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Julian C Baker - One of the best experts on this subject based on the ideXlab platform.
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early diagenetic Siderite as an indicator of depositional environment in the triassic rewan group southern bowen basin eastern australia
Sedimentology, 1996Co-Authors: J Kassan, Julian C Baker, Joe P HamiltonAbstract:Early concretionary and non-concretionary Siderites are common in subsurface Triassic sandstones and mudrocks of the Rewan Group, southern Bowen Basin. A detailed petrological and stable isotopic study was carried out on these Siderites in order to provide information on the depositional environment of the host rocks. The Siderites are extremely pure, containing 85–97 mol% FeCO3, and are commonly enriched in manganese. δ13C (PDB) values are highly variable, ranging from - 18·4 to +2·9‰, whereas δ18O (PDB) values are very consistent, ranging from - 14·0 to - 10·2‰ (mean= - 11·9 ± 1·0‰). The elemental and oxygen isotopic composition of the Siderites indicates that only meteoric porewaters were involved in Siderite formation, implying that host rocks accumulated in totally non-marine environments. The carbon isotopic composition of the Siderites is interpreted to reflect mixing of bicarbonate/carbon dioxide generated by methane oxidation and methanogenesis. Very low δ13C values demonstrate that, contrary to current views, highly 13C-depleted Siderite can be produced at shallow burial depths in anoxic non-marine sediments.
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Sandstone Diagenesis: Recent and Ancient - Early diagenetic Siderite as an indicator of depositional environment in the Triassic Rewan Group, southern Bowen Basin, eastern Australia
Sedimentology, 1996Co-Authors: Julian C Baker, J Kassan, P. Joe HamiltonAbstract:Early concretionary and non-concretionary Siderites are common in subsurface Triassic sandstones and mudrocks of the Rewan Group, southern Bowen Basin. A detailed petrological and stable isotopic study was carried out on these Siderites in order to provide information on the depositional environment of the host rocks. The Siderites are extremely pure, containing 85–97 mol% FeCO3, and are commonly enriched in manganese. δ13C (PDB) values are highly variable, ranging from - 18·4 to +2·9‰, whereas δ18O (PDB) values are very consistent, ranging from - 14·0 to - 10·2‰ (mean= - 11·9 ± 1·0‰). The elemental and oxygen isotopic composition of the Siderites indicates that only meteoric porewaters were involved in Siderite formation, implying that host rocks accumulated in totally non-marine environments. The carbon isotopic composition of the Siderites is interpreted to reflect mixing of bicarbonate/carbon dioxide generated by methane oxidation and methanogenesis. Very low δ13C values demonstrate that, contrary to current views, highly 13C-depleted Siderite can be produced at shallow burial depths in anoxic non-marine sediments.
Zhitao Yuan - One of the best experts on this subject based on the ideXlab platform.
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regulating effects of citric acid and pregelatinized starch on selective flocculation flotation of micro fine Siderite
Journal of Molecular Liquids, 2020Co-Authors: Li-xia Li, Zhitao Yuan, Chunfeng LiAbstract:Abstract To improve the beneficiation efficiency of carbonate-bearing iron ore, a selective-flocculation flotation method was developed to separate micro-fine Siderite with citric acid and pregelatinized starch, which serve as the dispersant and the flocculant, respectively. Given that pregelatinized starch may have adverse effects on dispersion effect of citric acid, the regulating effects of these two species on the selective flocculation flotation of micro-fine Siderite were examined by micro-flotation of artificially mixed ores and molecular dynamics simulations. The analyses of particle-size distribution and aggregation behaviour showed that citric acid effectively decreased the attachment of micro-fine Siderite to hematite and quartz. In contrast, micro-fine Siderite formed flocs selectively with pregelatinized starch. Molecular dynamics calculations revealed that citric acid and pregelatinized starch could co-adsorb on Siderite. Collector molecules of sodium oleate penetrated the adsorption layer and thus were adsorbed onto Siderite. However, sodium oleate was unable to penetrate the dense pregelatinized starch layer on hematite. Furthermore, both pregelatinized starch and sodium oleate were barely adsorbed onto quartz. The regulating effects of citric acid and pregelatinized starch improved the selective flocculation flotation of micro-fine Siderite. The FeO content of the ore was 5.15%, and this was increased to 20.15% by the above treatment, with a recovery rate of 71.08%.
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Mechanical properties of Siderite and hematite from DFT calculation
Minerals Engineering, 2020Co-Authors: Chen Zhang, Zhitao Yuan, Zhenguo Song, Yi Ran ZhangAbstract:Abstract Aiming to reveal the easy-sliming mechanism of Siderite in the grinding process of carbonate-bearing iron ores, mechanical properties of Siderite and hematite were computed by density functional theory (DFT). Elastic constant matrixes were developed and results show that shear deformation is the easiest deformation type compared to other types for both Siderite and hematite crystal. Based on the elastic constant matrixes, bulk modulus and shear modulus of Siderite and hematite were calculated and their ratios of bulk modulus to shear modulus (B/G) are 2.17 and 2.61 respectively, which suggested that Siderite fractured more easily than hematite under the same stress level. Consequently, Young’s modulus, Poisson’s ratio, and compressibility were also calculated. Elastic anisotropy was investigated by computing the distribution of Young’s modulus with crystallographic direction. The color contour surfaces demonstrated that Siderite crystal was strongly anisotropic in comparison with hematite, and the minimum Young’s modulus of Siderite was only the half of that of hematite, which indicates the underlying mechanism that Siderite slimed easily when milled with hematite. In addition, this study provides a novel understanding concerning how mechanical properties of mineral crystals affect grinding processes, paving the way for selective grinding to avoid the easy-sliming of certain minerals.
