The objective of this study was to investigate the influence of temperature and pressure on the extraction of Baru almond oil using pressurized CO₂. From the obtained data, it was found that variations in pressure and temperature influenced the oil yield and total amount of phytosterols. The maximum yield of Baru oil achieved was approximately 30%, obtained at a pressure of 28 MPa and 60 °C. The phytosterols identified were campesterol, stigmasterol, and β-sitosterol, with a maximum content of 169.5 ± 4.2 mg/100 g of oil obtained at 20 MPa and 60 °C. Among these, β-sitosterol was the most abundant, accounting for 60% of the total phytosterol content under all the experimental conditions. The flavonoid content in the extracts was also quantified, with the total flavonoid levels ranging between 255 and 275 mg/100 g of oil depending on the experimental conditions. The fatty acid profile of the extracted oil predominantly consisted of oleic (51%) and linoleic (28%) acids.

Due to the need to create new technologies for the production of biofuels, there are techniques to perform oil extraction from oilseeds, such as the supercritical extraction method using CO2, where the seed used to carry out the study (peanut) is subjected to CO2 at high pressures and temperatures, thus becoming a supercritical fluid and carrying out the process of extracting the oil from the seed to produce biodiesel more efficiently. There is another extraction technique in which organic solvents are used. Still, this method has some difficulties that end up causing damage to the environment as it is a process that consumes a significant amount of time and energy. Peanut is the world's fourth-most cultivated oilseed, with large plantations in the Americas, Africa, and Asia. Its planting is carried out to produce grains, oil, and bran. CO2 has interesting physicochemical properties since it is an inert, non-polar, non-flammable, odorless, tasteless gas and has critical parameters and low value. It has a critical pressure of 72.01 bar and a critical temperature of 31.1 °C. The present work presents data from a kinetic study of the supercritical extraction of peanut oil under pressure and temperature conditions of 200 bar, 280 bar, 40 °C, and 60 °C. This project uses an experimental matrix to help carry out the experiments. At the end of the experiments, we obtained a yield of 30% in the supercritical method (80 min) and a percentage yield of 26% by Soxhlet using ethanol as a solvent for 480 minutes.

This study evaluated the extraction of oils from the seeds of bacupari (Garcinia brasiliensis Mart.) and leiteira (Tabernaemontana catharinensis), using carbon dioxide (CO₂) in the supercritical state. The effects of temperature (40, 50, and 60 °C) and pressure (20, 24, and 28 MPa) on the yield and extraction kinetics were investigated. The results indicated that, within the studied limits, temperature had a negligible influence on the process, while pressure had a greater impact on the yields owing to its effect on the density of supercritical CO₂ and the solubility of the extracted compounds. The maximum yields obtained were 14.8% for bacupari and 15.2% for leiteira, with most of the oil extracted within the first 30 min, indicating initial rapid extraction. Chemical composition analysis revealed relevant bioactive compounds in bacupari, including oleic acid (35%) and delta-tocopherol (19.6%). In leiteira, the main compounds identified were hexanedioic acid (29.2%) and stigmast-5-ene (7.95%). These results suggest the potential application of these oils in the pharmaceutical, cosmetic, and food sectors, while also highlighting the feasibility of using supercritical CO₂ as an extraction method for these plant matrices.

O interesse em utilizar a biomassa para produção de energia tem crescido consideravelmente. Além do reaproveitamento de resíduos de indústrias agrícolas e alimentícias a energia da biomassa evita o aumento de dióxido de carbono na atmosfera. A biomassa residual pode ser utilizada de diversas maneiras com o objetivo de gerar energia. Uma delas, e talvez a mais eficiente, é a produção de hidrogênio. O estudo da produção de hidrogênio por fontes alternativas cresceu nos últimos anos em função da necessidade da utilização de fontes renováveis e do desenvolvimento tecnológico de células a combustível. Dentre várias alternativas, a gaseificação em água supercrítica tem a vantagem de não ser específica para determinado resíduo (agrícolas ou de efluentes de processos diversos). Durante a gaseificação em água supercrítica, ou seja, em temperaturas e pressões maiores ou iguais a 374 °C e 22.1 MPa, respectivamente, são produzidos em grande parte hidrogênio (H2) e dióxido de carbono (CO2). No entanto, por atingir temperaturas e pressões elevadas, os materiais para construção e manutenção da planta de produção merecem atenção especial e o alto custo operacional torna-se o maior obstáculo para o desenvolvimento desta tecnologia. Contudo, verifica-se que, além de grande eficiência energética, a utilização de hidrogênio em células a combustível gera apenas água como subproduto, tornando, portanto, a substituição de processos que utilizam combustíveis fósseis por processos que utilizem fontes alternativas, conveniente e oportuna. A tecnologia de geração de hidrogênio em água supercrítica atende a esse anseio e novos estudos vêm sendo realizados para torná-la mais viável.

