Pyrite
Mostrando 1-12 de 101 artigos, teses e dissertações.
-
1. Role of the reducing agent in tungsten extraction by chlorination with chlorine from an ore enriched by physical means
Abstract The effect of three reducing agents (sulphur dioxide, pyrite and carbon) on tungsten extraction from a scheelite-wolframite concentrate with chlorine gas was assessed. A low-grade ore (0.9% w/w WO3) was collected in the San Martín department, San Luis Province, Argentina, and subsequently enriched by physical means (65.73% w/w WO3). The minerals id
REM - International Engineering Journal. Publicado em: 2022
-
2. FAST DETERMINATION OF THE SULFUR SPECIES IN SOLID PHASE SYSTEMS BY A TPO-IR METHOD
Qualitative and quantitative assessment of total sulfur and sulfur species in solid phase is necessarily important for development of effective desulfurization methods, reduction of environmental pollution, and prevention of catalyst poisoned. In this work, TPO-IR (Temperature Programmed Oxidation- Infrared) method was used for rapid determination of sulfur
Quím. Nova. Publicado em: 2021-01
-
3. Long-term behavior of mortars produced with sulfide-bearing aggregates
ABSTRACT The variety of sulfides (inorganic compounds formed by combining sulfur with a metal element) presented in earth crust is not small, which makes it difficult to avoid the use of sulfide-bearing aggregates in the concrete, especially in places where another source of material is non-existent or economically impracticable, as is the case of dams. With
Matéria (Rio J.). Publicado em: 25/11/2019
-
4. EFFECT OF Acidithiobacillus thiooxidans-CYSTEINE INTERACTIONS ON PYRITE BIOOXIDATION BY Acidithiobacillus ferrooxidans IN THE PRESENCE OF COAL COMPOUNDS
Abstract This study evaluated the biooxidation of pyrite contained in a Colombian coal (2.38 mm < particle size < 0.50 mm). The variables were cysteine concentration (0-600 mg/L) and culture type (pure Acidithiobacillus ferrooxidans (ATCC 23270) and a consortium of Acidithiobacillus thiooxidans (ATCC 15494) and Acidithiobacillus ferrooxidans). Pyrite oxidati
Braz. J. Chem. Eng.. Publicado em: 30/09/2019
-
5. Pyrite utilization in the carboniferous region of Santa Catarina, Brazil - Potentials, challenges, and environmental advantages
Abstract The main coal seams explored in the coal region of Santa Catarina are Barro Branco (BB) and Bonito (BO). Owing to the association with the mineral matter, the tailings generated in the beneficiation are arranged in disposal areas, and subject to the generation of acid mine drainage (AMD). The objective of this study was to evaluate the use of pyrite
REM, Int. Eng. J.. Publicado em: 19/06/2019
-
6. Long-term behavior of mortars produced with sulfide-bearing aggregates
ABSTRACT The variety of sulfides (inorganic compounds formed by combining sulfur with a metal element) present in earth crust is not small, which makes it difficult to avoid the use of sulfide-bearing aggregates in the concrete, especially in places where another source of material is non-existent or economically impracticable, as is the case of dams in Braz
Matéria (Rio J.). Publicado em: 10/06/2019
-
7. Evaluation of the Rietveld method for the mineralogical characterization of airborne dust in a mining area
Abstract In this article, we present the results of the mineralogical quantification of airborne dust from an urban area located in the Brazilian state of Minas Gerais in the vicinity of a gold mine. Three samples were collected at different points to assess spatial consistency. Results showed that the mineralogy, in relation to both major minerals and acces
REM, Int. Eng. J.. Publicado em: 2019-06
-
8. The Cristalino IOCG deposit: an example of multi-stage events of hydrothermal alteration and copper mineralization
Abstract The Cristalino deposit is located 40 km east of Sossego mine, Carajás. The orebody lies along a NW-SE-striking shear zone and is mainly hosted by the Neoarchean bi-modal volcanics of the Grão Pará Group. Field work and petrographic data seconded by SEM-EDS analysis allowed recognizing an early sodic metasomatism that was followed by calcic-ferric
Braz. J. Geol.. Publicado em: 15/04/2019
-
9. Microfacies and diagenetic evolution of the limestones of the upper part of the Crato Formation, Araripe Basin, northeastern Brazil
Abstract This paper presents the results of a petrographic and diagenetic study of the laminated limestones of the upper part of the Aptian to Albian Crato Formation, northeast of Brazil. The applied techniques were optical microscopy, cathodoluminescence and scanning electron microscopy (SEM) coupled to a wavelength-dispersive spectrometer (WDS). Petrograph
Braz. J. Geol.. Publicado em: 08/04/2019
-
10. Understanding the Surfaces and Crystal Growth of Pyrite FeS2
Pyrite is a common sulfide mineral, which has arisen early interest by its euhedral shape and by its metallic glow similar to gold. However, it is only in our century that we began to understand pyrite crystal growth, considering the thermodynamic and kinetic aspects of crystal formation as a function of temperature and concentration of the elements present
Mat. Res.. Publicado em: 14/11/2018
-
11. Thermal Behavior of Pyrite in the CO2 and N2 Atmosphere for Obtaining Pyrrhotite: A Magnetic Material
In the southern of Brazil the coal is composed of a large amount of pyrite (FeS2), an environmental problem for this region because the pyrite turns a waste. This work investigated the behavior of pyrite in CO2 and N2 atmospheres, aiming to identify better thermal treatment conditions of the pyrite waste that favor obtaining a material with magnetic properti
Mat. Res.. Publicado em: 18/10/2018
-
12. The Iron Sulfides Crystal Growth from the Halide Melts
A new approach to a single crystals growth of the iron sulfide phases of definite structure and nonstoichiometry is developed and applied. This approach is based on the method of crystal growing from solution melts. This approach is based on the crystallization or recrystallization of iron sulfides from iron sulfide solutions in iron dihalide melts under fix
Mat. Res.. Publicado em: 21/05/2018