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- Valorização de recursos minerais : contribuição do projecto MinReMol para uma recuperação sustentável do rénio a partir de resíduos mineirosPublication . Silva, Teresa; Figueiredo, M. Ondina; Santos, Renata; de Oliveira, Daniel Pipa Soares; Veiga, JP; Batista, Maria Joao
- Environmental assessment of Ni and Cd in topsoil and ground-level dust from urban playgrounds, public gardens and parks from Lisbon, PortugalPublication . Reis, Amélia; Patinha, Carla; Silva, Eduardo Ferreira da; Dias, Ana; Bartolomeu, Sofia; Sousa, António; Cachada, Anabela; Batista, Maria Joao; Prazeres, Cátia; Figueira, Rui; Sergio, Cecilia; Salgueiro, Rita; Neves, Orquídea; Duarte, Armando
- Towards the recovery of by-product metals from mine wastes : an X-Ray absorption spectroscopy study on the binding state of rhenium in debris from a centennial Iberian Pyrite Belt minePublication . Figueiredo, M. Ondina; Silva, Teresa; Veiga, JP; de Oliveira, Daniel Pipa Soares; Batista, Maria JoaoRhenium is a very scarce element, occurring in the Earth's crust mainly carried by molybdenite (MoS2). Due to a very low availability comparative to actual industrial demand, rhenium is nowadays one of the most expensive mineral commodities and an increased interest is focused on exploring residues resulting from a long-term mining, particularly of sulphide ore deposits. It is therefore noteworthy to assign the presence of rhenium (in a concentration up to 3 ppm) in the waste materials from the old sulphur factory at the abandoned mine of São Domingos (Iberian Pyrite Belt, Southeast Portugal), exploited since the Roman occupation of Iberia. Aiming at a potential sustainable recovery of rhenium as a by-product, X-ray near-edge absorption spectroscopy (XANES) was applied to clarify the Re-binding and mode of occurrence by comparing Re L3-edge XANES spectra obtained from mine waste samples (previously fully characterized by X-ray laboratory techniques) with similar spectra collected from Re-rich molybdenites (Mo1-xRexS2) and from Re-O model compounds configuring various valences and coordination environments of rhenium ions. Obtained results are commented, ruling out a possible Re-S binding and rather conforming with the binding of rhenium to oxygen in the analysed mine waste materials.
- Carta geoambiental da região da Grande BeiraPublication . Oliveira, José Tomás; Milisse, Dino; Daudi, Elias Félix; Ramalho, Elsa; Fernandes, Judite; Quental, Lídia; Batista, Maria Joao; Dias, Ruben Pereira; Ussene, Ussene Vasco; Magaia, Almiro; Muchanga, André; Muchibane, Aníbal; Zeferino, Cátia Lídia; Balate, Gabriel; Gomane, Gertrudes; Cune, Grácio; Rebêlo, Luís Pina; Nave, Silvia; Manhiça, Vladimiro; Pereira, Aurete
- Geofísica aplicada à gestão da água subterrânea e ao ordenamento do território da cidade da BeiraPublication . Daudi, Elias Félix; Ramalho, Elsa; Fernandes, Judite; Batista, Maria Joao; Quental, Lídia; Dias, Ruben Pereira; Milisse, Dino; Ussene, Ussene Vasco; Oliveira, José Tomás; Cune, Grácio; Balate, Gabriel; Manhiça, Vítor
- Análise expedita de U e de razões Zr/Rb em solos e relação com a componente geológica na região de Nisa-Castelo de Vide, PortugalPublication . Prazeres, Cátia; Batista, Maria Joao; Silva, Teresa; Figueiredo, M. Ondina
- Resultados del proyecto GEMAS en la Península IbéricaPublication . Bel-Ian, A.; Locutura, Juan; Batista, Maria Joao; Martínez, S.
- Opportunities for recovering critical raw materials from mine wastes : the type-case of rhenium in residues from the exploitation of old portuguese minesPublication . Figueiredo, M. Ondina; Silva, Teresa; Batista, Maria Joao; Veiga, JP; de Oliveira, Daniel Pipa Soares
- Scarce industrial commodities : a glance at the possible rhenium availability in mining residues from the exploitation of Portuguese ore depositsPublication . Figueiredo, M. Ondina; Silva, Teresa; Batista, Maria Joao; de Oliveira, Daniel Pipa Soares; Veiga, JP
- Molybdenite as a rhenium carrier : first results of a spectroscopic approach using synchrotron radiationPublication . Silva, Teresa; Figueiredo, M. Ondina; de Oliveira, Daniel Pipa Soares; Veiga, JP; Batista, Maria JoaoThe chemical and physical properties of rhenium render it a highly demanded metal for advanced applications in important industrial fields. This very scarce element occurs mainly in ores of porphyry copper-molybdenum deposits associated with the mineral molybdenite, MoS2, but it has also been found in granite pegmatites and quartz veins as well as in volcanic gases. Molybdenite is a typical polytype mineral which crystal structure is based on the stacking of [S-Mo-S] with molybdenum in prismatic coordination by sulphide anions; however, it is not yet clearly established if rhenium ions replace Mo4+ cations in a disordered way or else, if such replacement gives rise to dispersed nanodomains of a rhenium-rich phase. As a contribution to clarify this question, an X-ray absorption spectroscopy (XANES) study using synchrotron radiation was performed at the Re L3-edge of rhenium-containing molybdenite samples. Obtained results are described and discussed supporting the generally accepted structural perspective that rhenium is mainly carried by molybdenite through the isomorphous replacement of Mo, rather than by the formation of dispersed Re-specific nanophase(s).