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1
Ortega-Osorio, A., and F. Paez-Osuna. "Composición geoquímica y mineralógica de los depósitos hidrotermales de la dorsal del pacifico mexicano (21°N) y la cuenca de Guaymas." Geofísica Internacional 28, no. 4 (October 1, 1989): 737–62. http://dx.doi.org/10.22201/igeof.00167169p.1989.28.4.1320.
Повний текст джерелаАнотація:
Se discuten la composición geoquímica y mineralógica de 24 muestras colectadas con el sumergible ALVIN en la Dorsal del Pacífico Mexicano (21°N) y la depresión sur de la Cuenca de Guaymas, Golfo de California. Los depósitos hidrotermales en los 21°N (tipo sulfuros) consisten primordialmente e sulfuros de Cu, Zn y Fe (esfalerita, pirita, marcasita, calcopirita y wurzita) con cantidades menores de sulfatos de Ca y Ba (anhidrita y barita) y vestigios de otros minerales. La composición metálica del interior de las chimeneas activas es: Cu 29.3%, Zn 0.7%, Fe 22.5% y del exterior: Cu 2.5%, Zn 10.3%, Fe 12.7%, en las chimeneas inactivas es: Cu 1.8%, Zn 7.3%, Fe 2.9%, Ca 25.3%, Mg 5.5% y en la superficie de los montículos: Cu 0.4%, Zn 6.0%, Fe 33.5%. En contraste con la región dorsal en los 21°N, los depósitos hidrotermales de la Cuenca de Guaymas presentan una mineralogía de sulfuros diferentes; pirrotita en el sulfuro más abundante, con cantidades menores de sulfuros de Zn, Cu, Fe, lo cual se refleja en su composición geoquímica.
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Carranza Edwards, Arturo, J. Eduardo Aguayo Camargo, and Leticia Rosales Hoz. "Actividad Hidrotermal Submarina y su Importancia en la Génesis de Sulfuros Minerales." Boletín de la Sociedad Geológica Mexicana 48, no. 1 (1987): 1–7. http://dx.doi.org/10.18268/bsgm1987v48n1a1.
Повний текст джерела
3
Huarachi-Olivera, Ronald, Alex Dueñas-Gonza, Ursulo Yapo, Moisés Almanza, Dennys Manuel, Antonio Lazarte-Rivera, Gelbert Mogrovejo-Medina, Homar Taco-Cervantes, and Mario Esparza. "Biolixiviación de mineral cuarzo por Acidithiobacillus ferrooxidans en reactor de columna por gravedad." Revista de Metalurgia 53, no. 2 (June 7, 2017): 096. http://dx.doi.org/10.3989/revmetalm.096.
Повний текст джерелаАнотація:
La biolixiviación es el proceso mediante el cual se extrae cobre de minerales sulfuros de baja ley usando microorganismos. La lixiviación química se aplica preferentemente para extraer cobre de minerales oxidados o mixtos, pero no existe información de aplicación de microorganismos en esta operación. En tal sentido, en la presente investigación se trabajó con reactores en columna por gravedad para procesos de lixiviación química, con cultivos bacterianos de Acidithiobacillus ferrooxidans en medio 9K y mineral de cuarzo que contenía cuprita y pirita, con diferentes tamaños de partícula. Se encontró que después de 24 días de lixiviación química se recuperó el 86% de cobre cuando se incluyeron bacterias, mientras que sin ellas sólo se recuperó el 54%. La mayor recuperación de cobre en ambos procesos se obtuvo en el siguiente orden de acuerdo al tamaño de partícula: 9,5 mm > 12,5 mm > 19,05 mm. Así, la aplicación de células bacterianas a procesos lixiviación química con minerales oxidados de cobre que incluyen cuarzo y células de A. ferrooxidans, aumenta la recuperación de cobre cuanto menor sea el tamaño de partícula del mineral. Esta tecnología puede ser utilizada por empresas mineras que aún siguen realizando lixiviación química convencional y se puede incluir en la operación la adición de microorganismos para aumentar la recuperación de cobre de minerales sulfurados incluyendo cuarzo.
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Arias Arce, Vladimir Alejandro, Daniel Florencio Lovera Dávila, Abad Flores Paucarima, and Tito Libio Sánchez Rojas. "Correlación del potencial óxido reducción y la población bacteriana durante el estudio de biolixiviación de sulfuros de cobre." Revista del Instituto de investigación de la Facultad de minas, metalurgia y ciencias geográficas 24, no. 47 (June 18, 2021): 19–28. http://dx.doi.org/10.15381/iigeo.v24i47.20639.
Повний текст джерелаАнотація:
Se estudio la correlación de las variables población bacteriana y potencial de óxido reducción (ORP) en la biolixiviación de minerales sulfurados mediante cepa bacteriana de Acidithiobacilus Ferrooxidans aisladas a partir de efluente ácido de mina, buscando la solubilización del cobre y la liberación del oro presente en un mineral con sulfuros superior a 80%. Las variables de experimentación fueron: La densidad de pulpa a 1, 2 y 6 % (W/V), concentración de sulfato ferroso como parte del medio 9k de 0, 3, 6, 9 y 15 gr/L; manteniendo constante la temperatura, agitación del medio y el pH. Los ensayos se realizaron en tres etapas consecutivas, iniciándose con inoculo conteniendo 7.05x107 Cel/mL y luego, la obtenida en cada etapa previa, observándose la variación en los periodos de adaptación y crecimiento. En la primera etapa la máxima población bacteriana alcanzada fue de 4.75x107 Cel/mL en 24 días con 6 g/L de sulfato ferroso. En la segunda etapa se obtuvo una máxima densidad de 6.30x107 Cel/mL sin la adición de sulfato ferroso. En la tercera etapa la densidad bacteriana alcanzada fue de 4.51x107 Cel/mL., con inicios de crecimiento exponencial aproximadamente a los 13, 8 y 3 días, respectivamente. Las cepas bacterianas fueron adaptadas satisfactoriamente en distintos medios conteniendo cantidades variadas de hierro y minerales sulfurados, dando mejores resultados sin la adición de sulfato ferroso.
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Martínez Rojo, Edgar, Aislinn Michelle Teja Ruiz, Martin Reyes Pérez, Miguel Pérez Labra, Gustavo Reyes Urbano, Francisco Raúl Barrientos Hernández, and Julio César Juárez Tapia. "Identificación de sulfuros complejos de plata (Sulfosales) contenidos en un concentrado de Pb, del distrito minero de Zimapán Hgo,." Tópicos de Investigación en Ciencias de la Tierra y Materiales 7, no. 7 (October 5, 2020): 19–23. http://dx.doi.org/10.29057/aactm.v7i7.6175.
Повний текст джерелаАнотація:
La caracterización mineralógica de un concentrado de plomo del distrito minero de Zimapán, Hidalgo, México, se realizó con la finalidad de identificar la presencia de sulfuros ternarios cuya prevalencia en el subproducto se atribuye a su naturaleza compleja. Estas especies minerales contienen una importante concentración de plata cuya extracción representa un importante valor agregado para el concentrado y su estudio abre pauta al desarrollo de nuevos procesos de lixiviación para la posterior recuperación del metal precioso. Para el proceso de caracterización se utilizó la combinación de varias técnicas analíticas como: Microscopia Óptica de Polarización (MOP), Microscopía Electrónica de Barrido (MEB) con espectrómetro de dispersión de energía (EDS) y Difracción de rayos X (DRX). Los resultados del análisis químico-granulométrico confirmaron la presencia de plata en una concentración promedio de 3.6 kg., y determinaron que la mayor distribución de plata en el concentrado se encuentra en el conjunto de partículas acotadas
Los resultados de la caracterización fueron complementados por cada una de las técnicas antes mencionadas y reportaron una mineralización argentífera, constituida principalmente por sulfosales de Ag como la tetraedrita, freibergita (Ag4.2As0.12Cu5.82Fe1.56S13Sb3.88Zn0.42), polibasita (Ag3.1As0.203CuS22Sb3.793), y en menor medida argentita (Ag2S), también se observó la presencia de metales base asociados en forma de sulfuros. La matriz de la muestra mineral corresponde a la galena (PbS).
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Granados Oliver, J. A., M. Reyes Pérez, A. M. Teja Ruiz, M. Pérez Labra, F. R. Barrientos Hernández, J. C. Juárez Tapia, and J. A. Cobos Murcia. "Caracterización espectroscópica de los sulfuros de zinc flotados en presencia de precipitados de hierro." Tópicos de Investigación en Ciencias de la Tierra y Materiales 6, no. 6 (October 5, 2019): 116–22. http://dx.doi.org/10.29057/aactm.v6i6.5020.
Повний текст джерелаАнотація:
Durante la molienda de sulfuros minerales en molinos de bolas, los elementos molturadores se oxidan y forman una variedad de óxidos, hidróxidos y oxi hidróxidos de hierro; previas investigaciones han establecido que la adsorción de estas especies al mineral contamina la superficie y afectan la etapa de flotación. En esta investigación, se estudió la flotación de esfalerita en presencia de precipitados de hierro férrico y ferroso en diferentes concentraciones, los productos de la flotación se caracterizaron por espectroscopia de infrarrojo por transformada de Fourier. Los resultados muestran que el incremento de la flotación, depende de la formación de óxidos de hierro con una banda de enlace en 619 cm-1 correspondiente a goetita y de los óxidos de zinc con bandas de enlace del Zn–O en 1737, 1378, 1244, y 1031 cm-1, Se detectó además una banda en 1120 cm-1 indicando la formación de ion sulfato tetragonal libre. Similares resultados de flotación y composición superficial se obtienen cuando se tiene 75 ppm de ion férrico o ion ferroso. La esfalerita pulverizada en mortero de ágata, exhibió bandas de enlace del Zn–O, y la formación de sulfatos enlazados de manera mono dentada con el zinc con tres bandas de absorción.
