Repositório do LNEG
Repositório Científico do Laboratório Nacional de Energia e Geologia
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Marine biomineralization as MICI process. A basis for new anticorrosion surface treatments [Comunicação oral]
Publication . Marques, Maria João; Zanna, Sandrine; Marcus, Philippe; Basseguy, Regine
ABSTRACT: The development of sustainable corrosion protection strategies is a major challenge in materials engineering, particularly for metallic structures exposed to marine environments. While microorganisms are traditionally regarded as contributors to corrosion processes, their potential role in Microbiologically Influenced Corrosion Inhibition (MICI) remains largely underexplored. The objective of this presentation is to highlight the potential of MICI mechanisms as a novel pathway for corrosion protection solutions, with particular emphasis on biomineralization processes.
Atmospheric Corrosion Resistance of Marine Biomineralized Layers on Aluminium – Magnesium Alloy [Comunicação oral]
Publication . Marques, Maria João; Mercier, Dimitri; Seyeux, Antoine; Zanna, Sandrine; Marcus, Philippe; Basseguy, Regine
ABSTRACT: Developing solutions to improve the durability of materials remains a key challenge in surface science, especially for aluminium and aluminium alloys. In this context, marine biomineralization processes have been shown to offer potential as a novel approach for developing more sustainable corrosion protection solutions [1,2]. These solutions are based on the spontaneous formation of biomineralized layers, which exhibit a hybrid inorganic-organic nature and are capable of mitigating the corrosion of aluminium alloys, specifically Al-Mg alloys [3,4]. The present study investigates the corrosion resistance, under natural atmospheric exposure conditions, of marine biomineralized layers formed on Al-Mg surfaces. More specifically, the evaluation tests were carried out at an outdoor marine/industrial test site (Sines, Portugal). Morphological and chemical characterizations were performed before and after the exposure, mainly by SEM/EDX and XPS, enabling the assessment of the Al-Mg surface modifications and the impact of the natural atmospheric corrosion test on the biomineralized layer.
Metals recovery from end-of-life Li-ion batteries by physical processing and hydrometallurgical treatment [Poster]
Publication . Moço, Duarte; Morais, F.; Almeida, Joana; Neiva Correia, Maria Joana; Margarido, Fernanda; Pedrosa, Fátima; Plancha, Maria João; Gonçalves, Ana; Nogueira, Carlos
ABSTRACT: The growing demand for lithium-ion batteries (LIB) for electric mobility and energy storage applications has created enormous pressure on the metals market, not only for lithium (Li) but also for other critical metals such as nickel (Ni), cobalt (Co) and manganese (Mn). Beyond the need for primary extraction of mineral resources, which is essential for an initial phase of significant growth in demand, recycling will quickly play a fundamental role in the availability of these raw materials. Recycling also allows a valuable contribution to the management of end-of-life batteries (Dobó et al., 2023). Recycling of LIB is predominantly conducted through hydrometallurgical methods, involving both physical/mechanical processes (such as electrode fraction concentration) and chemical processes (including leaching, separation and recovery).
The physical operations include safe discharge and dismantling, followed by shredding and separation of fractions (Sommerville et al., 2020). In hydrometallurgical processing, metals are leached and recovered from aqueous solutions using different methods (Bae and Kim, 2021). This work presents findings from research on the physical and chemical treatment of end-of-life LIB (Ni-Co-Mn or NCM type), with an emphasis on the obtained recoveries and yields.
Lithium Recovery from Spodumene via Calcium Chloride-Assisted Roasting [Comunicação oral]
Publication . Almeida, Joana; Pedrosa, Fátima; Plancha, Maria João; Gonçalves, Ana; Nogueira, Carlos
ABSTRACT: In 2024, total energy-related CO₂ emissions increased by 0.8% compared with the previous year, reaching a record of 37.8 Gt CO₂. The transportation sector accounts for approximately one-third of global greenhouse gas emissions, where electrification is expected to play a crucial role in mitigation. Electric vehicles (EV) alone avoided 80 Mt of CO₂ emissions during the past year, highlighting the environmental benefits of transitioning to electric mobility (International Energy Agency, 2025). In this context, lithium (Li) is a key element in the global energy transition, primarily due to its use in EV battery components. However, Li is classified as critical raw material in the EU list due to its economic relevance and supply risk (European Commission, 2024). Ensuring that Li production is reliable and sufficient to meet the growing demand for modern technologies is essential for achieving long-term reductions in global CO₂ emissions. Conventional Li recovery from Li-bearing ores relies on metallurgical methods that consume high amounts of energy, with processing temperatures reaching up to 1100 °C, contributing to CO₂ emissions increase. These processes also generate co-products and solid waste, such as silicates and metal sulphates, which require additional purification steps, increasing both complexity and cost. The use of sulfuric acid (H₂SO₄) for ore digestion introduces further challenges, including corrosiveness, the need for frequent equipment maintenance and the release of harmful gases. From an environmental perspective, these operations may contribute to air pollution, acidification and wastewater generation.
Coupling hydrometallurgy and electrochemistry for lithium recovery and compound production [Comunicação oral]
Publication . Almeida, Joana; Pedrosa, Fátima; Plancha, Maria João; Gonçalves, Ana; Nogueira, Carlos
ABSTRACT: Global CO₂ emissions reached 38.11 Gt CO₂ in 2025 (Statista, 2026). The transport sector contributes significantly to these emissions. Therefore, the ongoing energy transition in the European Union (EU) has increased pressure on the resources required for electric vehicle production, particularly critical raw materials used in batteries, such as lithium (Li) (Dong et al., 2026). To reduce the dependence of EU on external suppliers, efforts are being made to decentralize Li production and develop synergies with active industrial processes. In Portugal, it is envisaged the potential implementation of an industrial-scale Li refining facility based on a membrane electrolysis process, feeding LiCl and producing high-purity battery-grade Li compounds. The aim of this work was to produce LiCl from α-spodumene, an important Li-bearing mineral, using more sustainable hydrometallurgical processes. The produced LiCl via extractive metallurgy could then be used in electrolysis processes to maintain chlorine production, that is needed for several commercial applications. By replacing conventional NaCl with LiCl, the process also provides a precursor for other important Li compounds to the energy transition, such as Li₂CO₃ and LiOH. Therefore, hydrometallurgical routes were studied to maximize LiCl recovery from α-spodumene (Li = 3.2%) while minimizing reagent consumption and energy use. A maximum of 91% of Li was recovered, when conventional calcination and H2SO4 digestion was replaced by CaCl2 roasting. This work highlights the potential of integrating hydrometallurgical processes with electrochemical routes to produce diverse Li compounds with lower environmental impacts.