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Vladimir A. Samarkin - One of the best experts on this subject based on the ideXlab platform.
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Carbon Mineralization in Laptev and East Siberian sea shelf and slope sediment
Biogeosciences, 2018Co-Authors: Volker Brüchert, Lisa Bröder, Joanna E. Sawicka, Tommaso Tesi, Samantha P. Joye, Xiaole Sun, Igor Semiletov, Vladimir A. SamarkinAbstract:Abstract. The Siberian Arctic Sea shelf and slope is a key region for the degradation of terrestrial organic material transported from the organic-Carbon-rich permafrost regions of Siberia. We report on sediment Carbon Mineralization rates based on O 2 microelectrode profiling; intact sediment core incubations; 35 S-sulfate tracer experiments; pore-water dissolved inorganic Carbon (DIC); δ13 C DIC ; and iron, manganese, and ammonium concentrations from 20 shelf and slope stations. This data set provides a spatial overview of sediment Carbon Mineralization rates and pathways over large parts of the outer Laptev and East Siberian Arctic shelf and slope and allows us to assess degradation rates and efficiency of Carbon burial in these sediments. Rates of oxygen uptake and iron and manganese reduction were comparable to temperate shelf and slope environments, but bacterial sulfate reduction rates were comparatively low. In the topmost 50 cm of sediment, aerobic Carbon Mineralization dominated degradation and comprised on average 84 % of the depth-integrated Carbon Mineralization. Oxygen uptake rates and anaerobic Carbon Mineralization rates were higher in the eastern East Siberian Sea shelf compared to the Laptev Sea shelf. DIC ∕ NH 4 + ratios in pore waters and the stable Carbon isotope composition of remineralized DIC indicated that the degraded organic matter on the Siberian shelf and slope was a mixture of marine and terrestrial organic matter. Based on dual end-member calculations, the terrestrial organic Carbon contribution varied between 32 and 36 %, with a higher contribution in the Laptev Sea than in the East Siberian Sea. Extrapolation of the measured degradation rates using isotope end-member apportionment over the outer shelf of the Laptev and East Siberian seas suggests that about 16 Tg C yr −1 is respired in the outer shelf seafloor sediment. Of the organic matter buried below the oxygen penetration depth, between 0.6 and 1.3 Tg C yr −1 is degraded by anaerobic processes, with a terrestrial organic Carbon contribution ranging between 0.3 and 0.5 Tg yr −1 .
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Carbon Mineralization in Laptev and East Siberian Sea shelf and slope sediment
2017Co-Authors: Volker Brüchert, Lisa Bröder, Joanna E. Sawicka, Tommaso Tesi, Samantha P. Joye, Xiaole Sun, Igor Semiletov, Vladimir A. SamarkinAbstract:Abstract. The Siberian Arctic Sea shelf and slope is a key region for the degradation of terrestrial organic material transported from the organic Carbon-rich permafrost regions of Siberia. We report on sediment Carbon Mineralization rates based on O2 microelectrode profiling, intact sediment core incubations, 35S-sulfate tracer experiments, porewater dissolved inorganic Carbon (DIC), δ13CDIC, and iron, manganese, and ammonium concentrations from 20 shelf and slope stations. This data set provides a spatial overview of sediment Carbon Mineralization rates and pathways over large parts of the outer Laptev and East Siberian Arctic shelf and slope, and allowed us to assess degradation rates and efficiency of Carbon burial in these sediments. Rates of oxygen uptake and iron and manganese reduction were comparable to temperate shelf and slope environments, but bacterial sulfate reduction rates were comparatively low. In the topmost 20 to 50 cm of sediment, aerobic Carbon Mineralization dominated degradation and comprised on average 82 % of the depth-integrated Carbon Mineralization. Oxygen uptake rates and 35S-sulfate reduction rates were higher in the eastern East Siberian Sea shelf compared to the Laptev Sea shelf. DIC/NH4+ ratios in porewaters and the stable Carbon isotope composition of remineralized DIC indicated that the degraded organic matter on the Siberian shelf and slope was a mixture of marine and terrestrial organic matter. Based on dual end member calculations, the terrestrial organic Carbon contribution varied between 32 % and 36 %, with a higher contribution in the Laptev Sea than in the East Siberian Sea. Extrapolation of the measured degradation rates using isotope end member apportionment over the outer shelf of the Laptev and East Siberian Sea suggests that about 16 Tg C per year are respired in the outer shelf sea floor sediment. Of the organic matter buried below the oxygen penetration depth, between 0.6 and 1.3 Tg C per year are degraded by anaerobic processes, with a terrestrial organic Carbon contribution ranging between 0.3 and 0.5 Tg per year.