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adsorption differences of sodium oleate on Siderite and hematite
Minerals Engineering, 2019Co-Authors: Li-xia Li, Zhitao Yuan, Partha Patra, P SomasundaranAbstract:Abstract To separate Siderite from carbonate-bearing iron ore efficiently, specific adsorption configurations and effective species were investigated to compare the adsorption differences of sodium oleate (NaOL) on Siderite and hematite surfaces. The species were analysed in neutral conditions, under which the direct flotation of Siderite from hematite and quartz was carried out. Changes in the zeta potential, Fourier-transform infrared spectroscopy spectra and X-ray photoelectron spectroscopy spectra caused by the adsorption of oleate species were compared to confirm the adsorbed species on Siderite and hematite. Molecular dynamics simulations were carried out to further verify the specific adsorption configurations. Chemisorption of oleate species was detected on both Siderite and hematite. The differences in the relative concentration changes of the elements indicate that NaOL worked on Siderite and hematite via adsorption of various groups or species. The main functional species were RCOO− for Siderite and RCOOH RCOO− for hematite. A strong chemical bond formed as RCOO− directly acted upon the Fe of Siderite. The carbon chains bent and interweaved to form the hydrophobic layer on Siderite. The two chains of RCOOH RCOO− laid upon hematite via weak chemical bonds and hydrogen bonds. Van der Waals and hydrophobic forces were the main interforces of the two chains.
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Adsorption of Pregelatinized Starch for Selective Flocculation and Flotation of Fine Siderite.
Langmuir : the ACS journal of surfaces and colloids, 2019Co-Authors: Haiqing Hao, Ponisseril Somasundaran, Zhitao YuanAbstract:Pregelatinized starch (PS) was used for the selective flocculation and flotation of fine Siderite in a carbonate-containing iron ore. With PS, the flotation of fine Siderite was improved. The repulsive forces between fine Siderite particles and the attractive forces between Siderite and hematite or quartz were decreased after treatment with PS, indicating that the aggregation of Siderite was enhanced and the aggregations of mixed minerals were weakened. An analysis of the changes in X-ray photoelectron spectra showed that coordination bonds were formed when PS was adsorbed on Siderite and hematite. However, PS could not adsorb on quartz. Moreover, the molecular simulation showed that the main mechanism for PS adsorption on Siderite was confirmed as a "tail model" with end -OH coordinated with Fe2+. The bridge connection of PS enhanced the flocculation of fine Siderite. The flotation of fine Siderite was also enhanced. For hematite treated with PS, the combination of coordination bond and hydrogen bond resulted in the "loop model" and "train model" as the main adsorption mechanisms of PS. The molecules covered the hematite surface and prevented the adsorption of the collector. The flotation of hematite was depressed. As a result, the selective flocculation and flotation of fine Siderite were realized.
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adsorption of pregelatinized starch for selective flocculation and flotation of fine Siderite
Langmuir, 2019Co-Authors: Li-xia Li, Zhitao YuanAbstract:Pregelatinized starch (PS) was used for the selective flocculation and flotation of fine Siderite in a carbonate-containing iron ore. With PS, the flotation of fine Siderite was improved. The repulsive forces between fine Siderite particles and the attractive forces between Siderite and hematite or quartz were decreased after treatment with PS, indicating that the aggregation of Siderite was enhanced and the aggregations of mixed minerals were weakened. An analysis of the changes in X-ray photoelectron spectra showed that coordination bonds were formed when PS was adsorbed on Siderite and hematite. However, PS could not adsorb on quartz. Moreover, the molecular simulation showed that the main mechanism for PS adsorption on Siderite was confirmed as a “tail model” with end −OH coordinated with Fe2+. The bridge connection of PS enhanced the flocculation of fine Siderite. The flotation of fine Siderite was also enhanced. For hematite treated with PS, the combination of coordination bond and hydrogen bond res...
Joe P Hamilton - One of the best experts on this subject based on the ideXlab platform.
