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Funding Information: Thanks are also due to FCT for the project PTDC/BII-BIO/30884/2017. A.F.P. and M.M.M. thank FCT for funding through the Individual Call to Scientific Employment Stimulus (ref. 2020.01614.CEECIND/CP1596/CT0007 and CEEC-IND/02702/2017, respectively). O.D. is thankful for the Ph.D. grant supported by FCT (2021.05322.BD). Funding Information: This work was funded by Portuguese funds through Fundação para a Ciência e a Tecnologia (FCT/MCTES) in the framework of the projects UIDB/50006/2020, UIDP/50006/2020, and EXPL/BII-BIO/0436/2021 and also by BIP Proof 2022/2023 through UI-Transfer, a cofunding project by European Union through COMPETE 2020-Portugal 2020, CIQUP, Centro de Investigação em Química da Universidade do Porto (UIDB/00081/2020), and IMS, Institute of Molecular Sciences (LA/P/0056/2020). Publisher Copyright: © 2023 The Authors. Published by American Chemical Society. The control of the oxidative stability of biodiesel and blends of biodiesel with diesel is one of the major concerns of the biofuel industry. The oxidative degradation of biodiesel can be accelerated by several factors, and this is most critical in the so-called second generation biodiesel, which is produced from low-cost raw materials with lower environmental impacts. The addition of antioxidants is imperative to ensure the oxidative stability of biodiesel, and these are considered products of high commercial value. The antioxidants currently available on the market are from synthetic origin, so the existence/availability of alternative antioxidants of natural origin (less dependent on fossil sources) at a competitive price presents itself as a strong business opportunity. This work describes and characterizes a sustainable alternative to synthetic antioxidants used in the biodiesel market developed from extracts of vineyard pruning waste (VPW), which are naturally rich in phenolic compounds with antioxidant properties. A hydrothermal extraction process was applied as a more efficient and sustainable technology than the conventional one with the potential of the extracts as antioxidant additives in biodiesel evaluated in Rancitech equipment. The VPW extract showed comparable antioxidant activity as the commercial antioxidant butylated hydroxytoluene (BHT) typically used in biodiesel. The stability of the biodiesel is dependent from the amount of the extract added. Further, for the first time, the assessment of the environmental impacts of using natural extracts to control the oxidative stability of biodiesel in the production process is also discussed as a key factor of the process environmental sustainability. publishersversion published

24 compostos farmacêuticos foram detetados no efluente de uma estação portuguesa de tratamento de águas residuais (ETAR A) utilizada como caso de estudo. Dos 24 fármacos detetados apenas 9 apresentam um nível de risco ambiental baixo para os organismos representativos dos três níveis tróficos considerados (Algas, Daphnia magna e Peixes), de acordo com as diretrizes da Comissão Europeia, enquanto a atorvastatina, a cafeina, a carbamazepina e a venlafaxina apresentam um nível de risco ambiental alto, os restantes são caracterizados por um risco ambiental médio. Efeitos adversos são expectáveis nos ecossistemas aquáticos e na saúde humana devido à presença destes compostos. Na ausência de uma legislação nacional específica, com o objetivo de garantir que todos os fármacos apresentem um nível de risco ambiental baixo no efluente final, foi sugerida a hipótese de implementação de unidades terciárias de tratamento de plasma não térmico (PNT) e de ozonização (OZ) na ETAR A. As unidades de PNT e de OZ foram projetadas para tratar 10% do efluente total da ETAR A com o objetivo de reutilizar esta água para a rega. Calculou-se, com base em dados operacionais e extrapolados pela literatura, a energia elétrica necessária para operar cada uma destas tecnologias, obtendo-se um consumo de 0,40 kWh/m3 para o OZ e de 2,38 kWh/m3 para o PNT. A comparação dos tratamentos terciários de PNT e OZ foi desenvolvida com o intuito de calcular os impactes ambientais resultantes da implementação de cada uma destas tecnologias com base numa análise de ciclo de vida (ACV) com o objetivo de avaliar qual a alternativa mais sustentável de um ponto de vista ambiental. Neste estudo foram incluídas todas as etapas de tratamento praticadas na ETAR A, tanto em relação à fase líquida, como à fase sólida e à gasosa. A ACV foi desenvolvida utilizando o software OpenLCA 1.10.3 equipado com a base de dados Ecoinvent 3.5. Os métodos utilizados para a estimativa dos impactes ambientais foram o ReCiPe 2016 Endpoint (H) e USEtox (provisório + recomendado). Concluiu-se que a tecnologia que é ambientalmente mais sustentável é a tecnologia de OZ, sendo que é caracterizada, em média, por um aumento significativamente menor dos impactes ambientais associados à sua operacionalização, em comparação com a tecnologia de PNT, em cada um dos indicadores estudados (métodos ReCiPe 2016 Endpoint (H) e USEtox (provisório + recomendado)). Para minimizar os impactes ambientais associados, a escolha da reutilização da água residual tem que ser avaliada caso a caso, em função do corpo recetor que recebe a descarga e dos recursos hídricos disponíveis na área de estudo 24 pharmaceutical compounds were detected in the effluent of a Portuguese wastewater treatment plant (WWTP A) used as case study. From the 24 detected pharmaceuticals, only 9 of them are characterized by low environmental risk for the representative organisms of the three trophic levels considered (Algae, Daphnia magna and Fish) according to the European Commission Directive, while atorvastatin, caffeine, carbamazepine and venlafaxine are characterized by high environmental risk. The rest of the compounds are characterized by a medium environmental risk. Adverse effects can be expected on aquatic ecosystems and human health due to the presence of these compounds. In the absence of a specific national legislation, in order to guarantee that all the pharmaceuticals provide low environmental risk, it was hypothesized the implementation of tertiary non-thermal plasma treatment unit (NTP) and ozonation unit (OZ) in the WWTP A. The NTP and OZ units were designed to treat 10% of the total effluent of WWTP with the purpose of reusing this water for irrigation. Based on operational data and data extrapolated from literature, the electric energy necessary for each of these technologies was calculated, obtaining a consumption of 0,40 kWh/m3 for the OZ and 2,38 kWh/m3 for the NTP. The comparison of the tertiary treatments of NTP and OZ was developed in order to calculate the environmental impacts resulting from the implementation of each of these technologies based on a Life Cycle Assessment (LCA) with the goal of assessing which one is the most sustainable from an environmental point of view. In this study, all treatment steps, liquid, solid and gaseous phase, practiced at the WWTP in question were included. The LCA was developed using OpenLCA 1.10.3 software equipped with Ecoinvent 3.5 database, and the methods used to estimate the environmental impacts were ReCiPe 2016 Endpoint (H) and USEtox (recommended + interim). It was concluded that the technology that is environmentally more sustainable is the OZ unit, and it is characterized by a significant lower increase in environmental impacts associated with its implementation, compared to the increase associated with the implementation of the NTP unit, in each of the indicators studied (ReCiPe 2016 Endpoint (H) and USEtox (recommended + interim) methods). To minimize the associated environmental impacts, the choice of reusing treated wastewater has to be evaluated on a case-by-case basis, depending on the receptor water body and on the water resources available in the studied area.