Carbonates
Mostrando 1-12 de 91 artigos, teses e dissertações.
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1. Characterization of a complex carbonate-silicate apatite ore and its concentration by a two-stage anionic flotation method
Abstract A carbonate-silicate low weathering phosphate ore from an igneous origin deposit in Southeastern Brazil presents a challenge mainly for apatite flotation from its gangue minerals, calcite and dolomite, plus the presence of phlogopite, diopside, magnetite, richterite, ilmenite, vermiculite, quartz and many other minor impurities. Recently, selectivit
REM - International Engineering Journal. Publicado em: 2022
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2. Purification of raw palygorskite: a comparative study involving different processes and dispersing agents
Abstract Palygorskite (Pal) is a natural clay mineral with fibrous morphology and high surface area. Depending on the geological origin, it presents impurities, such as quartz and carbonates, which can harm some of its properties. Therefore, this work seeks to define a viable methodology for the purification of a Brazilian Pal. Two types of mixing processes
Cerâmica. Publicado em: 2021-06
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3. Geomechanical characterization of carbonates of the Sete Lagoas Formation (Bambuí Group)
Abstract The geomechanical properties of rock masses must be identified to assess their quality and employability; however, the methodologies may differ depending on the lithotype and analytical purposes. The present study aimed to estimate the not-well-known physical-mechanical properties of three types of carbonate rocks (calcarenite, calcilutite, and marb
REM, Int. Eng. J.. Publicado em: 2020-03
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4. BIODIESEL SYNTHESIS FROM WASTE COOKING OIL USING A VARIETY OF WASTE MARBLE AS HETEROGENEOUS CATALYSTS
Abstract The research article is based on biodiesel synthesis by the transesterification of waste cooking oil with methanol in the presence of heterogeneous catalysts prepared from different marble. Eight samples of marble were successfully converted into potential catalysts by calcination. The thermal treatment of waste marbles at 300oC-1000oC converted the
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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5. Application of Glycerol in the Synthesis of Hyperbranched and Highly Branched Polyethers: Characterization, Morphology and Mechanism Proposal
Hyperbranched biopolymers is an important class of polymer that is used in different areas, mainly in biomedicine. AB2 monomers are crucial to the development of a "hyperbranched" architecture of polyglycerol, being glycidol the most commonly used, even considering its environmental hazard. Glycerol carbonate is an ecologically accepted monomer synthesized d
Mat. Res.. Publicado em: 24/10/2019
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6. Soil-applied Zn effect on soil fractions
ABSTRACT The interaction of Zn with soil compartments influences its bioavailability and uptake by plants. In this study, rice and soybean were cultivated under greenhouse conditions with the aim of evaluating Zn bioavailability and fractionation in a clayey-textured Typic Hapludox as a function of Zn rates (4 or 8 mg kg –1 Zn). The experiment was conducte
Sci. agric. (Piracicaba, Braz.). Publicado em: 02/09/2019
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7. Apatite multi-generations in the Três Estradas Carbonatite, Southern Brazil: physical and chemistry meaning and implications to phosphate ore quality
Abstract Carbonatites were recently discovered in Southern Brazil, which increased the interest to evaluate the economic potential of these uncommon rocks, especially the Três Estradas Carbonatite. Carbonates are the dominant minerals of fresh rock followed by apatite, but the weathering process makes apatite abundant. We focused on apatite from the carbona
Braz. J. Geol.. Publicado em: 01/07/2019
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8. Pre-concentration potential evaluation for a silicate zinc ore by density and sensor-based sorting methods
Abstract Pre-concentration consists of the preliminary discarding of a fraction of the mineral processing plant feed which contains little or none of the mineral of interest, reducing the mass to be processed in downstream operations (e.g. milling, concentration and dewatering), as well as the capital and operational costs. In this context, this study invest
REM, Int. Eng. J.. Publicado em: 2019-06
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9. Geochemistry, metamorphic evolution and tectonic significance of metabasites from Caçapava do Sul, southern Brazil
Abstract This paper proposes the generation and closure of a proto-ocean and formation of an island arc in the Neoproterozoic Passo Feio Metamorphic Complex (PFMC), Caçapava do Sul region, southern Brazil. The PFMC, São Gabriel Terrane, consists of a Neoproterozoic supracrustal metavolcano-sedimentary sequence intruded by the Caçapava Granite. The study u
Braz. J. Geol.. Publicado em: 29/04/2019
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10. Precipitación de uranio a partir de licores alcalinos
ABSTRACT In Argentina there is uranium with abundant organic matter and variety in quantity of sulfides and carbonates which act as cement or sealing joints. The latter minerals modify directly the choice of metal leaching process for the concentration of uranium. The most beneficial selected process turns out to be the alkaline leaching. Once this process h
Matéria (Rio J.). Publicado em: 19/07/2018
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11. FIXAÇÃO DE CO2 EM EFLUENTE SALINO DE INDÚSTRIA PETROQUÍMICA
In various industrial processes, such as the process of obtaining potassium by solution mining or in the oil industry, fuels are burnt concurrently to the formation of saline effluents. The opportunity to sequester carbon through capturing the CO2 from the flue gas by carbonation of these effluents and reducing the potential of scaling of the water is eviden
Quím. Nova. Publicado em: 2017-08
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12. Paleoenvironmental Evolution of Continental Carbonates in West-Central Brazil
ABSTRACT This paper presents a sedimentological and stratigraphical study of Quaternary (Middle to Late Pleistocene/Holocene) continental carbonates outcrops inside Pantanal Basin and its surroundings, especially in Serra da Bodoquena, Pantanal do Miranda and Corumbá/Ladário plateau, in the state of Mato Grosso do Sul, as well as in Serra das Araras, in th
An. Acad. Bras. Ciênc.. Publicado em: 04/05/2017