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early diagenetic Siderite as an indicator of depositional environment in the triassic rewan group southern bowen basin eastern australia
Sedimentology, 1996Co-Authors: J Kassan, Julian C Baker, Joe P HamiltonAbstract:Early concretionary and non-concretionary Siderites are common in subsurface Triassic sandstones and mudrocks of the Rewan Group, southern Bowen Basin. A detailed petrological and stable isotopic study was carried out on these Siderites in order to provide information on the depositional environment of the host rocks. The Siderites are extremely pure, containing 85–97 mol% FeCO3, and are commonly enriched in manganese. δ13C (PDB) values are highly variable, ranging from - 18·4 to +2·9‰, whereas δ18O (PDB) values are very consistent, ranging from - 14·0 to - 10·2‰ (mean= - 11·9 ± 1·0‰). The elemental and oxygen isotopic composition of the Siderites indicates that only meteoric porewaters were involved in Siderite formation, implying that host rocks accumulated in totally non-marine environments. The carbon isotopic composition of the Siderites is interpreted to reflect mixing of bicarbonate/carbon dioxide generated by methane oxidation and methanogenesis. Very low δ13C values demonstrate that, contrary to current views, highly 13C-depleted Siderite can be produced at shallow burial depths in anoxic non-marine sediments.
P. Joe Hamilton - One of the best experts on this subject based on the ideXlab platform.
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Sandstone Diagenesis: Recent and Ancient - Early diagenetic Siderite as an indicator of depositional environment in the Triassic Rewan Group, southern Bowen Basin, eastern Australia
Sedimentology, 1996Co-Authors: Julian C Baker, J Kassan, P. Joe HamiltonAbstract:Early concretionary and non-concretionary Siderites are common in subsurface Triassic sandstones and mudrocks of the Rewan Group, southern Bowen Basin. A detailed petrological and stable isotopic study was carried out on these Siderites in order to provide information on the depositional environment of the host rocks. The Siderites are extremely pure, containing 85–97 mol% FeCO3, and are commonly enriched in manganese. δ13C (PDB) values are highly variable, ranging from - 18·4 to +2·9‰, whereas δ18O (PDB) values are very consistent, ranging from - 14·0 to - 10·2‰ (mean= - 11·9 ± 1·0‰). The elemental and oxygen isotopic composition of the Siderites indicates that only meteoric porewaters were involved in Siderite formation, implying that host rocks accumulated in totally non-marine environments. The carbon isotopic composition of the Siderites is interpreted to reflect mixing of bicarbonate/carbon dioxide generated by methane oxidation and methanogenesis. Very low δ13C values demonstrate that, contrary to current views, highly 13C-depleted Siderite can be produced at shallow burial depths in anoxic non-marine sediments.
J Kassan - One of the best experts on this subject based on the ideXlab platform.
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early diagenetic Siderite as an indicator of depositional environment in the triassic rewan group southern bowen basin eastern australia
Sedimentology, 1996Co-Authors: J Kassan, Julian C Baker, Joe P HamiltonAbstract:Early concretionary and non-concretionary Siderites are common in subsurface Triassic sandstones and mudrocks of the Rewan Group, southern Bowen Basin. A detailed petrological and stable isotopic study was carried out on these Siderites in order to provide information on the depositional environment of the host rocks. The Siderites are extremely pure, containing 85–97 mol% FeCO3, and are commonly enriched in manganese. δ13C (PDB) values are highly variable, ranging from - 18·4 to +2·9‰, whereas δ18O (PDB) values are very consistent, ranging from - 14·0 to - 10·2‰ (mean= - 11·9 ± 1·0‰). The elemental and oxygen isotopic composition of the Siderites indicates that only meteoric porewaters were involved in Siderite formation, implying that host rocks accumulated in totally non-marine environments. The carbon isotopic composition of the Siderites is interpreted to reflect mixing of bicarbonate/carbon dioxide generated by methane oxidation and methanogenesis. Very low δ13C values demonstrate that, contrary to current views, highly 13C-depleted Siderite can be produced at shallow burial depths in anoxic non-marine sediments.
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Sandstone Diagenesis: Recent and Ancient - Early diagenetic Siderite as an indicator of depositional environment in the Triassic Rewan Group, southern Bowen Basin, eastern Australia
Sedimentology, 1996Co-Authors: Julian C Baker, J Kassan, P. Joe HamiltonAbstract:Early concretionary and non-concretionary Siderites are common in subsurface Triassic sandstones and mudrocks of the Rewan Group, southern Bowen Basin. A detailed petrological and stable isotopic study was carried out on these Siderites in order to provide information on the depositional environment of the host rocks. The Siderites are extremely pure, containing 85–97 mol% FeCO3, and are commonly enriched in manganese. δ13C (PDB) values are highly variable, ranging from - 18·4 to +2·9‰, whereas δ18O (PDB) values are very consistent, ranging from - 14·0 to - 10·2‰ (mean= - 11·9 ± 1·0‰). The elemental and oxygen isotopic composition of the Siderites indicates that only meteoric porewaters were involved in Siderite formation, implying that host rocks accumulated in totally non-marine environments. The carbon isotopic composition of the Siderites is interpreted to reflect mixing of bicarbonate/carbon dioxide generated by methane oxidation and methanogenesis. Very low δ13C values demonstrate that, contrary to current views, highly 13C-depleted Siderite can be produced at shallow burial depths in anoxic non-marine sediments.