Peter B. Kelemen - One of the best experts on this subject based on the ideXlab platform.
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Engineered Carbon Mineralization in ultramafic rocks for CO2 removal from air: Review and new insights
Chemical Geology, 2020Co-Authors: Peter B. Kelemen, G. M. Dipple, Noah Mcqueen, Jennifer Wilcox, Phil Renforth, Amelia N. Paukert VankeurenAbstract:Abstract Carbon Dioxide removal from air (CDR) combined with permanent solid storage can be accomplished via Carbon Mineralization in ultramafic rocks in at least four ways: 1. Surficial CDR: CO2-bearing air and surface waters are reacted with crushed and or ground mine tailings, alkaline industrial wastes, or sedimentary formations rich in reactive rock fragments, all with a high proportion of reactive surface area. This can be implemented at a low cost, but most proposed methods have a very large area footprint at the gigatonne scale. The area requirement can be greatly reduced by calcining (heating to produce pure CO2 for permanent storage or use) followed by recycling of MgO, CaO, Na2O, … Such looping methods have predicted costs that are as low or lower than for direct air capture with synthetic sorbents or solvents (DACSS), and a similar area footprint. 2. In situ CDR: CO2-bearing surface waters are circulated through rock formations at depth. These methods potentially have a cost similar to that of surficial Carbon Mineralization, and a giant storage capacity with reduced surface area requirements, but they involve uncertain feedbacks between permeability, reactive surface area, and reaction rate, providing a fascinating topic for fundamental research. Furthermore, the size, injectivity, permeability, geomechanics, and microstructure of key subsurface reservoirs for in situ CDR remain almost entirely unexplored. 3&4. Combined partial enrichment of CO2 using direct air capture with synthetic sorbents (DACSS) plus surficial Carbon Mineralization (3) or in situ Carbon Mineralization (4). Energy requirements and total costs for partial enrichment of CO2 are substantially lower than for enrichment to high purity. CO2 enriched air can be sparged through mine tailings at the surface, and/or through water to increase dissolved Carbon concentrations prior to circulation through rock reactants. Such combined or hybrid approaches have not been investigated thoroughly, and offer many avenues for optimization.
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In situ Carbon Mineralization in ultramafic rocks: Natural processes and possible engineered methods
Energy Procedia, 2018Co-Authors: Peter B. Kelemen, Greeshma Gadikota, Roger D. Aines, E. Bennett, Sally M. Benson, E. Carter, J. A. Coggon, J. C. De Obeso, Owen Evans, G. M. DippleAbstract:Abstract In this invited review, we summarize the main results of ongoing research on “in situ” Carbon Mineralization in ultramafic rocks, including outcrop studies in Oman (e.g., [1, 2]), investigation of Carbon mass transfer in subduction zones from the Oman Drilling Project (e.g., [3-7]), laboratory investigations (e.g., [8-12]) and numerical modeling (e.g., [13-17]) of the pressure of crystallization and reaction-driven cracking, and assessment of the rate, cost and capacity of various proposed methods for engineered Carbon Mineralization [18, 19].
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experimental evidence for chemo mechanical coupling during Carbon Mineralization in ultramafic rocks
Earth and Planetary Science Letters, 2017Co-Authors: Peter B. Kelemen, H P Lisabeth, Wenlu Zhu, Anastasia G IlgenAbstract:Abstract Storing Carbon dioxide in the subsurface as Carbonate minerals has the benefit of long-term stability and immobility. Ultramafic rock formations have been suggested as a potential reservoir for this type of storage due to the availability of cations to react with dissolved Carbon dioxide and the fast reaction rates associated with minerals common in ultramafic formations; however, the rapid reactions have the potential to couple with the mechanical and hydraulic behavior of the rocks and little is known about the extent and mechanisms of this coupling. In this study, we argue that the dissolution of primary minerals and the precipitation of secondary minerals along pre-existing fractures in samples lead to reductions in both the apparent Young's modulus and shear strength of aggregates, accompanied by reduction in permeability. Hydrostatic and triaxial deformation experiments were run on dunite samples saturated with de-ionized water and Carbon dioxide-rich solutions while stress, strain, permeability and pore fluid chemistry were monitored. Sample microstructures were examined after reaction and deformation using scanning electron microscopy (SEM). The results show that channelized dissolution and Carbonate mineral precipitation in the samples saturated with Carbon dioxide-rich solutions modify the structure of grain boundaries, leading to the observed reductions in stiffness, strength and permeability. A geochemical model was run to help interpret fluid chemical data, and we find that the apparent reaction rates in our experiments are faster than rates calculated from powder reactors, suggesting mechanically enhanced reaction rates. In conclusion, we find that chemo-mechanical coupling during Carbon Mineralization in dunites leads to substantial modification of mechanical and hydraulic behavior that needs to be accounted for in future modeling efforts of in situ Carbon Mineralization projects.
