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Young-shin Jun - One of the best experts on this subject based on the ideXlab platform.
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supercritical co2 brine induced dissolution swelling and Secondary Mineral formation on phlogopite surfaces at 75 95 c and 75 atm
Energy and Environmental Science, 2012Co-Authors: Daniel J Garcia, Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:To safely implement geologic carbon sequestration (GCS), a better understanding of geochemical reactions at supercritical CO2 (scCO2)–brine–clay Mineral interfaces is necessary. This work investigated phlogopite dissolution and Secondary Mineral formation after freshly cleaved (001) surfaces were exposed to scCO2–brine systems. Phlogopite was used as a model clay Mineral, and scCO2–1 M NaCl–phlogopite systems at 75 °C and 75 atm were chosen to mimic CO2 storage conditions in deep saline aquifers. Additional experiments were also performed at 95 °C to explore the effect of temperature on phlogopite dissolution. The dissolution activation energies for each element were calculated to be 64.2 kJ mol−1 for Si, 53.6 kJ mol−1 for Mg, and 78.4 kJ mol−1 for Al. Over 43 h of reaction time, the activation energy for K dissolution was calculated to be 35.9 kJ mol−1. A whole-Mineral activation energy for phlogopite, 62.5 kJ mol−1, was estimated from the weighted mean values of the activation energies of the framework elements (Al, Si, and Mg). Swelling of the phlogopite outer layers, dissolution pit formation, and precipitation of both illite and amorphous silica were dominant at both temperatures. At 75 °C, normalized volumetric surface coverage (μm3/μm2) was 0.34 ± 0.74 for illite and 0.05 ± 0.90 for amorphous silica nanoparticles.
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Effects of organic ligands on supercritical CO2-induced phlogopite dissolution and Secondary Mineral formation
Chemical Geology, 2011Co-Authors: Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:Abstract To evaluate the long-term and short-term risks associated with geologic CO 2 sequestration (GCS), we need to understand both the reactions at supercritical CO 2 (scCO 2 )–saline water–rock interfaces, and the environmental factors affecting these interactions. This research investigated the effects of four organic ligands—oxalate, malonate, acetate, and propionate—on the dissolution and surface morphological changes of phlogopite [KMg 2.87 Si 3.07 Al 1.23 O 10 (F,OH) 2 ] under GCS conditions (95 °C and 102 atm). Phlogopite was chosen as a model clay Mineral in potential GCS sites. After CO 2 injection, the dissolution of CO 2 should cause a decrease in saline water pH, increasing phlogopite dissolution. This effect can be lessened by the buffering capacity of organic ligands. However, in this study, the ligands that formed strong complexes with surface metals (i.e., oxalate) caused phlogopite dissolution rates to increase via ligand-promoted dissolution, although the pH increased. The experimentally observed dissolution rates of phlogopite were in the order of: oxalate > malonate > acetate ≈ propionate. In addition, based on results from ion chromatography, oxalate and malonate concentrations were stable in our reaction systems; however, aqueous acetate and propionate concentrations continuously decreased due to solvent extraction of acetic acid and propionic acid by scCO 2 at 95 °C and 102 atm. After 159 h, all of the acetate and propionate were removed from aqueous solutions. Although the aqueous species in the bulk solution were not supersaturated with respect to potential Secondary Mineral phases, interestingly, in the presence of oxalate, nanoscale precipitation of amorphous silica and fibrous illite was observed at the phlogopite surface only 3 h after CO 2 injection. At this early reaction time, illite fibers formed a connected, hexagonal framework on phlogopite basal surfaces, but at a later reaction time, these structures detached from the surface and triggered the formation of dissolution channels. In addition, kaolinite, boehmite, diaspore, and gibbsite were identified as Secondary Mineral phases. These results provide new information towards understanding organic species' interactions at scCO 2 –saline water–rock interfaces in deep saline aquifers.
