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Item type: Item , A critical review of holistic 4E approaches for assessing sustainable aviation fuel pathways: implications for feedstock, technology, policy and scale-up(2026) Gonzales, Thiago da Silva; Lamas, Giulia Cruz; Silva, Simone Monteiro e; Ferreira, Ana Filipa; Silveira, Edgar AmaralThe aviation sector urgently requires decarbonization, positioning Sustainable Aviation Fuels (SAF) as the most viable near-term option for reducing fossil jet fuel dependence. However, SAF scale-up remains constrained by coupled technological, thermodynamic, economic, environmental, and policy related trade offs. Although many studies assess individual dimensions of SAF production, the literature still lacks a critical synthesis explicitly connecting Energy, Exergy, Economic, and Environmental (4E) evidence across certified pathways. This review examines 4E related approaches applied to SAF by linking energy and exergy analyses with techno economic assessment, life cycle assessment (LCA), and their exergoeconomic and exergoenvironmental extensions where available. The systematic review reveals a fragmented evidence base, with only a limited subset of studies quantitatively addressing all four dimensions. Hydroprocessed Esters and Fatty Acids remains the most mature and economically competitive route, but its scalability is limited by sustainable lipid feedstock availability, hydrogen sourcing, and land use constraints. Gas-to-Jet, Alcohol-to-Jet, and Sugar-to-Jet offer greater feedstock flexibility or biochemical innovation, but face higher capital intensity, upgrading complexity, hydrogen demand, or blend limit restrictions. Across pathways, thermodynamic irreversibilities in heat exchange, separation, syngas conditioning, fermentation, and upgrading stages propagate into cost formation and environmental burdens. LCA evidence shows that Greenhouse gases reductions depend strongly on feedstock origin, hydrogen source, allocation choices, and system boundaries. By organizing these interdependencies through a pathway level 4E indicator linking matrix, this review provides an evidence based foundation for more transparent comparative assessments, process optimization, investment analysis, and policy design for SAF deploymentItem type: Item , Techno-economic and CO2 net assessment of dimethyl carbonate production from biomass-derived methano(2025) Custodio, Renan Fagundes; Valarini Junior, Osvaldo; Vieira, Admilson Lopes; Souza, Thiago Leandro de; Bezerra, Felipi Luiz de Assunção; Rocha, Lucas BonfimThe increasing concern over greenhouse gas emissions, particularly CO2, has emphasized the urgency for practical solutions to mitigate the environmental impacts of climate change. This study assessed the technical, economic, and environmental feasibility of producing dimethyl carbonate (DMC) through an integrated route using methanol derived from biomass gasification in sugarcane-based industries. Unlike previous studies that analyzed isolated aspects of DMC production, this research was conducted through process modeling and simulation in Aspen Plus® V12.1, evaluating key performance indicators such as conversion rates, product purity, capital and operating expenses, and CO2 emissions. A DMC conversion rate of 78.06% and a purity level of 96.80% were achieved. However, the integration of methanol production increased both CAPEX and OPEX, leading to a net present value (NPV) of R$ 36.7 million over 10 years, lower than alternative routes using commercially available methanol. Additionally, the process resulted in a net CO2 emission of 3.41 kg CO2 per kg of DMC, exceeding conventional methods. These findings suggest that under the evaluated conditions, process integration did not offer economic advantages, despite many environmental advantages over commercially available methanol.Item type: Item , Core–shell structured PtCu/C applied in a high-temperature direct ethanol electroreformer to produce green H2 at reduced energy demand with high CO2 selectivity: performance and techno-economic analyses(2026) Paula, Dryade Ferreira de; Crisafulli, Rudy; González Cobos, Jesús; Caravaca, Angel; Linares León, José JoaquínThree different electrocatalysts have been prepared, characterized, and applied to a high-temperature direct ethanol polymer electrolyte membrane electroreformer (DEPEME) based on the removal of surface Cu from the initial PtxCu/C (x = 3, 1, and 1/3) raw materials. The resulting structure consisted of a Pt-enriched shell on a PtCu alloy core deposited on C [alloyed PtxCu@PtyCu/C (y c x)], achieved after the acid treatment of the prepared catalysts, in a core–shell (CS) configuration. This structure is confirmed by X-ray diffraction, which evidences the formation of a