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Carbon Mineralization: From Natural Analogues to Engineered Systems
Reviews in Mineralogy and Geochemistry, 2013Co-Authors: Ian M. Power, Anna L. Harrison, Gregory M. Dipple, Siobhan A. Wilson, Peter B. Kelemen, Michael Hitch, Gordon SouthamAbstract:Carbon Mineralization sequesters CO2 by reaction of alkaline earth metal bearing silicate and hydroxide minerals with CO2 to form stable Carbonate minerals. Seifritz (1990) proposed harnessing this natural process as a method for sequestration of anthropogenic CO2. It was first studied in detail as an industrial process by Lackner et al. (1995), which is often referred to as “mineral Carbonation.” Much of this early research aimed to capitalize on the globally abundant natural deposits of ultramafic and mafic rocks, which are rich in alkaline earth metals, in addition to the long-term stability of the resultant Carbonate minerals (Lackner et al. 1995). More recently, other process routes have been investigated that rely on feedstocks other than naturally occurring minerals (e.g., industrial wastes) as a source of cations for Carbonate precipitation. Therefore, we use the more general term “Carbon Mineralization” to refer to any process that sequesters CO2 as a solid Carbonate phase. The main advantages of Carbon Mineralization as a CO2 storage method are that the reactions are thermodynamically favored, the Carbonation processes can be readily controlled and manipulated, and the resulting product is benign and stable over geological time. We begin this review with an overview of the fundamental processes that are relevant to Carbon Mineralization, which provides a basic framework in which to understand CO2 sequestration strategies based on Carbon Mineralization. We next discuss natural analogues to engineered systems, focusing on (1) exhumed hydrothermal systems in peridotite that have formed listvenite (magnesite + quartz) and soapstone and (2) shallow subsurface peridotite weathering processes and related alkaline springs that form Carbonate veins, surficial travertine deposits, and hydromagnesite–magnesite playas. The propensity to form Carbonate minerals in these ultramafic terranes reflects the thermodynamic instability of Mg-silicate minerals in the presence of CO2. …
Min Luo - One of the best experts on this subject based on the ideXlab platform.
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benthic Carbon Mineralization in hadal trenches insights from in situ determination of benthic oxygen consumption
Geophysical Research Letters, 2018Co-Authors: Min Luo, Frank Wenzhöfer, Ronnie N. Glud, Binbin Pan, Gang Lin, Duofu ChenAbstract:Hadal trenches have been proposed as depocenters of organic material and hotspots for organic matter Mineralization. In this study, we for the first time quantified the total benthic O2 uptake in hadal trenches using in-situ chamber incubations. Three trenches in the tropical Pacific were targeted and exhibited relatively high diagenetic activity given the great water depths, i.e., the Mariana Trench (2.0×102 μmol O2 m-2 d-1, 10,853 m), the Mussau Trench (2.7±0.1×102 μmol O2 m-2 d-1, 7,011 m), and the New Britain Trench (6.0±0.1×102 μmol O2 m-2 d-1, 8,225 m). Combined with the analyses of total organic Carbon (TOC) and δ13C of TOC in the sediments and previously published in-situ O2 microprofiles from hadal settings, we suggest that hadal benthic Carbon Mineralization partly is governed by the surface production but also is linked to the distance from land. Therefore, we highlight that terrestrial organic matter can be of importance in sustaining benthic communities in some hadal settings.
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Impacts of increasing salinity and inundation on rates and pathways of organic Carbon Mineralization in tidal wetlands: a review
Hydrobiologia, 2017Co-Authors: Min Luo, Jiafang Huang, Wenfeng Zhu, Chuan TongAbstract:To improve our understanding of the Carbon cycling response to imminent sea-level rise and saltwater intrusions, we review the existing literature on the likely effects of the increasing salinity and inundation on organic Carbon Mineralization in tidal wetlands. Enhanced salinity and inundation will reduce the pool of the organic Carbon substrate, but may expand that of microbes with strong capacities for Carbon metabolism. Sulfate availability increases with the increasing salinity, while availability of other electron acceptors, e.g., oxygen, nitrate, ferric oxides, and Carbon dioxide, could transiently increase but would ultimately fall with the increasing salinity and inundation. The changing electron acceptor pattern may result in microbial sulfate reduction predominating over other Carbon Mineralization pathways. Data derived from natural salinity and inundation gradients suggest clear negative effects of salinity and inundation on production rates or emission fluxes of Carbon dioxide and methane. However, results for brackish wetlands are conflicting, probably due to their unique geographic location. Salinity and inundation exert their influence on organic Carbon Mineralization through sulfate enrichment, elevating ionic and osmotic stress and decreasing oxygen concentrations and redox conditions, among other biogeochemical changes. Future studies should address the combined effects of salinity and inundation on Carbon biogeochemistry in low-level salinity tidal wetlands.