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Effects of Salinity and the Extent of Water on Supercritical CO2-Induced Phlogopite Dissolution and Secondary Mineral Formation
Environmental science & technology, 2011Co-Authors: Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:To ensure the viability of geologic CO2 sequestration (GCS), we need a holistic understanding of reactions at supercritical CO2 (scCO2)−saline water−rock interfaces and the environmental factors affecting these interactions. This research investigated the effects of salinity and the extent of water on the dissolution and surface morphological changes of phlogopite [KMg2.87Si3.07Al1.23O10(F,OH)2], a model clay Mineral in potential GCS sites. Salinity enhanced the dissolution of phlogopite and affected the location, shape, size, and phase of Secondary Minerals. In low salinity solutions, nanoscale particles of Secondary Minerals formed much faster, and there were more nanoparticles than in high salinity solutions. The effect of water extent was investigated by comparing scCO2−H2O(g)−phlogopite and scCO2−H2O(l)−phlogopite interactions. Experimental results suggested that the presence of a thin water film adsorbed on the phlogopite surface caused the formation of dissolution pits and a surface coating of seco...
Ermanno Galli - One of the best experts on this subject based on the ideXlab platform.
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source and genesis of sulphate and phosphate sulphate Minerals in a quartz sandstone cave environment
Sedimentology, 2014Co-Authors: Francesco Sauro, Tomaso R R Bontognali, Jo De Waele, Stefano M Bernasconi, Nicola Tisato, Ermanno GalliAbstract:Gypsum (CaSO4·2H2O), alunite (KAl3(SO4)2(OH)6), and rare phosphate–sulphate sanjuanite Al2(PO4)(SO4)(OH) 9(H2O) and rossiantonite (Al3(PO4)(SO4) 2(OH)2(H2O)14) have recently been identified as Secondary Mineral deposits in different quartz-sandstone caves in the Gran Sabana region, Venezuela. Due to the extended time scale required for speleogenesis in the hard and barely soluble quartz-sandstone lithology, these caves are considered to be as old as 20 to 30 My. The study of these peculiar Secondary Mineral deposits potentially reveals important insights for understanding the interaction between deep, superficial and atmospheric processes over thousands to perhaps millions of years. In this study, chemical and petrographic analyses of potential host rock sources, sulphur and oxygen isotope ratios, and meteorological, hydrological and geographical data are used to investigate the origin of sulphates and phospho–sulphates. The results suggest that the deposition of sulphates in these caves is not linked to the quartz-sandstone host rock. Rather, these Mineral deposits originate from an external atmospheric sulphate source, with potential contributions of marine non-sea salt sulphates, terrestrial dimethyl sulphide and microbially reduced H2S from the forests or peatbogs within the watershed. Air currents within the caves are the most plausible means of transport for aerosols, driving the accumulation of sulphates and other Secondary Minerals in specific locations. Moreover, the studied sulphate Minerals often co-occur with silica speleothems of biological origin. Although this association would suggest a possible biogenic origin for the sulphates as well, direct evidence proving that microbes are involved in their formation is absent. Nonetheless, this study demonstrates that these quartz-sandstone caves accumulate and preserve allogenic sulphates, playing a yet unrecognized role in the sulphur cycle of tropical environments.
