ME - Comunicações em actas de encontros científicos internacionais
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- Marine biomineralization for enhanced corrosion resistance: Insights from the ANR MICOATEC project [Poster]Publication . Marques, Maria João; Nkoua, C.; Jaume, Julien; Diderot, Anthony; Mercier, Dimitri; Seyeux, Antoine; Délia, Marie-Line; Silva, S. da; Fori, B.; Blanc, C.; Zanna, Sandrine; Marcus, Philippe; Basseguy, RegineABSTRACT: Concerns about marine pollution and ecological threats caused by traditional corrosion protection technologies have driven the development of new environmentally friendly anti-corrosion solutions. In recent years, it became clear that microorganisms have the potential to positively impact corrosion behavior, a phenomenon known as MICI (microbiologically influenced corrosion inhibition) [1,2]. Although research on MICI mechanisms is still in the beginning, two main mechanisms have been outlined: direct and indirect inhibition. In the first one, the microorganisms are responsible for the segregation of slow-release inhibitors or surfactants or consume oxygen, which affects the cathodic reaction process. The second one, indirect inhibition mechanism, is associated to the formation of a protective layer on the surface of the material due to metabolic activity of microorganisms. In this context, biomineralization attracted the attention of researchers as a solution to inhibit metal corrosion.
- Marine Microbial Induced Mineralization: Exploring Mechanisms for Bioinspired Anticorrosion solutionsPublication . Marques, Maria João; Zanna, Sandrine; Marcus, Philippe; Basseguy, RegineABSTRACT: In the field of corrosion, nature has proved to be a source of inspiration for developing new green protection concepts. Over the last decades, new emerging microbial-based technologies have been studied, based on the recognition that microorganisms can influence corrosion behaviour in an advantageous way, the so-called MICI (microbiologically influenced corrosion inhibition), opening different lines of research (1-5). In particular, the process of biomineralisation on the surface of materials was recently highlighted as a promising new environmentally-friendly approach to produce protective coatings.
- Potential for hydrogen production associated to water and food in off-grid communities of Southern AfricaPublication . Rodrigues, Luiz; Araujo, Luis; Gano, António; Pinto, P.J.R.; Simoes, Sofia; Brito, Paulo; Monjane, Armindo; Rangel, C. M.ABSTRACT: Solar energy is called to meet electricity demands for isolated, off-grid communities in Africa. However, solar electric energy is intermittent and can be stored, for a limited amount of time, in batteries, which are expensive and cause serious environmental impacts at the end of their lifetime. Conversion of the surplus electric energy to green hydrogen through water electrolysis and back to electricity, when needed, using electrolyser-fuel cells systems, is examined as a potential solution to meet the water-energy-food nexus in Southern Africa. In the framework of the Agrivoltaics concept, the main constrains, opportunities and parameters to consider its applicability are presented and discussed, in terms of its technical, economic, environmental and social impacts. In the second phase of this work the developing of a PEM electrolyser for connection to a solar PV power source and a fuel cell device, for a stand-alone application, is proposed, ensuring high reliability and energy conversion efficiencies, as well as adequate transient response and a competitive cost. It is intended as a low-carbon energy system, realising the potential for synergy in the Agrivoltaic concept, aligned with global and regional sustainability goals.
- A Distributed Smart Battery Management System: sBMS, for Stationary Energy Storage ApplicationsPublication . Gano, António; Rangel, C. M.ABSTRACT: Currently, electric energy storage systems for stationary applications have known an increasing interest, namely with the integration of local renewable energy power sources into energy communities. Li-ion batteries are considered the leading electric storage devices to achieve this integration, and Battery Management Systems (BMS) are decisive for their control and optimum performance. In this work, the advancement of a smart BMS (sBMS) prototype with a modular distributed topology is described. The system, still under development, has a distributed architecture, with modular characteristics, to operate with different battery pack topologies and charge capacities, integrating adaptive algorithms for functional state real time monitoring and management of multicellular Li-ion batteries, and is intended for application in the context of a local energy community fed by renewable energy sources.