PtCu alloy, whereas X-ray photoelectronspectroscopy reveals an enriched Pt shell. Finally, transmission electron microscopy images revealed the dispersed deposition of metal nanoparticles at the nanoscale range. Regarding the electrochemical performance, the CS materials displayed enhanced CO tolerance and ethanol electro-oxidation (EEO) performance, characterized by increased current density and a lower onset potential compared to Pt/C. These results were corroborated at the high-temperature DEPEME condition of 150 1C. Moreover, the monitoring of the EEO products revealed that the CS PtCu materials notably enhanced the selectivity for CO2, resulting in a desirable combination of high hydrogen production rate (0.205 kg of H2 m2 h1) and CO2 selectivity (close to 50%) at a reduced energy consumption (25.46 kWh kg H21). Finally, a techno-economic analysis presents the potential of using ethanol produced in a sugarcane plant from bagasse (second-generation) and estimates the cost of H2 produced compared to that of a PEM water electrolyzer.Item type: Item , Simulation and thermodynamic evaluation of woody biomass waste torrefaction(2025) Gonzales, Thiago da Silva; Silva, Simone Monteiro e; Lamas, Giulia Cruz; Rodrigues, Pedro Paulo de Oliveira; Siqueira, Mario Benjamim Baptista de; Follegatti Romero, Luis Alberto; Silveira, Edgar AmaralTorrefaction is a thermochemical pretreatment that enhances biomass properties, improving energy density, decomposition resistance, and hydrophobicity, making it a viable alternative as biofuel. This study performed a thermodynamic assessment of the torrefaction process for urban forest waste, integrating experimental data with two-step reaction kinetic modeling to evaluate the torrefaction product yields and properties using Aspen Plus software. The process was modeled with a yield reactor, employing the Peng−Robinson equation to describe vapor-phase behavior and empirical correlations to predict solid-phase properties. Simulations were validated against experimental data for temperatures between 225 and 275 °C, achieving an absolute deviation of less than 5%. Energy consumption ranged from 368 kJ·h−1 for light torrefaction to 1853 kJ·h−1 for severe torrefaction. Process irreversibility varied from 326 kJ·h−1 (3% exergy destruction) in light torrefaction to 3993 kJ·h−1 (16% exergy destruction) in severe torrefaction. The research provides a robust model for torrefaction scale-up that is adaptable to diverse biomass feedstocks and process conditions, highlighting its potential for optimizing energy use and improving sustainability in biomass utilization.Item type: Item , Statistical and multivariate evaluation of olive oil degradation during long-term storage(2025) Almeida, Erislene Silva de; Silva, Danyel Ferreira da; Oliveira, Natália Soares de; Fernandes, Juliana S.; Oliveira, Bruna Cecília de Sousa; Silva, Simone Monteiro e; Almeida, Fernanda Vasconcelos de; Braga, Jez Willian Batista; Dias, Ana Cristi BasileExtra virgin olive oil (EVOO) is valued for its flavor and health benefits. However, its quality can decline during storage, reducing food quality and the effectiveness of therapeutic compounds when used as a pharmaceutical excipient. While the oxidative stability of extra virgin olive oil has been widely studied for food quality and shelf life, its crucial role as a pharmaceutical excipient and the impact of long-term degradation on the effectiveness and stability of active compounds remain largely unexplored. This study examined 14 commercial EVOO samples immediately after opening and after three years of storage. Standard methods were used to measure the peroxide value, p-anisidine value, acidity, antioxidant activity, and extinction coefficients. The data were analyzed with statistical and chemometric tools. Initially, all oils met international quality standards. After three years, most samples showed significant deterioration, especially a decline in antioxidant activity and an increase in K232 values. Statistical tests confirmed differences among samples, and pairwise comparisons indicated significant differences consistent with degradation between T0 and T1. Principal component analysis (PCA) identified three main patterns related to oxidation and antioxidant capacity, and clustering distinguished between stable and unstable samples. Overall, the stability of the studied EVOOs varied by brand, influenced by their natural composition and storage conditions. Multivariate analysis confirmed that antioxidant activity and extinction coefficients are key indicators of oxidative degradation. This finding highlights multivariate analysis as a valuable approach for monitoring the oxidative stability of oils and ensuring EVOO quality for both food and pharmaceutical application.