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Source and genesis of sulphate and phosphate–sulphate Minerals in a quartz-sandstone cave environment
Sedimentology, 2014Co-Authors: Francesco Sauro, Tomaso R R Bontognali, Jo De Waele, Stefano M Bernasconi, Nicola Tisato, Ermanno GalliAbstract:Gypsum (CaSO4·2H2O), alunite (KAl3(SO4)2(OH)6), and rare phosphate–sulphate sanjuanite Al2(PO4)(SO4)(OH) 9(H2O) and rossiantonite (Al3(PO4)(SO4) 2(OH)2(H2O)14) have recently been identified as Secondary Mineral deposits in different quartz-sandstone caves in the Gran Sabana region, Venezuela. Due to the extended time scale required for speleogenesis in the hard and barely soluble quartz-sandstone lithology, these caves are considered to be as old as 20 to 30 My. The study of these peculiar Secondary Mineral deposits potentially reveals important insights for understanding the interaction between deep, superficial and atmospheric processes over thousands to perhaps millions of years. In this study, chemical and petrographic analyses of potential host rock sources, sulphur and oxygen isotope ratios, and meteorological, hydrological and geographical data are used to investigate the origin of sulphates and phospho–sulphates. The results suggest that the deposition of sulphates in these caves is not linked to the quartz-sandstone host rock. Rather, these Mineral deposits originate from an external atmospheric sulphate source, with potential contributions of marine non-sea salt sulphates, terrestrial dimethyl sulphide and microbially reduced H2S from the forests or peatbogs within the watershed. Air currents within the caves are the most plausible means of transport for aerosols, driving the accumulation of sulphates and other Secondary Minerals in specific locations. Moreover, the studied sulphate Minerals often co-occur with silica speleothems of biological origin. Although this association would suggest a possible biogenic origin for the sulphates as well, direct evidence proving that microbes are involved in their formation is absent. Nonetheless, this study demonstrates that these quartz-sandstone caves accumulate and preserve allogenic sulphates, playing a yet unrecognized role in the sulphur cycle of tropical environments.
Hongbo Shao - One of the best experts on this subject based on the ideXlab platform.
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supercritical co2 brine induced dissolution swelling and Secondary Mineral formation on phlogopite surfaces at 75 95 c and 75 atm
Energy and Environmental Science, 2012Co-Authors: Daniel J Garcia, Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:To safely implement geologic carbon sequestration (GCS), a better understanding of geochemical reactions at supercritical CO2 (scCO2)–brine–clay Mineral interfaces is necessary. This work investigated phlogopite dissolution and Secondary Mineral formation after freshly cleaved (001) surfaces were exposed to scCO2–brine systems. Phlogopite was used as a model clay Mineral, and scCO2–1 M NaCl–phlogopite systems at 75 °C and 75 atm were chosen to mimic CO2 storage conditions in deep saline aquifers. Additional experiments were also performed at 95 °C to explore the effect of temperature on phlogopite dissolution. The dissolution activation energies for each element were calculated to be 64.2 kJ mol−1 for Si, 53.6 kJ mol−1 for Mg, and 78.4 kJ mol−1 for Al. Over 43 h of reaction time, the activation energy for K dissolution was calculated to be 35.9 kJ mol−1. A whole-Mineral activation energy for phlogopite, 62.5 kJ mol−1, was estimated from the weighted mean values of the activation energies of the framework elements (Al, Si, and Mg). Swelling of the phlogopite outer layers, dissolution pit formation, and precipitation of both illite and amorphous silica were dominant at both temperatures. At 75 °C, normalized volumetric surface coverage (μm3/μm2) was 0.34 ± 0.74 for illite and 0.05 ± 0.90 for amorphous silica nanoparticles.
