and economical advantages of immobilized systems overcome it. CONCLUSIONS: The potentiality of this new kind of sensitizer immobilization was demonstrated and a mechanism based on immobilization of cells was proposed. Furthermore the use of this novel green support presents a greater efficiency and potentially lower costs than the commercial supported RB Sensitox.

Commercial simulator Aspen Plus was used to simulate a biorefinery producing ethanol from sugarcane juice and second generation ethanol production using bagasse fine fraction composed of parenchyma cells (P-fraction). Liquid hot water and steam explosion pretreatment technologies were evaluated. The processes were thermal and water integrated and compared to a biorefinery producing ethanol from juice and sugarcane bagasse. The results indicated that after thermal and water integration, the evaluated processes were self-sufficient in energy demand, being able to sell the surplus electricity to the grid, and presented water intake inside the environmental limit for São Paulo State, Brazil. The processes that evaluated the use of the bagasse fine fraction presented higher economic results compared with the use of the entire bagasse. Even though, due to the high enzyme costs, the payback calculated for the biorefineries were higher than 8 years for all cases that considered second generation ethanol and the net present value for the investment was negative. The reduction on the enzyme load, in a way that the conversion rates could be maintained, is the limiting factor to make second generation ethanol competitive with the most immediate uses of bagasse: fuel for the cogeneration system to surplus electricity production.

Producción Científica, Recently, supercritical fluid extraction (SFE) has been indicated to be utilized as part of a biorefinery, rather than as a stand-alone technology, since besides extracting added value compounds selectively it has been shown to have a positive effect on the downstream processing of biomass. To this extent, this work evaluates economically the encouraging experimental results regarding the use of SFE during annatto seeds valorization. Additionally, other features were discussed such as the benefits of enhancing the bioactive compounds concentration through physical processes and of integrating the proposed annatto seeds biorefinery to a hypothetical sugarcane biorefinery, which produces its essential inputs, e.g., CO2, ethanol, heat and electricity. For this, first, different configurations were modeled and simulated using the commercial simulator Aspen Plus® to determine the mass and energy balances. Next, each configuration was economically assessed using MATLAB. SFE proved to be decisive to the economic feasibility of the proposed annatto seeds-sugarcane biorefinery concept. SFE pretreatment associated with sequential fine particles separation process enabled higher bixin-rich extract production using low-pressure solvent extraction method employing ethanol, meanwhile tocotrienols-rich extract is obtained as a first product. Nevertheless, the economic evaluation showed that increasing tocotrienols-rich extract production has a more pronounced positive impact on the economic viability of the concept., Fundação de Amparo à Pesquisa do Estado de São Paulo (Brasil) -FAPESP (processes 2013/18114-2; 2015/06954-1), Ministério da Educação (Brasil) - CAPES (process 7545-15-0), Conselho Nacional de Desenvolvimento Científico e Tecnológico (Brasil) - CNPq ( grant 301301/2010-7), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) y Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP) - (Brasil) - (Procesos 2012/10685-8; 2015/13299-0)

Glycerol is an important by-product of biodiesel production. It is used in many industrial segments, but the increasing production of this chemical has become an issue of concern. Many studies have been done to give new applicability to this product; a promising field is the usage of glycerol for energy production. Therefore, this study evaluates the technical and economic feasibility of a new and potential proposal at the national level, the generation of electricity and heat, through a cogeneration system using glycerol. The results demonstrate the viability of this proposal, since the payback on capital invested obtained was approximately 4 years, with the possibility of reduction to 3 years when installed in regions with low infrastructure.

This study provides a preliminary contribution to the development of an industrial process for the UV/TiO2 water treatment by introducing a novel support for TiO2 immobilization. For the following study, Methylene Blue (MB) was chosen as the model dye to evaluate this novel immobilization system. The results showed that TiO2 immobilized in a Ca–alginate bead retained its photoactivity during all of the experiments and the TiO2-gel beads presented good stability in water for maintaining its shape after several uses. When a proportion of 10% (v/v) of these beads was used, the configuration system demonstrated an improved mass transfer and consequently enhanced degradation efficiency. Experiments were also performed using ‘recycled’ beads. The results showed an increase in the degradation efficiency when the beads were reused, with an eventual ‘self-destructive’ effect. These studies showed great promise regarding the recyclable reagents with a reduction in waste at no greater cost or reduction in efficiency. Therefore, the potential of TiO2-gel beads as a simple and environmentally friendly catalyst for continuous use was developed.

In the present study, the software Aspen Plus® was used to analyse two different systems for CO2 recycle in a SFE process for extraction of more polar compounds using ethanol as co-solvent, the most common co-solvent used due to its environment-friendly nature. The extraction process of β-ecdysone from Brazilian ginseng roots was considered as example in the computational simulations. The first CO2 recycle system, named Recycle A, considered the compression of the CO2 separated in the second flash to the recycle pressure assumed at the first flash tank, its cooling to 25 °C and recirculation, while the second recycle system, named Recycle B, considered the cooling and pumping of the CO2 separated in the second flash, its heating to 25 °C and recirculation. The best techno-economic condition to operate the recycling step would be using Recycle A at 40 bar and 30 °C considering a stand-alone SFE process; and using Recycle B at 40 bar and 40 °C, considering this process in close proximity of a hypothetical sugarcane biorefinery. Therefore, these results suggest that the selection where would be located the SFE plant should be taken into account during the first steps of the process design.