Volker Brüchert - One of the best experts on this subject based on the ideXlab platform.
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Carbon Mineralization in Laptev and East Siberian sea shelf and slope sediment
Biogeosciences, 2018Co-Authors: Volker Brüchert, Lisa Bröder, Joanna E. Sawicka, Tommaso Tesi, Samantha P. Joye, Xiaole Sun, Igor Semiletov, Vladimir A. SamarkinAbstract:Abstract. The Siberian Arctic Sea shelf and slope is a key region for the degradation of terrestrial organic material transported from the organic-Carbon-rich permafrost regions of Siberia. We report on sediment Carbon Mineralization rates based on O 2 microelectrode profiling; intact sediment core incubations; 35 S-sulfate tracer experiments; pore-water dissolved inorganic Carbon (DIC); δ13 C DIC ; and iron, manganese, and ammonium concentrations from 20 shelf and slope stations. This data set provides a spatial overview of sediment Carbon Mineralization rates and pathways over large parts of the outer Laptev and East Siberian Arctic shelf and slope and allows us to assess degradation rates and efficiency of Carbon burial in these sediments. Rates of oxygen uptake and iron and manganese reduction were comparable to temperate shelf and slope environments, but bacterial sulfate reduction rates were comparatively low. In the topmost 50 cm of sediment, aerobic Carbon Mineralization dominated degradation and comprised on average 84 % of the depth-integrated Carbon Mineralization. Oxygen uptake rates and anaerobic Carbon Mineralization rates were higher in the eastern East Siberian Sea shelf compared to the Laptev Sea shelf. DIC ∕ NH 4 + ratios in pore waters and the stable Carbon isotope composition of remineralized DIC indicated that the degraded organic matter on the Siberian shelf and slope was a mixture of marine and terrestrial organic matter. Based on dual end-member calculations, the terrestrial organic Carbon contribution varied between 32 and 36 %, with a higher contribution in the Laptev Sea than in the East Siberian Sea. Extrapolation of the measured degradation rates using isotope end-member apportionment over the outer shelf of the Laptev and East Siberian seas suggests that about 16 Tg C yr −1 is respired in the outer shelf seafloor sediment. Of the organic matter buried below the oxygen penetration depth, between 0.6 and 1.3 Tg C yr −1 is degraded by anaerobic processes, with a terrestrial organic Carbon contribution ranging between 0.3 and 0.5 Tg yr −1 .
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Carbon Mineralization in Laptev and East Siberian Sea shelf and slope sediment
2017Co-Authors: Volker Brüchert, Lisa Bröder, Joanna E. Sawicka, Tommaso Tesi, Samantha P. Joye, Xiaole Sun, Igor Semiletov, Vladimir A. SamarkinAbstract:Abstract. The Siberian Arctic Sea shelf and slope is a key region for the degradation of terrestrial organic material transported from the organic Carbon-rich permafrost regions of Siberia. We report on sediment Carbon Mineralization rates based on O2 microelectrode profiling, intact sediment core incubations, 35S-sulfate tracer experiments, porewater dissolved inorganic Carbon (DIC), δ13CDIC, and iron, manganese, and ammonium concentrations from 20 shelf and slope stations. This data set provides a spatial overview of sediment Carbon Mineralization rates and pathways over large parts of the outer Laptev and East Siberian Arctic shelf and slope, and allowed us to assess degradation rates and efficiency of Carbon burial in these sediments. Rates of oxygen uptake and iron and manganese reduction were comparable to temperate shelf and slope environments, but bacterial sulfate reduction rates were comparatively low. In the topmost 20 to 50 cm of sediment, aerobic Carbon Mineralization dominated degradation and comprised on average 82 % of the depth-integrated Carbon Mineralization. Oxygen uptake rates and 35S-sulfate reduction rates were higher in the eastern East Siberian Sea shelf compared to the Laptev Sea shelf. DIC/NH4+ ratios in porewaters and the stable Carbon isotope composition of remineralized DIC indicated that the degraded organic matter on the Siberian shelf and slope was a mixture of marine and terrestrial organic matter. Based on dual end member calculations, the terrestrial organic Carbon contribution varied between 32 % and 36 %, with a higher contribution in the Laptev Sea than in the East Siberian Sea. Extrapolation of the measured degradation rates using isotope end member apportionment over the outer shelf of the Laptev and East Siberian Sea suggests that about 16 Tg C per year are respired in the outer shelf sea floor sediment. Of the organic matter buried below the oxygen penetration depth, between 0.6 and 1.3 Tg C per year are degraded by anaerobic processes, with a terrestrial organic Carbon contribution ranging between 0.3 and 0.5 Tg per year.