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Hidalgo Camarena, Prudencia, Pablo Espinoza Tumialan, and Rafael Figueroa Tauquino. "Ensayo de adaptación de especies vegetales para la cobertura vegetal de los relaves mineros de la planta concentradora Santa Rosa de Jangas." APORTE SANTIAGUINO 3, no. 1 (July 19, 2010): 18. http://dx.doi.org/10.32911/as.2010.v3.n1.416.
Повний текст джерелаАнотація:
Al concentrar minerales por flotación, se genera un relave conformado entre otros elementos por partículas finamente trituradas ele silicatos, arcillas, carbonatos, óxidos y eventualmente sulfuros conjuntamente, sin valor comercial, que se almacenan en depósitos denominados relaveras. El área seleccionada en la relavera de la planta concentradora "Santa Rosa de Jangas·• fue acondicionada y preparada adecuadamente con un sustrato de mezcla homogénea de tierra agrícola, turba y arena, sobre la cual se sembraron o trasplantaron las especies vegetales a evaluarse con la final iclacl de obtener datos para futuros trabajos de revegetación o fitoestabi lización en cierres de minas. La metodología consistió en evaluar las diferentes especies preseleccionadas en cuanto a profundidad ele raíces, biomasa, tamaño de planta, frecuencia, diámetro de tal lo y cobertura. Los resultados muestran que las especies mas adecuadas para la fitoestabilización de la supe1iicie de la relavera por sus diversas características favorables son el 'kikuyo · y la asociación ray grass - 'trébol
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Nieves Pimiento, Nayive, and Alix Solano Figueroa. "Caracterización del drenaje ácido en la mineria de esmeralda Quípama-Boyacá." Visión electrónica 11, no. 2 (December 17, 2017): 318–25. http://dx.doi.org/10.14483/22484728.13136.
Повний текст джерелаАнотація:
Los drenajes ácidos son derivados de la formación del proceso de algunos sulfuros minerales al contacto del oxígeno del aire y el agua, esta formación involucra procesos químicos, biológicos y fenómenos físico-químicos. Con el objetivo de caracterizar el drenaje acido en la minería esmeraldífera en el municipio de Quipama-Boyacá, se ha propuesto el estudio y análisis de los parámetros físico-químicos de aguas subterráneas para la mina Divino Niño. Para la determinación de las características del drenaje acido, se llevaron a cabo tomas in situ en el interior de la mina y las descargas. Los resultados obtenidos determinaron que; las aguas de los drenajes al interior de la mina presentaron transformaciones físicas, químicas y biológicas las cuales dieron origen a drenaje ligeramente acido de clase blanda, presentando aniones y cationes en disolución, se mostraron elevadas concentraciones de SO4, Fe, Al, Ca. Este fue un primer estudio desarrollado al interior de la mina de esmeralda Divino Niño en el municipio de Quipama.
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Arribas, A., and E. Figueroa. "Las mineralizaciones de uranio en las rocas volcánicas de Macusani. Puno (Perú)." Estudios Geológicos 41, no. 5-6 (December 30, 1985): 323. http://dx.doi.org/10.3989/egeol.85415-6714.
Повний текст джерелаАнотація:
Los caracteres petrográficos, mineralógicos y tectónicos de los indicios uraníferos de Macusani, situados 150 kilómetros al NNW del lago Titicaca, en Perú, hacen de estas mineralizaciones un caso único entre los yacimientos de U asociados con rocas piroclásticas. Así los estudios llevados a cabo demuestran que: 1. Los minerales de U se hallan principalmente en los niveles superiores de la pila volcánica. 2. Las rocas encajantes corresponden a ignimbritas riolíticas y riodacíticas, pliocuaternarlas, formadas por cuarzo, sanidina, oligoclasa, biotita y, ocasionalmente, moscovita y andalucita, en una matriz vítrea, parcialmente desvitrificada, que contiene numerosos c1astos de lutitas. 3. La biotita, cuarzo ahumado y andalucita son muy abundantes en los niveles mineralizados. 4. Los minerales metálicos se componen casi exclusivamente de pechblenda masiva, más o menos transformada en gummitas, fosfatos y silicatos de U, y muy escasos sulfuros de Fe. 5. La pechblenda rellena fracturas que miden entre unos centímetros y varios metros de longitud, y de 1 a 100 milímetros de anchura. Algunas de estas fracturas son subverticales y debidas a la contracción que dio lugar a la disyunción columnar. Otras son subhorizonta1es y paralelas a un sistema de cizallas dúctiles, conjugadas, que se desarrolló por compactación y asentamiento de los materiales piroclásticos que contienen la mineralización. De acuerdo con esos factores, se propone en este trabajo un modelo metalogénico preliminar para explicar el origen de este singular tipo de yacimientos de uranio.
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Gonzalez-Partida, E., and V. Torres-Rodriguez. "EVOLUCION TECTONICA DE LA PORCION CENTRO-OCCIDENTAL DE MEXICO Y SU RELACION CON LOS YACIMIENTOS MINERALES ASOCIADOS." Geofísica Internacional 27, no. 4 (October 1, 1988): 543–81. http://dx.doi.org/10.22201/igeof.00167169p.1988.27.4.810.
Повний текст джерелаАнотація:
Se demuestra la existencia de provincias o franjas metálicas en la porción centro-occidental de México cuya distribución y origen obedecen a los procesos tectónicos siguientes: Formación de un arco volcánico submarino con alto contenido de pelíticos en la zona de post-arco. La mineralización es sinsedimentaria de cobre-pirrotita en el arco y polimetálica en el post-arco. Estas rocas están afectadas por un metamorfismo epizonal de la facies de esquistos verdes. Se propone el nombre de "Secuencia Volcanosedimentaria Metamorfizada" para estas rocas cuya edad es Permo-Triásica.Magmatismo intrusivo calcoalcalino de margen continental y edad Jurásica que forma el batolito de Puerto Vallarta y algunas rocas intrusivas de Baja California. No se conocen mineralizaciones asociadas a estas rocas.Levantamiento, erosión y formación de deltas progradantes y desarrollo de yacimiento de origen químico asociados a sedimentos terrígenos con mineralizaciones de Pb, Zn, Ag.Formación de un arco de islas con cuenca marginal, creada a partir de una tectónica distensiva en la zona de post-arco. La edad del arco es Cretácico Temprano. Este marco geológico contiene los sulfuros masivos polimetálicos más importantes de México. Se propone el nombre de "Secuencia Volcanosedimentaria no Metamórfica" para este conjunto litológico.Migraciones laterales del magmatismo continental ocurridas entre el Cretácico Tardío y el Terciario Medio, quedando definidas las provincias metálicas del centro-occidente de México. Las asociaciones más importantes son: Fe (Ti, Cu, Sn); Cu, Au; Pb, Zn, Ag (Au, Cu); Au, Ag (Pb, Zn, Cu); Sn; CaF2; Mn y Hg, Sb (Mn). La distribución de estas franjas es semiparalela a la actual línea de costa y en varias de ellas se observan traslapes debidos a procesos heterocronos.En el Reciente se están desarrollando depósitos de placer en litorales y plataforma continental con mineralización de magnetita, hematita, rutilo y zircón.
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Misseri, Lucas, Francisco, A. Cellone, Pablo, J. Bouza, María del Pilar Alvarez, and Eleonora, S. Carol. "Geohidrología de un sector de la marisma de Bahía San Blas." Revista del Museo de La Plata 5, no. 2 (August 29, 2020): 500–509. http://dx.doi.org/10.24215/25456377e122.
Повний текст джерелаАнотація:
La marisma del arroyo Jabalí forma parte de la Reserva Natural Provincial de Uso Múltiple Bahía San Blas y se encuentra ubicada al sudeste de la provincia de Buenos Aires, Argentina. El objetivo del trabajo es analizar los principales procesos geohidrológicos que regulan la química del agua superficial y subterránea de este humedal y su relación con las características geomorfológicas y pedológicas. Para ello se realizó una caracterización geomorfológica en base a la cual se diseñó una red de monitoreo del agua superficial y subterránea. Se construyeron 14 freatímetros a lo largo de 3 transectas perpendiculares al arroyo y se recolectaron muestras de agua en las que se analizó in situ el pH y la conductividad eléctrica y se determinó en laboratorio el contenido de iones mayoritarios. Los datos fueron analizados mediante gráficos de relaciones iónicas y diagramas de clasificación de aguas. A su vez en cada sector estudiado se efectuaron calicatas para la descripción de los perfiles del suelo y características texturales de los sedimentos superficiales. Los resultados obtenidos muestran que tanto la química del agua del canal Jabalí como la subterránea de la marisma son dominantemente cloruradas sódicas, existiendo un enriquecimiento en el contenido iónico asociado a una mayor distancia con respecto a la boca del canal y una posición topográfica más elevada. El principal proceso que condiciona la química del agua subterránea es la disolución de especies minerales formadas en la superficie de los suelos por evaporación del agua de mar y la posterior incorporación en el acuífero por infiltración. Estos procesos se ven favorecidos por el clima semiárido, la menor recurrencia de inundación por posición topográfica elevada, y por la textura fina de los suelos. A su vez, la oxidación de sulfuros pedogenéticos y la consecuente acidificación del medio son propuestos como otros mecanismos que condicionan la química del agua.
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Rosales H, Jimmy, Carlos Rojas L, Fabricio Mansilla P., Joseps Andrade Ch., and José Castillo S. "UN MODELO ONTOLÓGICO PARA AYUDAR AL RECONOCIMIENTO DE MINERALES." Revista Cientifica TECNIA 26, no. 2 (March 5, 2017): 81. http://dx.doi.org/10.21754/tecnia.v26i2.60.
