• Energy Research
• 7. Clean energy close
• 11. Sustainability close
• EU close

AbstractPyrochemical methods for reprocessing of spent nuclear fuel are under development as an alternative to the hydrometallurgical processes. The pyrochemical reprocessing process developed in ITU is based on electrorefining of spent fuel in molten LiCl-KCl salt using solid aluminium cathodes. This is followed by a chlorination process for the recovery of actinides from the actinide-aluminium alloys formed and exhaustive electrolysis is proposed for clean-up of the salt from the remaining actinides. In this paper, all investigated techniques are described and the main achievements are summarised. The emphasis is given to the electrorefining, which represents the core process for homogeneous recovery of all actinides from the spent fuel. High efficiency of the process and excellent recovery of actinides over lanthanides have been achieved and very high capacity of solid aluminium to take up actinides has been demonstrated.

This work (and the companion paper, Part II) presents new experimental data for the combustion of n-C3–C6 alcohols (n-propanol, n-butanol, n-pentanol, n-hexanol) and a lumped kinetic model to describe their pyrolysis and oxidation. The kinetic subsets for alcohol pyrolysis and oxidation from the CRECK kinetic model have been systematically updated to describe the pyrolysis and high- and low-temperature oxidation of this series of fuels. Using the reaction class approach, the reference kinetic parameters have been determined based on experimental, theoretical, and kinetic modeling studies previously reported in the literature, providing a consistent set of rate rules that allow easy extension and good predictive capability. The modeling approach is based on the assumption of an alkane-like and alcohol-specific moiety for the alcohol fuel molecules. A thorough review and discussion of the information available in the literature supports the selection of the kinetic parameters that are then applied to the n-C3–C6 alcohol series and extended for further proof to describe n-octanol oxidation. Because of space limitations, the large amount of information, and the comprehensive character of this study, the manuscript has been divided into two parts. Part I describes the kinetic model as well as the lumping techniques and provides a synoptic synthesis of its wide range validation made possible also by newly obtained experimental data. These include speciation measurements performed in a jet-stirred reactor (p = 107 kPa, T = 550–1100 K, φ = 0.5, 1.0, 2.0) for n-butanol, n-pentanol, and n-hexanol and ignition delay times of ethanol, n-propanol, n-butanol, n-pentanol/air mixtures measured in a rapid compression machine at φ = 1.0, p = 10 and 30 bar, and T = 704–935 K. These data are presented and discussed in detail in Part II, together with detailed comparisons with model predictions and a deep kinetic discussion. This work provides new experimental targets that are useful for kinetic model development and validation (Part II), as well as an extensively validated kinetic model (Part I), which also contains subsets of other reference components for real fuels, thus allowing the assessment of combustion properties of new sustainable fuels and fuel mixtures.

Abstract Breakthrough alternative technologies are urgently required to alleviate the critical need to decarbonise our energy supply. We showcase non-conventional approaches to battery and solar energy conversion and storage (ECS) system designs that harness key attributes of immiscible electrolyte solutions, especially the membraneless separation of redox active species and ability to electrify certain liquid–liquid interfaces. We critically evaluate the recent development of membraneless redox flow batteries based on biphasic systems, where one redox couple is confined to an immiscible ionic liquid or organic solvent phase, and the other couple to an aqueous phase. Common to all solar ECS devices are the abilities to harvest light, leading to photo-induced charge carrier separation, and separate the products of the photo-reaction, minimising recombination. We summarise recent progress towards achieving this accepted solar ECS design using immiscible electrolyte solutions in photo-ionic cells, to generate redox fuels, and biphasic “batch” water splitting, to generate solar fuels.

The effects of climate dynamics on urban areas involve the aggravation of existing conditions and the potential for emergence of new hazards or risk factors. Floods are recognized as a leading source of consequences to society, including disruption of critical functions in urban areas, and to the environment. Consideration of the interplay between services providers ensuring urban functions is essential to deal with climate dynamics and associated risks. Assessment of resilience to multiple hazards requires integrated and multi-sectoral approaches embracing each strategic urban sector and interactions between them. A common limitation resides in the limited data and tools available for undertaking these complex assessments. The paper proposes a methodology to undertake the spatial characterization of the flood related hazards and exposure of both essential functions and services providers in urban areas, in the context of limitations in data and in ready-to-use tools. Results support the resilience assessment of these hazards, taking into account interdependencies and cascading effects. The approach is applied to Lisbon city as the study case. Results are promising in demonstrating the potential of combining data and knowledge from different sources with dual modelling approaches, allowing us to obtain trends on the magnitude of effects of climate scenarios and to assess potential benefits of adaptation strategies. Quantification of the effects is reached, but results need to be assessed together with the underlying levels of uncertainty. The methodology can facilitate dialogue among stakeholders and between different decision levels.