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Effects of organic ligands on supercritical CO2-induced phlogopite dissolution and Secondary Mineral formation
Chemical Geology, 2011Co-Authors: Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:Abstract To evaluate the long-term and short-term risks associated with geologic CO 2 sequestration (GCS), we need to understand both the reactions at supercritical CO 2 (scCO 2 )–saline water–rock interfaces, and the environmental factors affecting these interactions. This research investigated the effects of four organic ligands—oxalate, malonate, acetate, and propionate—on the dissolution and surface morphological changes of phlogopite [KMg 2.87 Si 3.07 Al 1.23 O 10 (F,OH) 2 ] under GCS conditions (95 °C and 102 atm). Phlogopite was chosen as a model clay Mineral in potential GCS sites. After CO 2 injection, the dissolution of CO 2 should cause a decrease in saline water pH, increasing phlogopite dissolution. This effect can be lessened by the buffering capacity of organic ligands. However, in this study, the ligands that formed strong complexes with surface metals (i.e., oxalate) caused phlogopite dissolution rates to increase via ligand-promoted dissolution, although the pH increased. The experimentally observed dissolution rates of phlogopite were in the order of: oxalate > malonate > acetate ≈ propionate. In addition, based on results from ion chromatography, oxalate and malonate concentrations were stable in our reaction systems; however, aqueous acetate and propionate concentrations continuously decreased due to solvent extraction of acetic acid and propionic acid by scCO 2 at 95 °C and 102 atm. After 159 h, all of the acetate and propionate were removed from aqueous solutions. Although the aqueous species in the bulk solution were not supersaturated with respect to potential Secondary Mineral phases, interestingly, in the presence of oxalate, nanoscale precipitation of amorphous silica and fibrous illite was observed at the phlogopite surface only 3 h after CO 2 injection. At this early reaction time, illite fibers formed a connected, hexagonal framework on phlogopite basal surfaces, but at a later reaction time, these structures detached from the surface and triggered the formation of dissolution channels. In addition, kaolinite, boehmite, diaspore, and gibbsite were identified as Secondary Mineral phases. These results provide new information towards understanding organic species' interactions at scCO 2 –saline water–rock interfaces in deep saline aquifers.
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Effects of Salinity and the Extent of Water on Supercritical CO2-Induced Phlogopite Dissolution and Secondary Mineral Formation
Environmental science & technology, 2011Co-Authors: Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:To ensure the viability of geologic CO2 sequestration (GCS), we need a holistic understanding of reactions at supercritical CO2 (scCO2)−saline water−rock interfaces and the environmental factors affecting these interactions. This research investigated the effects of salinity and the extent of water on the dissolution and surface morphological changes of phlogopite [KMg2.87Si3.07Al1.23O10(F,OH)2], a model clay Mineral in potential GCS sites. Salinity enhanced the dissolution of phlogopite and affected the location, shape, size, and phase of Secondary Minerals. In low salinity solutions, nanoscale particles of Secondary Minerals formed much faster, and there were more nanoparticles than in high salinity solutions. The effect of water extent was investigated by comparing scCO2−H2O(g)−phlogopite and scCO2−H2O(l)−phlogopite interactions. Experimental results suggested that the presence of a thin water film adsorbed on the phlogopite surface caused the formation of dissolution pits and a surface coating of seco...
Francesco Sauro - One of the best experts on this subject based on the ideXlab platform.
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source and genesis of sulphate and phosphate sulphate Minerals in a quartz sandstone cave environment
Sedimentology, 2014Co-Authors: Francesco Sauro, Tomaso R R Bontognali, Jo De Waele, Stefano M Bernasconi, Nicola Tisato, Ermanno GalliAbstract:Gypsum (CaSO4·2H2O), alunite (KAl3(SO4)2(OH)6), and rare phosphate–sulphate sanjuanite Al2(PO4)(SO4)(OH) 9(H2O) and rossiantonite (Al3(PO4)(SO4) 2(OH)2(H2O)14) have recently been identified as Secondary Mineral deposits in different quartz-sandstone caves in the Gran Sabana region, Venezuela. Due to the extended time scale required for speleogenesis in the hard and barely soluble quartz-sandstone lithology, these caves are considered to be as old as 20 to 30 My. The study of these peculiar Secondary Mineral deposits potentially reveals important insights for understanding the interaction between deep, superficial and atmospheric processes over thousands to perhaps millions of years. In this study, chemical and petrographic analyses of potential host rock sources, sulphur and oxygen isotope ratios, and meteorological, hydrological and geographical data are used to investigate the origin of sulphates and phospho–sulphates. The results suggest that the deposition of sulphates in these caves is not linked to the quartz-sandstone host rock. Rather, these Mineral deposits originate from an external atmospheric sulphate source, with potential contributions of marine non-sea salt sulphates, terrestrial dimethyl sulphide and microbially reduced H2S from the forests or peatbogs within the watershed. Air currents within the caves are the most plausible means of transport for aerosols, driving the accumulation of sulphates and other Secondary Minerals in specific locations. Moreover, the studied sulphate Minerals often co-occur with silica speleothems of biological origin. Although this association would suggest a possible biogenic origin for the sulphates as well, direct evidence proving that microbes are involved in their formation is absent. Nonetheless, this study demonstrates that these quartz-sandstone caves accumulate and preserve allogenic sulphates, playing a yet unrecognized role in the sulphur cycle of tropical environments.