Повний текст джерелаАнотація:
El presente trabajo, está enfocado en el desarrollo de un modelo Ontológico para ayudar al reconocimiento de minerales sulfurados. Dicha Ontología se implementará siguiendo los métodos de construcción recomendados. Las diversas propiedades de los minerales al estar almacenada en Ontologías se pueden extraer mediante el uso del lenguaje de consultas semántico. Finalmente, dicho modelo Ontológico diseñado se puede usar en el futuro para la implementación de un portal construido con las herramientas de la Web Semántica, para que las búsquedas de propiedades de los minerales sean más rápidas y precisas.. Palabras clave.-Web Semántica, Ontologías, Reconocimiento de minerales . ABSTRACTThe present work is focused on the development of an Ontological model to help the recognition of sulfuric minerals. This ontology will be implemented following the recommended construction methods. The diverse properties of the minerals to be stored in Ontologies can be extracted by means of the semantic query language. Finally, this ontological model can be used in the future for the implementation of a portal built with Semantic Web tools, so that mineral property searches are faster and more accurate. Keywords.-Semantic Web, Ontologies, Mineral Recognition.
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Arribas, A. "Origen, transporte y deposición del uranio en los yacimientos en pizarras de la provincia de Salamanca." Estudios Geológicos 41, no. 5-6 (December 30, 1985): 301. http://dx.doi.org/10.3989/egeol.85415-6713.
Повний текст джерелаАнотація:
Las numerosas mineralizaciones de uranio existentes en el complejo esquisto grauváquico (CEG) de la Península Ibérica, pertenecientes a la paragénesis carbonatos, pechblenda (coifinita), adularia y sulfuros de Fe, tienen, además de una considerable importancia económica, un gran interés metalogénico, ya que su origen no ha podido ser explicado todavía de forma convincente. Así, desde 1959, estas mineralizaciones se han venido atribuyendo sucesivamente a una deposición del U en zonas fracturadas y brechificadas del basamento hercínico como consecuencia de uno de estos procesos: - magmáticos, por transporte del U en fluidos hidrotermales relacionados con la evolución y emplazamiento de los granitos hercínicos. - supergénicos, por liberación del U de los granitos durante los procesos de meteorización y erosión que dieron lugar a la penillanura pliocena. - de segregación, por lixiviación del U de las rocas plutónicas como consecuencia de movimientos tectónicos tardihercínicos y/o alpinos. - de difusión, por redistribución del U contenido en los metasedimentos fértiles del CEG por difusión térmica o flujo hidrotermal. En este trabajo, basándose en los estudios de campo y laboratorio llevados a cabo últimamente en min a FE, la más importante de las que existen en España de esta clase , se discuten las hipótesis anteriores y se exponen los principales caracteres metalogénicos del yacimiento. Entre éstos, los más significativos son: el alto contenido geoquímico en U, de 30 a 200 ppm, de las pizarras ampelíticas, que son predominantes en la zona; la naturaleza y los procesos de alteración, cloritización y hematización, de las rocas encajantes; la paragénesis de baja temperatura; las peculiares texturas geopetales de los minerales filonianos tardíos; la edad radiométrica de la pechblenda, 37 a 57 m. a.; el rango de temperatura y salinidad de las inclusiones fluidas de los carbonatos de la ganga, variable entre 230º y menos de 70ºC y 0 y 25% equiv. NaCl respectivamente; y el carácter superficial de los procesos tectónicos que dieron lugar a la fracturación hidráulica y a las brechas que contienen la mineralización. Finalmente, se compara ésta con la de otros yacimientos españoles y extranjeros, y se atribuye su origen a una reconcentración del U de las filitas ampelíticas como consecuencia del bombeo sísmico provocado en los materiales del CEG por los contragolpes de la orogenia alpina. De acuerdo con esta idea, las tensiones tangenciales que se desarrollaron en el basamento hercínico durante la primera mitad del Terciario habrían dado lugar a episódicas removilizaciones del U de los metasedimentos fértiles, el cual, al producirse el colapso de las zonas de dilatación, habría sido expulsado hacia la superficie por los fluidos hidrotermales de carácter geotérmico que depositaron el U y los minerales acompañantes en las brechas y fracturas asociadas con las fallas de desgarre.
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Vargas Cuervo, Roberto, and Jimmy Femández Lamus. "Evaluación geológica geoquímica y génesis de la zona de exclusión en Marmato Caldas–Colombia." Ingeniería y Región 4 (December 30, 2006): 8–19. http://dx.doi.org/10.25054/22161325.838.
Повний текст джерелаАнотація:
El histórico y conocido Distrito Minero de Marmato el cual ha sido explotado exhaustivamente desde tiempos Precolombinos. Se encuentra localizado dentro de la unidad Geomorfológica Cauca Patia y su posición geográfica esta bajo la influencia del sistema de fallas del Cauca. Condirección N-S predominatemente, la cual hace parte del sistema de fallas de Romeral afectando el pie de monte de la cordillera occidental. El área hace parte del terreno Cauca - Romeral presentándose una diversidad de rocas en compos ción y origen.En el yacimiento aurífero de Marmato dentro de la Zona de Exclusión la roca receptora de la mineralización Corresponde a la unidad litológica del porfido Dacítico (Nad) controlada por una combinación de fallas y fracturas y relleno de venas principalmente de sulfuros. Las zonas mineralizadas están asociadas a fallas distensivas y relleno de fracturas con diseminaciones vetiformes a través de las rocas. En forma de estovercas y su variación en el rumbo se debe a efectos tectónicos post-mineralización.La depositación de los minerales de mena y ganga en la zona de Marmato ocurre en tres fases las cuales identifican un mineral predominante así: Etapa temprana con pirita (Pyl), intermedia con esfalerita y la tardía con pirita (Py2) y carbonatos. La mineralización económica de este distrito (Au-Ag) se ha concentrado por lo general en las asociaciones paragenéticas tempranas y tardías.La alteración hidrotermal en la Zona de Exclusión corresponde a la alteración fílica a sericitica que es la que más predomina en el área de estudio y es producida por la alteración de plagioclasas y ferromagnesianos y domina en principalmente hacia el nivel inferior y se encuentra restringida a distancias no mayores de 2 metros de las zonas mineralizadas. La alteración propílica es caracterizada por la presencia de epidota y/o clorita. Comúnmente se presentan también albita. calcita y pirita. De acuerdo a las características metalogenicas geoquímicas. De la alteración hidrotermal y sus asociaciones mineral es el yacimiento de la Zona de Exclusión de Marmato se ubica dentro de los llamados depósitos epitermales de intermedia sulfuración.
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Li, Cun Xiong, Chang Wei, Hong Sheng Xu, Ji Qiang Liao, Zhi Gan Deng, and Gang Fan. "Leaching Behaviour of Metals from a Sphalerite Concentrate in Sulfuric Acid-Oxygen System." Advanced Materials Research 201-203 (February 2011): 1725–31. http://dx.doi.org/10.4028/www.scientific.net/amr.201-203.1725.
Повний текст джерелаАнотація:
Leaching behaviors of zinc, copper, indium and iron from a sphalerite concentrate in sulfuric acid-oxygen system has been investigated in the present paper. Various parameters were studied including particle size, concentration of sulfuric acid, partial pressure of oxygen, leaching temperature, and leaching time. The experimental data indicated that under the typical plant conditions employed up to 99% zinc , 85% copper and 90% indium extraction were achieved. The mineralogical analysis of the residue showed that the main minerals are elemental sulphur, unreacted pyrite and quartz, the amount of sulphide sulphur oxidized to sulfur during leaching is 81%. This process provides an effective way for the extraction of zinc, copper and indium from sphalerite concentrate.
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Jahromi and Ghahreman. "Effect of Surface Modification with Different Acids on the Functional Groups of AF 5 Catalyst and Its Catalytic Effect on the Atmospheric Leaching of Enargite." Colloids and Interfaces 3, no. 2 (April 17, 2019): 45. http://dx.doi.org/10.3390/colloids3020045.
Повний текст джерелаАнотація:
Carbon-based catalysts can assist the oxidative leaching of sulfide minerals. Recently, we presented that AF 5 Lewatit® is among the catalysts with superior enargite oxidation capacity and capability to collect elemental sulfur on its surface. Herein, the effect of acid pre-treatment of the AF 5 catalyst was studied on the AF 5 surface, to further enhance the catalytic properties of AF 5. The AF 5 catalyst was pretreated by hydrochloric acid, nitric acid and sulfuric acid. The results showed that the acid treatment drastically changes the surface properties of AF 5. For instance, the concentration of quinone-like functional groups, which are ascribed to the catalytic properties of AF 5, is 45.4% in the sulfuric acid pre-treatment AF 5 and only 29.8% in the hydrochloric acid-treated AF 5. Based on the C 1s X-ray photoelectron spectroscopy (XPS) results the oxygenated carbon is 30.6% in the sulfuric acid-treated AF 5, 29.2% in the nitric acid-treated AF 5 and 28.3% in the hydrochloric acid-treated AF 5. The nitric acid pre-treated AF 5 resulted in the highest copper recovery during the oxidative enargite leaching process, recovering 98.8% of the copper. The sulfuric acid-treated AF 5 recovered 97.1% of the enargite copper into the leach solution. Among different leaching media and pre-treatment the lowest copper recovery was achieved with the HCl pre-treated AF 5 which was 88.6%. The pre-treatment of AF 5 with acids also had modified its elemental sulfur adsorption capacity, where the sulfur adsorption on AF 5 was increased from 30.9% for the HCl treated AF 5 to 51.1% for the sulfuric acid-treated AF 5.
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Xiao, Junhui, Kai Zou, Wei Ding, Yang Peng, and Tao Chen. "Extraction of Lead and Zinc from a Rotary Kiln Oxidizing Roasting Cinder." Metals 10, no. 4 (April 2, 2020): 465. http://dx.doi.org/10.3390/met10040465.