Bio-based and biodegradable plastics (BBPs) are innovative materials, wholly or partially produced from biomass, with the potential to enhance the circulation of resources in the biological cycle of the Ellen MacArthur Foundation’s butterfly diagram. Although BBPs are generally considered more environmental-friendly than conventional plastics, robust scientific evidence is still missing. The lack of tools and metrics to assess the circularity and sustainability of the BBPs industry poses relevant challenges for its upscaling and contribution to climate neutrality goals in Europe. It calls for adopting system and life cycle thinking, guided by multi-level and multi-dimensional examinations, which led researchers to build a comprehensive picture of trends, gaps and future orientations that may boost a sustainable circular bioeconomy in the sector. The value- chain based and multi-faceted SWOT analysis that emerged from the intersection of system and corporate data reveals the need to establish a combined circular bioeconomy strategy where incentives to integrated local supply chain, dedicated EPR scheme, eco-design guidelines, revised EoL standards, new clear labelling schemes and harmonised sustainability criteria should be prioritized and conjointly pursued to accelerate the transition towards a sustainable circular bioeconomy of the BBPs value chain. European Journal of Social Impact and Circular Economy, V. 4 N. 2 (2023)

Nowadays, organic aerogels have arisen as promising materials for different applications such as: building, construction, energy among others, due to their low density, high thermal insulation capacity and high porosity. In the recent years multiple procedures to synthesize them have been developed, however, the freeze-drying method has gained more importance, being considered a cost-competitive, eco-friendly, and efficient process. Therefore, it is fundamental to evaluate its environmental impacts for its future implementation as a sustainable industrial process. In this work, a Life Cycle Assessment on the synthesis of nanoclay reinforced polyvinyl alcohol aerogels by freeze-drying has been carried out. Furthermore, the influence of the production scale (laboratory and pilot line) and the functional unit (1 kg and 1 m3) have been studied. Additionally, different upgrading approaches carried out in the pilot line, energy efficiency and production capacity, have been evaluated. Results demonstrated that better environmental impact values were obtained with pilot line aerogel production in comparison to laboratory scale for both functional units. Regarding the different upgrade assessment with the pilot line, it has been concluded that the background processes and the energy consumption are the main causes for the increment in the environmental impact values during the aerogel synthesis. En la actualidad, los aerogeles orgánicos han surgido como materiales promisorios para diferentes aplicaciones tales como: edificación, construcción, energía entre otras, debido a su baja densidad, alta capacidad de aislamiento térmico y alta porosidad. En los últimos años se han desarrollado múltiples procedimientos para sintetizarlos, sin embargo, el método de liofilización ha ganado mayor importancia, siendo considerado un proceso rentable, amigable con el medio ambiente y eficiente. Por lo tanto, es fundamental evaluar sus impactos ambientales para su futura implementación como un proceso industrial sostenible. En este trabajo se ha llevado a cabo un análisis del ciclo de vida de la síntesis de aerogeles de poli(alcohol vinílico) reforzados con nanoarcillas mediante liofilización. Además, la influencia de la escala de producción (laboratorio y línea piloto) y la unidad funcional (1 kg y 1 m 3) han sido estudiados. Adicionalmente, se han evaluado diferentes enfoques de mejora llevados a cabo en la línea piloto, eficiencia energética y capacidad de producción. Los resultados demostraron que se obtuvieron mejores valores de impacto ambiental con la producción de aerogel en línea piloto en comparación con la escala de laboratorio para ambas unidades funcionales. En cuanto a la evaluación de diferentes actualizaciones con la línea piloto, se ha concluido que los procesos de fondo y el consumo de energía son las principales causas del incremento en los valores de impacto ambiental durante la síntesis del aerogel.