This study aimed to investigate the liquid–liquid equilibrium (LLE) behavior of sesame fatty acid ethyl ester (FAEE) and methyl ester (FAME) in combination with glycerol and the co-solvents ethanol and methanol. FAEE and FAME were produced through the transesterification of mechanically extracted and purified sesame oil, using potassium hydroxide (KOH) as a homogeneous base catalyst. The reactions were conducted in ethanol and methanol to produce FAEE and FAME, respectively. Post-reaction, the products were separated and purified, followed by an analysis of the LLE behavior at 313.15 K and 323.15 K under atmospheric pressure (101.3 kPa). The experimental process for the miscibility analysis utilized a jacketed glass cell adapted for this study. Miscibility limits or binodal curves were determined using the turbidity-point method. Tie lines were constructed by preparing mixtures of known concentrations within the two-phase region, which allowed the phases to separate after agitation. Samples from both phases were analyzed to determine their composition. This study revealed that higher temperatures promoted greater phase separation and enhanced the biodiesel purification process. The NRTL model effectively correlated the activity coefficients with the experimental data, showing good agreement, with a root-mean-square deviation of 3.5%. Additionally, the data quality was validated using Marcilla’s method, which yielded an R² value close to 1. Attraction factors and distribution coefficients were also calculated to evaluate the efficiency of the co-solvents as extraction agents. The findings indicated higher selectivity for methanol than for ethanol, with varying degrees of distribution among the co-solvents. These results offer significant insights into enhancing biodiesel production processes by considering the effects of co-solvents on the LLE properties of mixtures, ultimately contributing to more efficient and cost-effective biodiesel production.

A presente pesquisa buscou-se investigar, quantificar o rendimento obtido do conteúdo lipídico obtidos a partir do sansão do campo utilizando CO₂ pressurizado em condição supercrítica gerando uma curva cinética de extração, para avaliar os efeitos das variáveis do processo (variáveis termodinâmicas), e comparar com a proporção de extração obtida utilizando o procedimento tradicional (procedimento com solventes orgânicos tradicionais). O sansão do campo é conhecido por seu potencial terapêutico multifuncional, atuando em processos anti-inflamatórios e antimicrobianos, bem como seu uso no tratamento de condições como bronquite e câncer de mama. Foram utilizados dois métodos de extração de óleo para se obter o conteúdo lipídico presente na amostra. Foi utilizado solvente orgânico (álcool etílico) e dióxido de carbono na condição supercrítica para realizar a extração de óleo do sansão do campo. O álcool etílico gerou um aproveitamento de 2% após 8 horas de extração, enquanto o dióxido de carbono na condição supercrítica obteve um rendimento de 4% em apenas 80 minutos. O processo de extração empregando fluido supercrítico de CO₂ se destacou-se devido à sua eficiência acentuada em relação a duração do processo. A análise quantitativa baseada em estatística experimental demonstrou que a variação de variáveis termodinâmicas (pressão e temperatura) não demonstrou significância estatística considerável o rendimento da extração com dióxido de carbono na condição supercrítica. Estudos prévios demonstram que a extração com líquidos pressurizados também pode ser eficaz para diferentes matrizes oleaginosas, a utilização de métodos estatísticos é essencial para validar experimentalmente os rendimentos em processos de extração.