Повний текст джерелаАнотація:
In this study, sulfuric acid leaching and gravity shaking-table separation by shaking a table are used to extract lead and zinc from a Pb-Zn oxidizing roasting cinder. The oxidizing roasting cinder—containing 16.9% Pb, 30.5% Zn, 10.3% Fe and 25.1% S—was obtained from a Pb-Zn sulfide ore in the Hanyuan area of China by a flotation-rotary kiln oxidizing roasting process. Anglesite and lead oxide were the main Pb-bearing minerals, while zinc sulfate, zinc oxide and zinc ferrite were the main Zn-bearing minerals. The results show that a part of lead contained in lead oxide is transformed to anglesite, and a 3PbO·PbSO4·H2O-dominated new lead mineral phase after acid leaching. A zinc leaching efficiency of 96.7% was obtained under the leaching conditions used: a leaching temperature of 55 °C; a leaching time of 90 min; a sulfuric acid dosage of 20%; a sulfurous acid dosage of 4%; a cinder particle size of <0.3 mm; and a solid-liquid ratio of R = 1:4. After the gravity shaking-table separation, a lead concentrate with 50.2% Pb, 2.33% Zn and lead recovery of 86.0% was produced. The main chemical compounds in leaching residue are anglesite, 3PbO·PbSO4·H2O, SiO2 and ZnFe2O4, while the main chemical compounds in lead concentrate are anglesite, 3PbO·PbSO4·H2O and SiO2.
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Nancucheo, Ivan, Guilherme Oliveira, Manoel Lopes, and David Johnson. "Bioreductive Dissolution as a Pretreatment for Recalcitrant Rare-Earth Phosphate Minerals Associated with Lateritic Ores." Minerals 9, no. 3 (February 26, 2019): 136. http://dx.doi.org/10.3390/min9030136.
Повний текст джерелаАнотація:
Recent research has demonstrated the applicability of a biotechnological approach for extracting base metals using acidophilic bacteria that catalyze the reductive dissolution of ferric iron oxides from oxidized ores, using elemental sulfur as an electron donor. In Brazil, lateritic deposits are frequently associated with phosphate minerals such as monazite, which is one of the most abundant rare-earth phosphate minerals. Given the fact that monazite is highly refractory, rare earth elements (REE) extraction is very difficult to achieve and conventionally involves digesting with concentrated sodium hydroxide and/or sulfuric acid at high temperatures; therefore, it has not been considered as a potential resource. This study aimed to determine the effect of the bioreductive dissolution of ferric iron minerals associated with monazite using Acidithiobacillus (A.) species in pH- and temperature-controlled stirred reactors. Under aerobic conditions, using A. thiooxidans at extremely low pH greatly enhanced the solubilization of iron from ferric iron minerals, as well that of phosphate (about 35%), which can be used as an indicator of the dissolution of monazite. The results from this study have demonstrated the potential of using bioreductive mineral dissolution, which can be applied as pretreatment to remove coverings of ferric iron minerals in a process analogous to the bio-oxidation of refractory golds and expand the range of minerals that could be processed using this approach.
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Naumov, K. D., K. A. Karimov, and A. M. Klyushnikov. "Complex Rare Earth Minerals Sulfate Decomposition Techniques Investigation." Materials Science Forum 946 (February 2019): 580–84. http://dx.doi.org/10.4028/www.scientific.net/msf.946.580.
Повний текст джерелаАнотація:
This article presents a study of Tomtor rare earth ore decomposition. This material contains a lot of valuable components such as REE and niobium (mas., %: 12,8 ΣREO (rare earth oxides), 0.039 Sc, 18.4 P2O5, 9.9 Fe, 9.0 Al, 0.24 ThO2, 8.2 Nb2O5). The study aims to find efficient ways of processing this deposit. Technologies using the sulfuric acid as the main reagent to leach are described in this article. Investigation has three trends. The first trend is agitation leaching at low sulfuric acid concentrations, temperatures up to 95 °C and atmospheric pressure. The second trend is pressure leaching at low sulfuric acid concentrations, high temperatures (up to 180 °C) and high pressure. The third trend is high temperature sulfatization with concentrated sulfuric acid at elevated temperature (up to 180 °C) and atmospheric pressure followed by aqueous leaching. The dependence of target components (rare earth elements, scandium, phosphorus) and the impurity (iron, aluminum, thorium) extractions into solution from major factors was studied.
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Jones, D. A., and A. J. P. Paul. "Galvanic Interactions between Alloys and Minerals in Sulfuric Acid." CORROSION 50, no. 7 (July 1994): 516–21. http://dx.doi.org/10.5006/1.3294352.
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Sokić, Marković, Stanković, Kamberović, Štrbac, Manojlović, and Petronijević. "Kinetics of Chalcopyrite Leaching by Hydrogen Peroxide in Sulfuric Acid." Metals 9, no. 11 (October 30, 2019): 1173. http://dx.doi.org/10.3390/met9111173.
Повний текст джерелаАнотація:
In ores, chalcopyrite is usually associated with other sulfide minerals, such as sphalerite, galena, and pyrite, in a dispersed form, with complex mineralogical structures. Concentrates obtained by flotation of such ores are unsuitable for pyrometallurgical processing owing to their poor quality and low metal recovery. This paper presents the leaching of chalcopyrite concentrate from the location “Rudnik, Serbia”. The samples from the flotation plant were treated with hydrogen peroxide in sulfuric acid. The influences of temperature, particle size, stirring speed, as well as the concentrations of hydrogen peroxide and sulfuric acid were followed and discussed. Hence, the main objective was to optimize the relevant conditions and to determine the reaction kinetics. It was remarked that the increase in temperature, hydrogen peroxide content, and sulfuric acid concentration, as well as the decrease in particle size and stirring speed, contribute to the dissolution of chalcopyrite. The dissolution kinetics follow a model controlled by diffusion, and the lixiviant diffusion controls the rate of reaction through the sulfur layer. Finally, the main characterization methods used to corroborate the obtained results were X-ray diffraction (XRD) as well as qualitative and quantitative light microscopy of the chalcopyrite concentrate samples and the leach residue.
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DARBANDI, MAHBOOBEH PARVARESH, and JAFAR TAHERI. "USING SULFUR-CONTAINING MINERALS IN MEDICINE: IRANIAN TRADITIONAL DOCUMENTS AND MODERN PHARMACEUTICAL TERMINOLOGY." Earth Sciences History 37, no. 1 (January 1, 2018): 25–33. http://dx.doi.org/10.17704/1944-6178-37.1.25.
Повний текст джерелаАнотація:
ABSTRACT Sulfur occurs naturally in the earth's crust as a pure element (native sulfur), as well as sulfide and sulfate minerals. From the biochemical point of view, sulfur is a vital element because it is a constituent of enzymes and other key proteins. In addition to modern uses of minerals, in old Iranian documents of traditional medicine, attention was paid to physico-chemical properties of minerals and the various methods of administration. In this review, the traditional usage of sulfur and sulfide minerals (e.g. orpiment, realgar and stibnite) and sulfate minerals (e.g. alum, jarosite, epsomite and melanterite) as documented in the Canon of Medicine of Avicenna (also known as Ibn Sina) and the Zakhireh Kharazmshahi of Jorjani, is compared with new findings about the advantages and disadvantages of these minerals in medical geology. The main conditions for the selection of mineral drugs was described first by Avicenna. There is a high correlation between old and modern pharmaceutical practices. The most important results concern the application of alum as a hemostatic agent (to inhibit hemorrhages), the use of jarosite as a method for treating osteoarthritis, the choice of melanterite for treating eczema, killing insects and as an anti-bacterial agent, the use of epsomite as an active ingredient in laxatives, homeostatics and mineral supplements, and the extensive use of sulfur in dermatology for its keratolytic effects and its supposed anti-microbial effects. In this review, newly developed pharmaceutical information about the use and effects on health of sulfide minerals will be compared to traditional pharmaceutical applications.
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Anzures, Brendan A., Stephen W. Parman, Ralph E. Milliken, Antonio Lanzirotti, and Matthew Newville. "XANES spectroscopy of sulfides stable under reducing conditions." American Mineralogist 105, no. 3 (March 1, 2020): 375–81. http://dx.doi.org/10.2138/am-2020-7146.
Повний текст джерелаАнотація:
Abstract X-ray absorption near-edge structure (XANES) spectroscopy is a powerful technique to quantitatively investigate sulfur speciation in geologically complex materials such as minerals, glasses, soils, organic compounds, industrial slags, and extraterrestrial materials. This technique allows non-destructive investigation of the coordination chemistry and oxidation state of sulfur species ranging from sulfide (2–oxidation state) to sulfate (6+ oxidation state). Each sulfur species has a unique spectral shape with a characteristic K-edge representing the s → p and d hybridization photoelectron transitions. As such, sulfur speciation is used to measure the oxidation state of samples by comparing the overall XANES spectra to that of reference compounds. Although many S XANES spectral standards exist for terrestrial applications under oxidized conditions, new sulfide standards are needed to investigate reduced (oxygen fugacity, fO2, below IW) silicate systems relevant for studies of extraterrestrial materials and systems. Sulfides found in certain meteorites (e.g., enstatite chondrites and aubrites) and predicted to exist on Mercury, such as CaS (oldhamite), MgS (niningerite), and FeCr2S4 (daubréelite), are stable at fO2 below IW-3 but rapidly oxidize to sulfate and/or produce sulfurous gases under terrestrial surface conditions. XANES spectra of these compounds collected to date have been of variable quality, possibly due to the unstable nature of certain sulfides under typical (e.g., oxidizing) laboratory conditions. A new set of compounds was prepared for this study and their XANES spectra are analyzed for comparison with potential extraterrestrial analogs. S K-edge XANES spectra were collected at Argonne National Lab for FeS (troilite), MnS (alabandite), CaS (oldhamite), MgS (niningerite), Ni1–xS, NiS2, CaSO4 (anhydrite), MgSO4, FeSO4, Fe2(SO4)3, FeCr2S4 (daubréelite), Na2S, Al2S3, Ni7S6, and Ni3S2; the latter five were analyzed for the first time using XANES. These standards expand upon the existing S XANES end-member libraries at a higher spectral resolution (0.25 eV steps) near the S K-edge. Processed spectra, those that have been normalized and “flattened,” are compared to quantify uncertainties due to data processing methods. Future investigations that require well-characterized sulfide standards, such as the ones presented here, may have important implications for understanding sulfur speciation in reduced silicate glasses and minerals with applications for the early Earth, Moon, Mercury, and enstatite chondrites.