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Source and genesis of sulphate and phosphate–sulphate Minerals in a quartz-sandstone cave environment
Sedimentology, 2014Co-Authors: Francesco Sauro, Tomaso R R Bontognali, Jo De Waele, Stefano M Bernasconi, Nicola Tisato, Ermanno GalliAbstract:Gypsum (CaSO4·2H2O), alunite (KAl3(SO4)2(OH)6), and rare phosphate–sulphate sanjuanite Al2(PO4)(SO4)(OH) 9(H2O) and rossiantonite (Al3(PO4)(SO4) 2(OH)2(H2O)14) have recently been identified as Secondary Mineral deposits in different quartz-sandstone caves in the Gran Sabana region, Venezuela. Due to the extended time scale required for speleogenesis in the hard and barely soluble quartz-sandstone lithology, these caves are considered to be as old as 20 to 30 My. The study of these peculiar Secondary Mineral deposits potentially reveals important insights for understanding the interaction between deep, superficial and atmospheric processes over thousands to perhaps millions of years. In this study, chemical and petrographic analyses of potential host rock sources, sulphur and oxygen isotope ratios, and meteorological, hydrological and geographical data are used to investigate the origin of sulphates and phospho–sulphates. The results suggest that the deposition of sulphates in these caves is not linked to the quartz-sandstone host rock. Rather, these Mineral deposits originate from an external atmospheric sulphate source, with potential contributions of marine non-sea salt sulphates, terrestrial dimethyl sulphide and microbially reduced H2S from the forests or peatbogs within the watershed. Air currents within the caves are the most plausible means of transport for aerosols, driving the accumulation of sulphates and other Secondary Minerals in specific locations. Moreover, the studied sulphate Minerals often co-occur with silica speleothems of biological origin. Although this association would suggest a possible biogenic origin for the sulphates as well, direct evidence proving that microbes are involved in their formation is absent. Nonetheless, this study demonstrates that these quartz-sandstone caves accumulate and preserve allogenic sulphates, playing a yet unrecognized role in the sulphur cycle of tropical environments.
Jessica R. Ray - One of the best experts on this subject based on the ideXlab platform.
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supercritical co2 brine induced dissolution swelling and Secondary Mineral formation on phlogopite surfaces at 75 95 c and 75 atm
Energy and Environmental Science, 2012Co-Authors: Daniel J Garcia, Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:To safely implement geologic carbon sequestration (GCS), a better understanding of geochemical reactions at supercritical CO2 (scCO2)–brine–clay Mineral interfaces is necessary. This work investigated phlogopite dissolution and Secondary Mineral formation after freshly cleaved (001) surfaces were exposed to scCO2–brine systems. Phlogopite was used as a model clay Mineral, and scCO2–1 M NaCl–phlogopite systems at 75 °C and 75 atm were chosen to mimic CO2 storage conditions in deep saline aquifers. Additional experiments were also performed at 95 °C to explore the effect of temperature on phlogopite dissolution. The dissolution activation energies for each element were calculated to be 64.2 kJ mol−1 for Si, 53.6 kJ mol−1 for Mg, and 78.4 kJ mol−1 for Al. Over 43 h of reaction time, the activation energy for K dissolution was calculated to be 35.9 kJ mol−1. A whole-Mineral activation energy for phlogopite, 62.5 kJ mol−1, was estimated from the weighted mean values of the activation energies of the framework elements (Al, Si, and Mg). Swelling of the phlogopite outer layers, dissolution pit formation, and precipitation of both illite and amorphous silica were dominant at both temperatures. At 75 °C, normalized volumetric surface coverage (μm3/μm2) was 0.34 ± 0.74 for illite and 0.05 ± 0.90 for amorphous silica nanoparticles.