- Potential for hydrogen production associated to water and food in off-grid communities of Southern Africa [Resumo]Publication . Rodrigues, Luiz; Araujo, Luis; Gano, António; Pinto, P.J.R.; Simoes, Sofia; Brito, Paulo; Monjane, Armindo; Rangel, C. M.ABSTRACT: Solar energy is called to meet electricity demands for isolated, off-grid communities in Africa. However, solar electric energy is intermittent and can be stored, for a limited amount of time, in batteries, which are expensive and cause serious environmental impacts at the end of their lifetime. Conversion of the surplus electric energy to green hydrogen through water electrolysis and back to electricity, when needed, using electrolyser-fuel cells systems, is examined as a potential solution to meet the water-energy-food nexus in Southern Africa. In the framework of the Agrivoltaics concept, the main constrains, opportunities and parameters to consider its applicability are presented and discussed, in terms of its technical, economic, environmental and social impacts. In the second phase of this work the developing of a PEM electrolyser for connection to a solar PV power source and a fuel cell device, for a stand-alone application, is proposed, ensuring high reliability and energy conversion efficiencies, as well as adequate transient response and a competitive cost. It is intended as a low-carbon energy system, realising the potential for synergy in the Agrivoltaic concept, aligned with global and regional sustainability goals.
- Pre-treatment operations envisaging the processing of spent Li-ion batteries by hydrometallurgyPublication . Nogueira, Carlos; Margarido, F.ABSTRACT: In the recycling of spent batteries by hydrometallurgy, the pre-metallurgical processing is a crucial step to produce a concentrate (black-mass) rich in electrode materials, namely the cathode powders containing the metals Li, Ni, Co and Mn. In this paper, a series of operations including drying, thermal treatment, grinding and sieving were proposed and tested. Drying allowed to remove efficiently the solvent from the electrolyte while thermal treatment was effective in removing the binder and allowing the release of electrode powders during grinding of the electrode sheets. As a result, 98% of the cathode materials containing the valuable metals were recovered in the fine fraction (below 0.5 mm) with low Al and Cu contamination from the foils. These fines constitute a valuable black-mass to be treated by hydrometallurgy.
- Study of the degradation of Nafion modified membranesPublication . Teixeira, Fatima; Teixeira, António P. S.; Rangel, C. M.ABSTRACT: The development of new proton exchange membranes for PEM technology in fuel cells and electrolysers with increased durability is paramount to system´s lifetime and scalability. In this work, new modified Nafion membranes are proposed with increased resilience to chemical degradation by H2O2 /Fe2+, mimicking ex-situ radical attack to membrane structure.
- Metal hydride-based hydrogen production and storage system for stationary applications powered by renewable sourcesPublication . Rangel, C. M.; Fernandes, Vitor; Gano, AntónioABSTRACT: The development of systems for production and storage of hydrogen as an energy vector for various applications, has gained much relevance in recent years as it is considered critical in the increase of renewable energies in the energy mix. Presently, most part of the hydrogen production using renewable energy sources is based on electrolysis systems that use water to obtain green hydrogen, that can be stored and later used or converted to electrical energy using fuel cells. New laboratory reactor systems for the production and storage of hydrogen using metal hydrides have been demonstrated in recent years, making these kind of reversible electrochemical systems alternative future options for the production and storage of hydrogen.
- New proton conductive membranes of indazole- and condensed pyrazolebisphosphonic acid-Nafion membranes for PEMFCPublication . Teixeira, Fatima; Teixeira, António P. S.; Rangel, C. M.ABSTRACT: The global demands of energy are still increasing alongside many civilizational problems, notably the effects on the environment due to the overuse of traditional energy sources based on fossil fuels. New cleaner, renewable sources for sustainable energy systems are a key challenge of the 21st century society.
- Synthesis and characterization of new azaheterocyclic aromatic phosphonates for hybrid materials for fuel cell applicationsPublication . Teixeira, Fatima; Rangel, C. M.ABSTRACT: This work reports the synthesis and characterization of new azaheterocyclic aromatic phosphonates derivated from benzimidazole and benzotriazole by nickel-catalyzed Arbuzov reaction of 4,7-dibromo-2,1,3-benzothiadiazole with triethyl phosphite, followed by reductive sulfur extrusion reaction and cyclization. The compounds were characterized by NMR and mass spectrometry (low and high resolution). These azoles will be incorporated into proton conductive inorganic-organic hybrid membranes of mesoporous silica to produce novel membranes materials with high proton conductivity for intermediate temperature PEMFCs.