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Xiao and Zhang. "Recovering Cobalt and Sulfur in Low Grade Cobalt-Bearing V–Ti Magnetite Tailings Using Flotation Process." Processes 7, no. 8 (August 14, 2019): 536. http://dx.doi.org/10.3390/pr7080536.
Повний текст джерелаАнотація:
There is 0.032% cobalt and 0.56% sulfur in the cobalt-bearing V–Ti tailings in the Panxi Region, with the metal sulfide minerals mainly including FeS2, Fe1−xS, Co3S4, and (Fe,Co)S2, and the gangue minerals mainly including aluminosilicate minerals. The flotation process was used to recover cobalt and sulfur in the cobalt-bearing V–Ti tailings. The results showed that an optimized cobalt–sulfur concentrate with a cobalt grade of 2.08%, sulfur content of 36.12%, sulfur recovery of 85.79%, and cobalt recovery and 84.77% were obtained by flotation process of one roughing, three sweeping, and three cleaning under roughing conditions, which employed pulp pH of 8, grinding fineness of < 0.074 mm occupying 80%, flotation concentration of 30%, and dosages of butyl xanthate, copper sulfate, and pine oil of 100 g/t, 30 g/t, and 20 g/t, respectively. Optimized one sweeping, two sweeping, and three sweeping conditions used a pulp pH of 9, and dosages of butyl xanthate, copper sulfate, and pine oil of 50 g/t, 15 g/t, 10 g/t; 25 g/t, 7.5 g/t, 5 g/t; 20 g/t, 5 g/t, 5 g/t, respectively. Optimized one cleaning, two cleaning, and three cleaning condition dosages of sodium silicate of 200 g/t, 100 g/t, 50 g/t, respectively. Study of analysis and characterization of cobalt–sulfur concentrate by X-ray diffraction (XRD), automatic mineral analyzer (MLA), scanning electron microscopy (SEM), and energy dispersive spectroscopy (EDS) showed that the main minerals in cobalt–sulfur concentrate are FeS2, Co3S4 and (Fe,Co)S2, of which FeS2 and (Fe,Co)S2 accounted for 65.64% and Co3S4 for 22.64%. Gangue minerals accounted for 11.72%. The element Co in (Fe,Co)S2 is closely related to pyrite in the form of isomorphism, and the flotability difference between cobalt and pyrite is very small, which makes it difficult to separate cobalt and sulfur. Cobalt–sulfur concentrate can be used as raw material for further separation of cobalt and sulfur in smelting by pyrometallurgical or hydrometallurgical methods.
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D'Angeli, Ilenia, Cristina Carbone, Maria Nagostinis, Mario Parise, Marco Vattano, Giuliana Madonia, and Jo De Waele. "New insights on secondary minerals from Italian sulfuric acid caves." International Journal of Speleology 47, no. 3 (September 2018): 271–91. http://dx.doi.org/10.5038/1827-806x.47.3.2175.
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Ou, Zhi Yuan, and Jin Hui Li. "A Novel Route for Copper Recovery from Waste Printed Circuit Boards via Mechanochemistry." Applied Mechanics and Materials 768 (June 2015): 569–75. http://dx.doi.org/10.4028/www.scientific.net/amm.768.569.
Повний текст джерелаАнотація:
This paper mainly introduces a novel route for copper recovery from waste printed circuit boards (WPCBs) via mechanochemistry. Copper in the crust is most commonly present as copper-iron-sulfide and copper-sulfide minerals (about 80%) and there exist many methods to extract copper from cooper ores in mineral engineering. It seems an alternative to transform the metallic components in obsolete materials to their corresponding compounds common in nature. By means of mechanochemistry, copper and sulfur were verified to form into copper sulfide in the model experiment, where, meanwhile, the optimal ball milling time was determined (20 minutes). In the real experiment, WPCB fragments and sulfur were mixed and ground for 20 minutes, no copper was detected by XRD analysis but copper sulfide was left. After leaching in sulfuric acid (3M) and hydrogen peroxide (30 wt%), the yield of copper reached nearly 95% and, also, resin was conserved for further utilization. This paper, for the first time, reports the green recovery route combining mechanical activation and sulfurization and may provide an alternative in other studies of metal recovery.
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Feng, Qi Cheng, Shu Ming Wen, Wen Juan Zhao, Ci Yun Chen, and He Fei Zhao. "Recovery of Molybdenum from Molybdenum Ore with a High Content of Carbon by Separating Carbon from Sulfur." Advanced Materials Research 634-638 (January 2013): 3450–53. http://dx.doi.org/10.4028/www.scientific.net/amr.634-638.3450.
Повний текст джерелаАнотація:
The study was aimed to recover molybdenum minerals from molybdenum ore with a high content of carbon by flotation process. The material belonged to a kind of refractory molybdenum ore from which molybdenum minerals could not be extracted effectively using traditional beneficiation and metallurgy, because of their similar floatability between carbon minerals and molybdenite and complex intergrowth. Based on the research on the properties of the material and lots of experiments, the carbon-molybdenum bulk flotation experiment was firstly carried out to concentrate molybdenum, and then some potassium permanganate and lime were added in carbon-molybdenum bulk flotation products to inhibit sulfide minerals along with appropriate air agitation. Under such a condition, the floatability of sulfide minerals was weakened and carbon was separated from sulfur. Then carbon concentrate and sulfur concentrate were used to extract molybdenum through metallurgy respectively.
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Ji, Ying, Kang Yang, Zhi Sun, and Wei Zhou. "The Depth Analysis of Different Form Sulfur in the Cement Minerals by Three-Step Extraction Method." Advanced Materials Research 524-527 (May 2012): 919–23. http://dx.doi.org/10.4028/www.scientific.net/amr.524-527.919.
Повний текст джерелаАнотація:
In order to investigate the different forms of sulfur in the cement, certain amount gypsum were blended into cement raw meal, which was pre-prepared by the cement plant. The above blends were firstly calcined to form cement clinker in a furnace at ~1450oC. Serious chemical solutions, such as, salicylic acid - methanol (SAM), potassium hydroxide - sucrose (KOSH) and acetic acid, were used to select the extractors from laboratory clinker. After the separation of silicate phase, iron aluminate phase, and intermediate phase of minerals, the trace amount minerals phase were enriched. Corresponding analytical methods, such as, XRD, XRF, SEM-EDS, were used to analyze the different sulfur type during the three-step extraction process. As a result, the trace sulfur minerals of cement was identified as three major forms of（KAl(SO4)2）,C4A3S, and（CaSO4）
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Luo, Lianchao, Huaguo Wen, Rongcai Zheng, Ran Liu, Yi Li, Xiaotong Luo, and Yaxian You. "Subaerial sulfate mineral formation related to acid aerosols at the Zhenzhu Spring, Tengchong, China." Mineralogical Magazine 83, no. 03 (January 14, 2019): 381–92. http://dx.doi.org/10.1180/mgm.2018.164.
Повний текст джерелаАнотація:
AbstractThe Zhenzhu Spring, located in the Tengchong volcanic field, Yunnan, China, is an acid hot spring with high SO42−concentrations and intense acid aerosol generation. In order to understand the formation mechanism of sulfate minerals at the Zhenzhu Spring and provide a better insight into the sulfur isotope geochemistry of the associated Rehai hydrothermal system, we investigated the spring water hydrochemistry, mineralogy and major-element geochemistry of sulfate minerals at the Zhenzhu Spring together with the sulfur-oxygen isotope geochemistry of sulfur-containing materials at the Rehai geothermal field and compared the isotope results with those in other steam-heated environments. Subaerial minerals include a wide variety of sulfate minerals (gypsum, alunogen, pickeringite, tamarugite, magnesiovoltaite and a minor Mg–S–O phase) and amorphous SiO2. The δ34S values of the subaerial sulfate minerals at the Zhenzhu Spring varied subtly from –0.33 to 1.88‰ and were almost consistent with the δ34S values of local H2S (–2.6 to 0.6‰) and dissolved SO42−(–0.2 to 5.8‰), while the δ18O values (–8.94 to 20.1‰) were between that of the spring waters (–10.19 to –6.7‰) and atmospheric O2(~23.88‰). The results suggest that most of the sulfate minerals are derived from the oxidation of H2S, similar to many sulfate minerals from modern steam-heated environments. However, the rapid environmental change (different ratio of atmospheric and water oxygen) at the Zhenzhu Spring accounts for the large variation of δ18O. The formation of subaerial sulfate minerals around the Zhenzhu Spring is related to acid aerosols (vapour and acid water droplets). The intense activity of spring water around vents supply the aerosol with H2SO4(H2S oxidation and acid water droplets formed by bubble bursting) and few cations. Deposition of the acid sulfate aerosol forms the acid condensate, which attacks the underlying rocks and releases many cations and anions to form subaerial sulfate minerals at the Zhenzhu Spring.
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TOMIOKA, Yuichi, Naoki HIROYOSHI, and Masami TSUNEKAWA. "Removal of Arsenic Ions in Sulfuric Acid Solutions by Sulfide Minerals." Shigen-to-Sozai 122, no. 6/7 (2006): 345–52. http://dx.doi.org/10.2473/shigentosozai.122.345.
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Sokic, Miroslav, Jovica Stojanovic, Branislav Markovic, Mladen Bugarcic, Nada Strbac, Zeljko Kamberovic, and Vaso Manojlovic. "Effects of structural and textural grain characteristics on leaching of sulphide minerals from a polymetallic concentrate by sodium nitrate and sulphuric acid solution." Chemical Industry 71, no. 6 (2017): 461–69. http://dx.doi.org/10.2298/hemind161130006s.