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Effects of organic ligands on supercritical CO2-induced phlogopite dissolution and Secondary Mineral formation
Chemical Geology, 2011Co-Authors: Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:Abstract To evaluate the long-term and short-term risks associated with geologic CO 2 sequestration (GCS), we need to understand both the reactions at supercritical CO 2 (scCO 2 )–saline water–rock interfaces, and the environmental factors affecting these interactions. This research investigated the effects of four organic ligands—oxalate, malonate, acetate, and propionate—on the dissolution and surface morphological changes of phlogopite [KMg 2.87 Si 3.07 Al 1.23 O 10 (F,OH) 2 ] under GCS conditions (95 °C and 102 atm). Phlogopite was chosen as a model clay Mineral in potential GCS sites. After CO 2 injection, the dissolution of CO 2 should cause a decrease in saline water pH, increasing phlogopite dissolution. This effect can be lessened by the buffering capacity of organic ligands. However, in this study, the ligands that formed strong complexes with surface metals (i.e., oxalate) caused phlogopite dissolution rates to increase via ligand-promoted dissolution, although the pH increased. The experimentally observed dissolution rates of phlogopite were in the order of: oxalate > malonate > acetate ≈ propionate. In addition, based on results from ion chromatography, oxalate and malonate concentrations were stable in our reaction systems; however, aqueous acetate and propionate concentrations continuously decreased due to solvent extraction of acetic acid and propionic acid by scCO 2 at 95 °C and 102 atm. After 159 h, all of the acetate and propionate were removed from aqueous solutions. Although the aqueous species in the bulk solution were not supersaturated with respect to potential Secondary Mineral phases, interestingly, in the presence of oxalate, nanoscale precipitation of amorphous silica and fibrous illite was observed at the phlogopite surface only 3 h after CO 2 injection. At this early reaction time, illite fibers formed a connected, hexagonal framework on phlogopite basal surfaces, but at a later reaction time, these structures detached from the surface and triggered the formation of dissolution channels. In addition, kaolinite, boehmite, diaspore, and gibbsite were identified as Secondary Mineral phases. These results provide new information towards understanding organic species' interactions at scCO 2 –saline water–rock interfaces in deep saline aquifers.
-
Effects of Salinity and the Extent of Water on Supercritical CO2-Induced Phlogopite Dissolution and Secondary Mineral Formation
Environmental science & technology, 2011Co-Authors: Hongbo Shao, Jessica R. Ray, Young-shin JunAbstract:To ensure the viability of geologic CO2 sequestration (GCS), we need a holistic understanding of reactions at supercritical CO2 (scCO2)−saline water−rock interfaces and the environmental factors affecting these interactions. This research investigated the effects of salinity and the extent of water on the dissolution and surface morphological changes of phlogopite [KMg2.87Si3.07Al1.23O10(F,OH)2], a model clay Mineral in potential GCS sites. Salinity enhanced the dissolution of phlogopite and affected the location, shape, size, and phase of Secondary Minerals. In low salinity solutions, nanoscale particles of Secondary Minerals formed much faster, and there were more nanoparticles than in high salinity solutions. The effect of water extent was investigated by comparing scCO2−H2O(g)−phlogopite and scCO2−H2O(l)−phlogopite interactions. Experimental results suggested that the presence of a thin water film adsorbed on the phlogopite surface caused the formation of dissolution pits and a surface coating of seco...