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Influence of environmental factors on α-tocopherol levels in Moringa oleifera e...
Kessler, Júlia C.; Manrique, Yaidelin A.; Martins, Isabel M.; Ribeiro, António E.; Rodrigues, Alírio; Barreiro, Filomena; Dias, Madalena M.Moringa oleifera L. extracts (Mo) have attracted attention as a sustainable and effective alternative to synthetic ingredients for cosmetic formulations. The unique and diverse phytochemical profile of the Mo tree enhances the quality and appeal of commercial products, as evidenced by numerous studies and patents. Supercritical carbon dioxide extraction (SFE-CO2) is particularly advantageous for this purpose, o...
Cork waste-based adsorbents for glycerol removal from biodiesel: a sustainable ...
Garção, Maria Isabella Lima; Milani, Eduardo C.; Camilo, Gabriel L.; Díaz de Tuesta, Jose Luis; Gomes, Maria Carolina Sérgi; Ribeiro, António E.This work aims to use activated carbon from industrial cork waste as a novel method for glycerol removal from crude biodiesel produced using waste cooking oil, combining two residues to obtain both high-quality biodiesel and highly adsorbent activated carbon. The study first optimizes the biodiesel production conditions, achieving the highest ester yield at 30 degrees C, with a 1:9 oil-to-ethanol molar ratio, 1...
Removal of metformin from aquatic matrices using cork-based adsorbents
Morizaki, Gabrielle Tokawa; Gomes, Maria Carolina Sérgi; Queiroz, Ana; Brito, Paulo; Ribeiro, António E.Anthropogenic activities associated with industrial development, urbanization, and population growth have significantly contributed to the presence of various pollutants in aquatic environments. Among these contaminants, emerging micropollutants have raised considerable concern. The detection and quantification of these substances require advanced analytical techniques due to their occurrence at extremely low c...
Dry purification of ethanolic biodiesel through adsorption using almond shell b...
Mezzalira, Melissa Giacomet; Gomes, Maria Carolina Sérgi; Queiroz, Ana; Ribeiro, António E.; Brito, PauloPetroleum-based fuels and non-renewable sources remain dominant in the global energy supply, meeting 80% of global energy demand in 2023. However, using these non-renewable fuels results in significant emissions of pollutants into the atmosphere, including greenhouse gases such as carbon dioxide (CO2). In this context, biodiesel is a potential alternative to meet global energy demand as a substitute for non- re...
Biodiesel production by transesterification using choline hydroxide as catalyst
Brito, Paulo; Lima, Renata; Queiroz, Ana; Ribeiro, António E.Biodiesel is a mixture of fatty acid methyl esters (FAMEs) and is a biodegradable and renewable fuel, produced from fat sources mainly composed of triglycerides. The use of ionic liquids (ILs) in biodiesel catalytic production has been studied mainly in the ecological field, as it allows a high recycling efficiency. Choline (2-hydroxyethyl trimethylammonium)-based ILs have received attention due to their biocom...
Purificação a seco do biodiesel etanólico através de adsorção utilizando materi...
Mezzalira, Melissa Giacomet; Gomes, Maria Carolina Sérgi; Queiroz, Ana; Brito, Paulo; Ribeiro, António E.O crescente interesse por fontes de energia sustentáveis tem impulsionado a busca por alternativas aos combustíveis fósseis. Nesse contexto, o biodiesel surge como uma possível alternativa ao diesel, devido às suas propriedades compatíveis.1 Esse biocombustível pode ser obtido a partir de diversas matérias-primas, incluindo o óleo alimentar usado (OAU), promovendo o reaproveitamento eficiente de resíduos.2 A pu...
Remoção de estrogénios por adsorção: Produção de adsorventes a partir de resídu...
Exposto, Bruno Marques; Queiroz, Ana; Ribeiro, António E.; Brito, PauloOs poluentes emergentes são uma preocupação ambiental crescente no setor industrial. Estes compostos são detetados em concentrações cada vez superiores na natureza devido à sua persistência.1 Muitos poluentes emergentes são também considerados micropoluentes devido à sua perigosidade mesmo em concentrações muito baixas.
Preparation and characterization of adsorbents from waste biomass for estrogen ...
Exposto, Bruno Marques; Queiroz, Ana; Ribeiro, António E.; Brito, PauloThe environmental impact associated with socioeconomic development is currently a major challenge [1]. One concern relates to inadequate waste disposal of micropollutants, such as endocrine disruptors, which consist of substances with harmful effects even in very low concentrations (µg/L or ng/L) [2], namely natural estrogenic hormones E1, E2 and E3, and synthetic estrogenic hormone EE2, which chemical structures.
Valorização de resíduos de biomassa para a remoção de estrogénios em matrizes a...
Exposto, Bruno Marques; Queiroz, Ana; Ribeiro, António E.; Brito, PauloOs estrogénios são substâncias consideradas disruptores endócrinos, ou seja, têm a capacidade de desregular o sistema endócrino dos seres vivos. Estes compostos podem ocorrer naturalmente, como a estrona (E1) e o estradiol (E2), ou na forma sintetizada, como o etinilestradiol (EE2) [1]. Os efeitos nocivos destes fármacos manifestam-se mesmo em baixas concentrações (µg/L ou ng/L), sendo considerados como micropo...
Valorisation of waste cooking oils through [HMIM][HSO4] ionic liquid-catalysed ...
Brito, Paulo; Diniz, Heloísa Oliveira Resende; Queiroz, Ana; Ribeiro, António E.Biodiesel consists of a mixture of fatty acid methyl esters (FAMEs) and is produced by processing vegetable oils or animal fats. Oil sources, not competing with the food market, such as waste cooking oils (WCOs), can be used, and ionic liquids (ILs) are promising catalysts, since they promote esterification/transesterification reactions to biodiesel. The objective was to study biodiesel production using 1-methy...