Повний текст джерелаАнотація:
In this paper, the influence of structural and textural characteristics of sulfide minerals on their leaching from a polymetallic concentrate by sulfuric acid and sodium nitrate solution is presented. The starting material was Pb?Zn?Cu sulphide polymetallic concentrate enriched during the flotation of a polymetallic ore in the "Rudnik" flotation plant (Rudnik ? Serbia). Leaching experiments were carried out in a closed glass reactor, which provides stable hermetic conditions and allows heating at constant temperature. Chemical, XRD, qualitative and quantitative microscopic and SEM/EDX analyses were used to characterizes samples of the polymetallic concentrate and leach residue. It was determined that chalcopyrite, sphalerite, galena, pyrrhotite and quartz were present in the polymetallic concentrate. The content of sulphide minerals was 69.5%, of which 60.9% occurred as liberated grains: 88.3% of chalcopyrite, 59.3% of sphalerite, 25.1% of galena and 51.6% of pirrhotite. The rest of chalcopyrite, sphalerite, galena and pirrhotite grains were in the forms of inclusions, impregnations, and simple and complex intergrowths. During the leaching process by sodium nitrate and sulphuric acid solution, it was shown previously that the leaching rate of sulphide minerals decreased with time while a part of the sulphide minerals remained in the leach residue. After leaching at 80?C for 120 min, the yields were 69.8, 82.7 and 67.1% for Cu, Zn and Fe, respectively. Lead, in the form of insoluble anglesite, remained in the leach residue. In addition to the anglesite, unleached sulfide minerals and quartz, elemental sulfur was found in the solid residue. The content of sulphide minerals was 35% of which 33.7% minerals occur independently. In specific, 54.7% of chalcopyrite, 31.9% of sphalerite, 8.2% of galena and 37.6% of pyrrhotite appear as separate grains with highly corroded surfaces. Therefore, the structural assembly of sulphide grains in the polymetallic concentrate is favourable and it is not the reason for the observed decrease in the leaching rate in the final process stages. The obtained findings may be explained by the presence of elemental sulphur that is formed during the reaction and precipitated at the grain surfaces, thus creating a diffusion barrier for the leach solution.
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Xiang, Xiao Jun, Yan Shuang, and Kui Gong. "Sulfur and Lead Isotopic Geochemistry of the Shidi Pb-Zn Deposit in Xiushan County, Chongqing." Advanced Materials Research 842 (November 2013): 180–86. http://dx.doi.org/10.4028/www.scientific.net/amr.842.180.
Повний текст джерелаАнотація:
The Shidi Pb-Zn deposit is located in Xiushan County, southern Chongqing, and its orebodies were hosted in marine carbonates of the Cambrian Pingjing Formation. The authors selected sulfide minerals from the deposit for the analysis of sulfur and lead isotopic compositions. Theδ34S values of sulfide minerals vary from 10.8 to 15.6, with an average value of 13.52, indicating these sulfide materials were mainly derived from marine sulfate reduction. The 206Pb/204Pb, 207Pb/204Pb and 208Pb/204Pb ratios for sulfide minerals vary within the ranges of 18.319~18.422, 15.740~15.784 and 38.355~38.511, respectively. In the diagrams of Zartman, the Pb isotopic compositions of sulfide minerals fall into the regional upper crust lead zone. According to the characteristics of sulfur and lead isotopic compositions of the Shidi Pb-Zn deposit, the ore-forming materials might have come from the black shales of the Lower Cmabrian Niutitang Formation.
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Elesin, Mikhail A., and Gennady I. Berdov. "HYDRATION STUDY OF PORTLAND CEMENT MINERALS IN LIMY-SULFUR TEMPERE." IZVESTIYA VYSSHIKH UCHEBNYKH ZAVEDENIY KHIMIYA KHIMICHESKAYA TEKHNOLOGIYA 59, no. 5 (July 12, 2018): 54. http://dx.doi.org/10.6060/tcct.20165905.5046.
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The interaction of minerals of the Portland cement (alit, belit, alyumoferrite) was studied with a limy-sulfur tempere. Higher SiO2 content in a liquid phase was established at hydration as well as hydration process acceleration. The strength of cement materials could be increased by 20-40% at application of such tempere with sulfur concentration of 180 g/l.
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Nugroho, R., H. Takanashi, M. Hirata, and T. Hano. "Denitrification of industrial wastewater with sulfur and limestone packed column." Water Science and Technology 46, no. 11-12 (December 1, 2002): 99–104. http://dx.doi.org/10.2166/wst.2002.0723.
Повний текст джерелаАнотація:
An autotrophic denitrification system was developed for nitrate contaminated industrial wastewater whose C/N ratio was very low. The microbes containing Thiobacillus denitrificans as a dominant species were attached on the surface of granular elemental sulfur packed in a column. Elemental sulfur was used as an electron donor for autotrophic denitrification. The granules of limestone were mixed with the granular sulfur to moderate the decrease of alkalinity during autotrophic denitrification. The stoichiometry and basic kinetics of denitrification were studied in column runs. The effects of minerals such as phosphorus on treatment performance were clarified. The wastewater from steel production plants was treated by the present biofilm process. Low extent of nitrogen removal was caused by the lack of minerals.
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Fitriyani, Nur Lu'lu, Agus Irianto, and Hendro Pramono. "Potential of Chemolitotrophic Bacteria From Gold Mining Area in Sulfur Oxidation Process." Biosaintifika: Journal of Biology & Biology Education 10, no. 3 (December 19, 2018): 526–32. http://dx.doi.org/10.15294/biosaintifika.v10i3.12544.
Повний текст джерелаАнотація:
Gold in nature is covered by rocks which contain sulfide minerals such as pyrite, chalcopyrite, arsenopyrite, and others sulfide minerals. Chemolithotrophic bacteria have the ability to oxidize the sulfur compounds and can be used in the process of releasing gold from carrier rocks which contain sulfide minerals. This research aimed to explore and identify the chemolithotrophic bacteria from gold mining areas as well as determine their potential for sulfur oxidation. The methods used in this study were exploring the potential of bacteria in sulfur oxidation and describing the variety of bacteria that were isolated from gold mining areas by 16s rRNA identification. The results showed that there were six isolates from isolation with Starkey solid medium, i.e. Bl-1, B1-2, B1-3, B1-4, B1-5 and B1-6 that were similar to Paenibacillus sp., Enterobacter ludwigiis train E8-13, uncultured Burkholderia sp., Uncultured bacterium clone N4.5, Bacillus subtilis strain CICC 10023, and Bacterium enrichment culture clone 02 respectively. The B1-3 isolate showed the highest increase of sulfate compound in the medium (8.04 % at 649.55 ppm). This indigenous bacteria will be able to be used to release gold from rock which contains sulfide minerals and reduce the use of hazardous chemicals commonly used in gold mining.
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Xiao, Junhui, and Yushu Zhang. "Extraction of Cobalt and Iron from Refractory Co-Bearing Sulfur Concentrate." Processes 8, no. 2 (February 6, 2020): 200. http://dx.doi.org/10.3390/pr8020200.
Повний текст джерелаАнотація:
In this study, oxidizing roasting, segregation roasting, and magnetic separation are used to extract cobalt and iron from refractory Co-bearing sulfur concentrate. The Co-bearing sulfur concentrate containing 0.68% Co, 33.26% Fe, and 36.58% S was obtained from V-Ti magnetite in the Panxi area of China by flotation. Cobalt pyrite and linneite were the Co-bearing minerals, and the gangue minerals were mica, chlorite, feldspar, and calcite in Co-bearing sulfur concentrate. The results show that cobalt is transformed from Co-pyrite and linneite to a Co2FeO4-dominated new cobalt mineral phase, and iron is transformed from pyrite to Fe2O3 and an Fe3O4-dominated new iron mineral phase after oxidizing roasting. Cobalt changed from CoFe2O4 to a new cobalt mineral phase dominated by [Co] Fe solid solution, and iron changed from Fe2O3 to a new iron mineral phase dominated by metal Fe and Fe3O4 after segregation roasting. Cobalt concentrate with a cobalt grade of 15.15%, iron content of 71.22%, and cobalt recovery of 90.81% as well as iron concentrate with iron grade of 60.06%, cobalt content of 0.11%, and iron recovery of 76.23% are obtained. The main minerals in the cobalt concentrate are Fe, [Co]Fe, Fe3O4, and SiO2, and the main minerals in the iron concentrate are Fe3O4, FeO, Ca2Si2O4, and Ca2Al2O4.
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Sokić, Miroslav, Slobodan Radosavljević, Branislav Marković, Vladislav Matković, Nada Štrbac, Željko Kamberović, and Dragana Živković. "Influence of chalcopyrite structure on their leaching by sodium nitrate in sulphuric acid." Metallurgical and Materials Engineering 20, no. 1 (March 31, 2014): 53–60. http://dx.doi.org/10.5937/metmateng1401053s.
Повний текст джерелаАнотація:
During the chalcopyrite leaching by sodium nitrate and sulfuric acid solution, leaching rate decreases with increasing the time and a part of chalcopyrite mineral grains remains in the leach residue. In chalcopyrite concentrate, 95.5 % of chalcopyrite mineral occurs as in liberated grains, and the rest is in association with gangue minerals, which is very favorably from the aspect of hydrometallurgical treatment. Complex forms, like impregnations and complex intergrowths, do not exist. After experiments carried out, leaching of copper achieved 84 % at temperature 80 o C and time 240 min. In the all leach residues, 97 % chalcopyrite mineral grains occur as liberated with highly corroded surfaces. Therefore, the structural assembly of chalcopyrite grains is favorable and no reason to reduce the leaching rate in the final stage of reaction. Reason for this is elemental sulfur, which was formed during the reaction, precipitated at the particle surfaces, and slowed down the leaching rate in the final stage of leaching process.
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Liu, Guiqing, Kaixi Jiang, Bangsheng Zhang, Zhonglin Dong, Fan Zhang, Fang Wang, Tao Jiang, and Bin Xu. "Selective Flotation of Elemental Sulfur from Pressure Acid Leaching Residue of Zinc Sulfide." Minerals 11, no. 1 (January 18, 2021): 89. http://dx.doi.org/10.3390/min11010089.
Повний текст джерелаАнотація:
An efficient flotation process was developed to selectively recover elemental sulfur from a high-sulfur pressure acid leaching residue of zinc sulfide concentrate. The process mineralogy analysis showed that the sulfur content reached 46.21%, and 81.97% of the sulfur existed as elemental sulfur which was the major mineral in the residue and primarily existed as pellet aggregate and biconical euhedral crystal. An elemental sulfur concentrate product with 99.9% of recovery and 83.46% of purity was obtained using the flotation process of one-time blank rougher, two-time agent-added roughers, and two-time cleaners with Z-200 as collector and Na2S + ZnSO4 + Na2SO3 as depressant. The flotation experiment using return water indicated that the cycle use of return water had no adverse effect on the flotation performance of elemental sulfur. The process mineralogy analysis manifested that main minerals in the residue directionally went into the flotation products. Most of elemental sulfur entered the concentrate while other minerals almost completely went into the tailing. Main valuable elements lead, zinc, and silver entered the tailing with sulfides and could be recovered by lead smelting. The proposed process can realize the comprehensive recovery of valuable components in the high-sulfur residue and thus it has wide industrial application prospect.
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Tan, Xin, Wei Guo Wu, Zhong Ming Wang, Xin Tan, and Hai Ying Liu. "Experimental Study on Comprehensive Recovery of Valuable Minerals from Flotation Tailings in Copper-Molybdenum Mine." Advanced Materials Research 878 (January 2014): 234–43. http://dx.doi.org/10.4028/www.scientific.net/amr.878.234.
Повний текст джерелаАнотація:
In this paper, the mineral processing experimental study on the flotation tailings which are stored in the tailings pond of a copper-molybdenum mine is conducted, with a large content of slimes and kaolinite in the tailings and the fine particle sizes and poor locked particles of most of valuable minerals disseminated in the gangue minerals taken into consideration. Based on the mineralogical characteristics of the ore, a combined process is adopted in order to recover copper, molybdenum, sulfur and iron minerals from the ore, this process contains a series of steps in a particular sequence, which are pre-desliming of the ore, bulk flotation of copper and molybdenum of the coarse fraction, separation of Cu-Mo, separating sulfur from bulk flotation tailings and low-intensity magnetic separation of iron from sulfur flotation tailings. The results of the closed circuit test show that it can be obtained copper concentrate with a Cu grade of 20.61% and a recovery rate of 28.52%, molybdenum concentrate with a Mo grade of 36.00% (containing 20% C) and a recovery rate of 43.35%, sulfur concentrate with a S grade of 35.66% and a recovery rate of 42.58%, and iron concentrate with a Fe grade of 68.40% and a recovery rate of 6.85% (75% of phase recovery of magnetite).
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Feijoo, Patricio, Esteban Bustamante, and Christian Guillén. "Curvas granulométricas como alternativa para la caracterización del material rocoso en minería." Athenea 2, no. 3 (March 7, 2021): 28–39. http://dx.doi.org/10.47460/athenea.v2i3.14.
Повний текст джерелаАнотація:
En proyectos mineros es importante determinar ciertos parámetros, como la resistencia a compresión simple (RCS) del material rocoso, ya que es fundamental para el uso de clasificaciones geomecánicas, como RMR o Índice Q, las que establecen geometrías para estabilidad en canteras y fortificación en minas subterráneas, evitando desprendimientos de rocas o derrumbes, garantizando la salud de trabajadores y protección de equipos. Pero, para conocer la RCS, es necesario enviar muestras al laboratorio, lo cual hace tediosa y costosa su valoración. Este trabajo introduce una propuesta para la determinación de este parámetro, mediante una sucesión simple y sencilla de procesos mecánicos. Obtenidas muestras de roca, prepararlas, triturarlas, clasificarlas y valorada su RCS, se establece una relación entre estos parámetros, evitando enviar permanentemente muestras al laboratorio. Esta relación se presenta de una manera gráfica, de fácil interpretación y propone una ecuación, para de esta forma obtener el parámetro de una manera aproximada.
Palabra Claves: Minería, trituración de rocas, curvas granulométricas, resistencia a la compresión uniaxial.
Referencias
[1]E. P. Feijoo Calle y J. C. Padrón Suarez, «LA RESISTIVIDAD DE ROCAS Y SU RELACIÓN CON LA RESISTENCIA A COMPRESIÓN SIMPLE EN MINA», uct, vol. 24, n.º 99, pp. 61-67, abr. 2020.
[2]E. P. Feijoo Calle, C. A. Flores Vera y B. A. Feijoo Guevara, "El concepto del área granulométrica y su relación con la resistencia a la compresión simple de rocas", 2019 VII Congreso Internacional de Ingeniería, Ciencias y Tecnología (IESTEC) , Panamá, 2019, págs. 52-56, doi: 10.1109/ IESTEC46403.2019.00018.
[3]F. Escolano, A. Mazariegos, Guía de reconocimiento de rocas en Ingeniería Civil. España: Editorial Garceta, Escuela Técnica Superior de Ingeniería Civil, Universidad Politécnica de Madrid, 2014.
[4]E. P. Feijoo Calle y D. M. Román Celi, «CORRELACIÓN ENTRE LA DEFORMACIÓN Y LA RESISTENCIA A LA COMPRESIÓN EN ROCAS», uct, vol. 23, n.º 91, p. 6, may. 2019.
[5]L. González de Vallejo, M. Ferrer, L. Ortuño, C. Oteo, Ingeniería Geológica. España: 2004.
[6]E. P. Feijoo Calle y D. C. Iñiguez Toral, «CORTE EN ROCAS Y SU RELACIÓN CON LA RESISTENCIA A COMPRESIÓN SIMPLE». RISTI, N.o E 30, 59-67, jun. 2020.
[7]M. Galván, Mecánica de Rocas. Correlación entre la Resistencia a Carga Puntual y la Resistencia a la Compresión Simple. Colombia: Universidad del Valle, Cali, 2015.
[8]J. Alonso, J. Gómez, J. Herbert, Perforación y voladura de rocas en minería. España: Universidad Politécnica de Madrid, 2013.
[9]L. Murcia, "Procedimiento para el diseño de mallas de voladura en explotación de canteras a cielo abierto con base en la estabilidad temporal y final de los bancos de producción". Tesis de Grado, Pontificia Universidad Javeriana, Bogotá, Colombia, 2016.
[10]F. G. Blyth, M. H. de Freitas, Geología para Ingenieros. México: Cecsa, 2003.
[11]F. Arévalo, I. Cano, "Influencia de la instalación de una chancadora y faja transportadora en el incremento de producción del área de molienda de óxido de calcio Puylucana, Cajamarca". Tesis de Grado, Universidad Privada del Norte, Cajamarca, Perú, 2018.
[12]M. Colquehuanca, "Implementación de mejora al sistema de una planta de trituración de roca, para optimizar el rendimiento en el proceso de producción de agregados". Tesis de Grado, Universidad Privada del Norte, Lima, Perú, 2018.
[13]R. Calabuig, "Efecto de la adición de cal en las propiedades mecánicas y durabilidad de hormigones con altos contenidos en cenizas volantes silíceas". Tesis profesional, Piura, Universidad Nacional de Piura, Perú, 2015.
[14]D. Olguín, "Proceso de Producción de Agregados Pétreos y su Control de Calidad". Tesis de Grado, Universidad Autónoma de México, México D. F., México, 2016.
[15]C. Lara, H. Cuestas, "Determinación del wok index según la teoría de E. Bond mediante pruebas de moliendabilidad de sulfuros para el control de la etapa de molienda a nivel de laboratorio en la Facultad de Ingeniería Química U.N.C.P. Universidad Nacional del Centro del Perú". Tesis de grado, Huancayo, Perú, 2012.[16]A. Maistri, Guía al Curso de Tratamiento de Minerales y a las Prácticas de Laboratorio.Universidad del Azuay. Ecuador: Universidad del Azuay, 1993.
[17]J. Toirac, Caracterización Granulométrica de las Plantas productoras de arena en la República Dominicana. República Dominicana, Ciencia y Sociedad, 2012.
[18]Feijoo P., Brito E., "Caracterización de la roca mediante propiedades físicas y su relación con la Resistencia a la Compresión Simple", 2020 I Congreso Internacional de Ciencia y Tecnología Morona Santiago (CICTMS), Escuela Superior Politécnica del Chimborazo, Ecuador.
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Cifuentes, Gabriel Ricardo, Juan Jiménez-Millán, Claudia Patricia Quevedo, and Rosario Jiménez-Espinosa. "Transformation of S-Bearing Minerals in Organic Matter-Rich Sediments from a Saline Lake with Hydrothermal Inputs." Minerals 10, no. 6 (June 9, 2020): 525. http://dx.doi.org/10.3390/min10060525.
Повний текст джерелаАнотація:
Geothermal systems can provide significant amounts of hydrothermal sulfur to surface waters, increasing salinity and avoiding some of the common anthropic uses. The objective of this study was to investigate the sedimentary neoformation of S-bearing phases in organic matter-rich sediments from a saline lake with hydrothermal inputs (Sochagota Lake, Colombia). Detrital kaolinite and quartz are the main minerals of the materials deposited in the Sochagota Lake. Neoformed clay minerals (illite and illite-dioctahedral vermiculite mixed layers) are concentrated in the central and northern part of the lake in sediments with high organic matter content. The most organic matter-rich materials are characterized by S-bearing minerals: mackinawite, pyrite, and elemental sulfur (S°). FESEM, high-resolution transmission electron microscopy (HRTEM), EDS, and Raman microspectrometry have revealed the presence of cell-shape aggregates of mackinawite nanoparticles filling the inner part of plant fragments, indicating that microorganisms were involved in the hydrothermal sulfur uptake. The alteration of mackinawite in free sulfide excess environment produced the formation of framboidal pyrite. The evolution to conditions with the presence of oxygen favored the formation of complex S° morphologies.
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IONESCU, Lavinel G., Paulo Cesar Pereira DAS NEVES, and Dareson Vieira de Freitas DE FREITAS. "MINERALOGICAL ASPECTS OF ARSENIC -THE ARSENATE MINERALS." SOUTHERN BRAZILIAN JOURNAL OF CHEMISTRY 19, no. 19 (December 20, 2011): 85–106. http://dx.doi.org/10.48141/sbjchem.v19.n19.2011.87_2011.pdf.
Повний текст джерелаАнотація:
Arsenic is an element known since ancient times. It is the 52nd element in order of chemical abundance in the Earth s crust with 1.8 ppm (grams per metric ton). Arsenic combines relatively easily with chlorine sulfur, oxygen, and many metals. This article describes some of the uses and properties of arsenic and arsenic compounds and presents a synopsis of the two hundred and seventy-eight (278) arsenate minerals known at the present time.
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Stopić, Srećko, and Bernd Friedrich. "Leaching of rare earth elements with sulfuric acid from bastnasite ores." Vojnotehnicki glasnik 66, no. 4 (2018): 757–70. http://dx.doi.org/10.5937/vojtehg66-17177.
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Lal, Swapnil, Zhaoyu Zheng, Julius Pavlov, and Athula B. Attygalle. "Brimstone chemistry under laser light assists mass spectrometric detection and imaging the distribution of arsenic in minerals." Dalton Transactions 47, no. 25 (2018): 8221–28. http://dx.doi.org/10.1039/c8dt01042k.
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Abbott, Andrew P., Ahmed Z. M. Al-Bassam, Alex Goddard, Robert C. Harris, Gawen R. T. Jenkin, Frazer J. Nisbet, and Matthias Wieland. "Dissolution of pyrite and other Fe–S–As minerals using deep eutectic solvents." Green Chemistry 19, no. 9 (2017): 2225–33. http://dx.doi.org/10.1039/c7gc00334j.
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García-Meza, J. V., R. H. Lara, and H. R. Navarro-Contreras. "Application of Raman Spectroscopy to the Biooxidation Analysis of Sulfide Minerals." International Journal of Spectroscopy 2012 (February 20, 2012): 1–7. http://dx.doi.org/10.1155/2012/501706.
Повний текст джерелаАнотація:
We report the application of confocal laser scanning microscopy CLSM and Raman spectroscopy on the (bio)chemical oxidation of pyrite and chalcopyrite, in order to understand how surface sulfur species () affects biofilm evolution during mineral colonization by Acidithiobacillus thiooxidans. We found that cells attachment occurs as cells clusters and monolayered biofilms within the first 12 h. Longer times resulted in the formation of micro- and macrocolonies with variable cell density and higher epifluorescence signal of the extracellular polymeric substances (EPS), indicating double dynamic activity of A. thiooxidans: sulfur biooxidation and biofilm formation. Raman spectra indicated consumption modification during biofilm evolution. Hence, cell density increase was primarily associated with the presence of ; the presence of refractory sulfur species on the mineral surfaces does not to affect biofilm evolution. The EPS of the biofilms was mainly composed of extracellular hydrophobic compounds (vr. gr. lipids) and a minor content of hydrophilic exopolysaccharides, suggesting a hydrophobic interaction between attached cells and the altered pyrite and chalcopyrite.
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Callegaro, Sara, Kalotina Geraki, Andrea Marzoli, Angelo De Min, Victoria Maneta, and Don R. Baker. "The quintet completed: The partitioning of sulfur between nominally volatile-free minerals and silicate melts." American Mineralogist 105, no. 5 (May 1, 2020): 697–707. http://dx.doi.org/10.2138/am-2020-7188.
Повний текст джерелаАнотація:
Abstract Magmatic systems are dominated by five volatiles, namely H2O, CO2, F, Cl, and S (the igneous quintet). Multiple studies have measured partitioning of four out of these five volatiles (H2O, CO2, F, and Cl) between nominally volatile-free minerals and melts, whereas the partitioning of sulfur is poorly known. To better constrain the behavior of sulfur in igneous systems we measured the partitioning of sulfur between clinopyroxene and silicate melts over a range of pressure, temperature, and melt composition from 0.8 to 1.2 GPa, 1000 to 1240 °C, and 49 to 66 wt% SiO2 (13 measurements). Additionally, we determined the crystal-melt partitioning of sulfur for plagioclase (6 measurements), orthopyroxene (2 measurements), amphibole (2 measurements), and olivine (1 measurement) in some of these same run products. Experiments were performed at high and low oxygen fugacities, where sulfur in the melt is expected to be dominantly present as an S6+ or an S2– species, respectively. When the partition coefficient is calculated as the total sulfur in the crystal divided by the total sulfur in the melt, the partition coefficient varies from 0.017 to 0.075 for clinopyroxene, from 0.036 to 0.229 for plagioclase, and is a maximum of 0.001 for olivine and of 0.003 for orthopyroxene. The variation in the total sulfur partition coefficient positively correlates with cation-oxygen bond lengths in the crystals; the measured partition coefficients increase in the order: olivine < orthopyroxene < clinopyroxene ≤ amphibole and plagioclase. At high oxygen fugacities in hydrous experiments, the clinopyroxene/melt partition coefficients for total sulfur are only approximately one-third of those measured in low oxygen fugacity, anhydrous experiments. However when the partition coefficient is calculated as total sulfur in the crystal divided by S2– in the melt, the clinopyroxene/melt partition coefficients for experiments with melts between ~51 and 66 wt% SiO2 can be described by a single mean value of 0.063 ± 0.010 (1σ standard deviation about the mean). These two observations support the hypothesis that sulfur, as S2–, replaces oxygen in the crystal structure. The results of hydrous experiments at low oxygen fugacity and anhydrous experiments at high oxygen fugacity suggest that oxygen fugacity has a greater effect on sulfur partitioning than water. Although the total sulfur clinopyroxene-melt partition coefficients are affected by the Mg/(Mg+Fe) ratio of the crystal, partition coefficients calculated using S2– in the melt display no clear dependence upon the Mg# of the clinopyroxene. Both the bulk and the S 2– partition coefficients appear unaffected by IVAl in the clinopyroxene structure. No effect of anorthite content nor of iron concentration in the crystal was seen in the data for plagioclase-melt partitioning. The data obtained for orthopyroxene and olivine were too few to establish any trends. The partition coefficients of total sulfur and S 2– between the crystals studied and silicate melts are typically lower than those of fluorine, higher than those of carbon, and similar to those of chlorine and hydrogen. These sulfur partition coefficients can be combined with analyses of volatiles in nominally volatile-free minerals and previously published partition coefficients of H2O, C, F, and Cl to constrain the concentration of the igneous quintet, the five major volatiles in magmatic systems.
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Safarzadeh, M. Sadegh, Jinshan Li, Michael S. Moats, and Jan D. Miller. "The stability of selected sulfide minerals in sulfuric acid and acidic thiocyanate solutions." Electrochimica Acta 78 (September 2012): 133–38. http://dx.doi.org/10.1016/j.electacta.2012.05.117.
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Xie, Xian, Zi Xuan Yang, Xiong Tong, and Ji Yong Li. "Research on Exploration of Mineral Processing for a Iron Ore." Advanced Materials Research 1094 (March 2015): 397–400. http://dx.doi.org/10.4028/www.scientific.net/amr.1094.397.
Повний текст джерелаАнотація:
Iron ore minerals are mainly silicate-type iron minerals in raw ore, and its distribution rate was 51.93%; followed by magnetic iron, and its distribution rate was 36.81%; content and distribution rate of other minerals was very low; element grade of iron, phosphorus, sulfur, silica were 11.90%, 0.043%, 0.013% and 45.23%, the main gangue were silica and calcium oxide, recyclable iron minerals mainly is magnetic iron mineral. Due to the grade of iron of raw ore and the amounts of optional magnetite was relatively little, in order to investigate the optional of low-grade ore, weak magnetic separation test and weak magnetic separation tailings-strong magnetic separation test were put into effect.
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HAUCK, J., and K. MIKA. "CRYSTAL HABIT OF MINERALS — A CRYSTAL CHEMICAL APPROACH." International Journal of Modern Physics B 21, no. 06 (March 10, 2007): 871–83. http://dx.doi.org/10.1142/s0217979207036734.
Повний текст джерелаАнотація:
Homogeneous particles A like carbon atoms in diamond, CO 3 ions in CaCO 3, or sulfur molecules in sulfur with different A–A interactions are ordered in such a way that the bulk structure can be characterized by the self-coordination numbers T i, i = 1-3, of nearest, second, and third neighbors. There are about 500 sets with increased Ti values and about 500 sets with reduced Ti values, which can be obtained from characteristic lattice complexes. The different sets with increased Ti values are characterized by S, L, or R for sphere, layer, or rod packing. Two or more particles A, B, C, etc., can belong to the same set like Na and Cl atoms in NaCl or different sets like Ca and F atoms in CaF 2. The Dirichlet domains of A and B ( CaF 2) or A + B ( NaCl ) are approaches to the morphological lattices (cubes or rhombododecahedra). Planes with a high density of A positions and thus low h k l values like the {111} planes of octahedra are derived from Bravais' theory. The morphological lattices of layer or rod packings are layers or rods because of the increased densities of A in layers or rods.