Greeshma Gadikota - One of the best experts on this subject based on the ideXlab platform.
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Carbon Mineralization pathways for Carbon capture, storage and utilization
Communications Chemistry, 2021Co-Authors: Greeshma GadikotaAbstract:Carbon Mineralization is a versatile and thermodynamically downhill process that can be harnessed for capturing, storing, and utilizing CO2 to synthesize products with enhanced properties. Here the author discusses the advances in and challenges of Carbon Mineralization, and concludes that tuning the chemical interactions involved will allow us to unlock its potential for advancing low Carbon energy and resource conversion pathways.
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Multiphase Carbon Mineralization for the reactive separation of CO_2 and directed synthesis of H_2
Nature Reviews Chemistry, 2020Co-Authors: Greeshma GadikotaAbstract:The water-gas shift reaction converts CO and H_2O into H_2 and CO_2, and reactive separation of the latter optimizes H_2 production. This Review describes how alkaline Ca and Mg compounds trap CO_2 to afford Carbonates as part of Carbon Mineralization. There is a need to capture, convert and store CO_2 by atom-efficient and energy-efficient pathways that use as few process configurations as possible. This need has motivated studies into multiphase reaction chemistries and this Review describes two such approaches in the context of Carbon Mineralization. The first approach uses aqueous alkaline solutions containing amine nucleophiles that capture CO_2 and eventually convert it into calcium and magnesium Carbonates, thereby regenerating the nucleophiles. Gas–liquid–solid and liquid–solid configurations of these reactions are explored. The second approach combines silicates such as CaSiO_3 or Mg_2SiO_4 with CO and H_2O from the water-gas shift reaction to give H_2 and calcium or magnesium Carbonates. Coupling Carbonate formation to the water-gas shift reaction shifts the latter equilibrium to afford more H_2 as part of a single-step catalytic approach to Carbon Mineralization. These pathways exploit the vast abundance of alkaline resources, including naturally occurring silicates and alkaline industrial residues. However, simple stoichiometries belie the complex, multiphase nature of the reactions, predictive control of which presents a scientific opportunity and challenge. This Review describes this multiphase chemistry and the knowledge gaps that need to be addressed to achieve ‘step-change’ advancements in the reactive separation of CO_2 by Carbon Mineralization.
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In situ Carbon Mineralization in ultramafic rocks: Natural processes and possible engineered methods
Energy Procedia, 2018Co-Authors: Peter B. Kelemen, Greeshma Gadikota, Roger D. Aines, E. Bennett, Sally M. Benson, E. Carter, J. A. Coggon, J. C. De Obeso, Owen Evans, G. M. DippleAbstract:Abstract In this invited review, we summarize the main results of ongoing research on “in situ” Carbon Mineralization in ultramafic rocks, including outcrop studies in Oman (e.g., [1, 2]), investigation of Carbon mass transfer in subduction zones from the Oman Drilling Project (e.g., [3-7]), laboratory investigations (e.g., [8-12]) and numerical modeling (e.g., [13-17]) of the pressure of crystallization and reaction-driven cracking, and assessment of the rate, cost and capacity of various proposed methods for engineered Carbon Mineralization [18, 19].
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Chemo-morphological coupling during serpentine heat treatment for Carbon Mineralization
Fuel, 2018Co-Authors: Meishen Liu, Greeshma GadikotaAbstract:Abstract One of the safest and permanent routes for potentially capturing and storing CO2 is via Carbon Mineralization which involves converting CO2 into environmentally benign and thermodynamically stable calcium and magnesium Carbonates. One of the most abundant Mg-bearing minerals in the world suitable for Carbon Mineralization is serpentine (Mg3Si2O5(OH)4). To enhance the reactivity of serpentine with CO2, dehydroxylation by heating to temperatures in the range of 600 °C–700 °C was proposed. To establish a fundamental structural and morphological basis for the enhanced reactivity of serpentine (e.g. lizardite) on heating to temperatures in this range, in-operando synchrotron multi-scale X-ray scattering measurements were performed, with complementary analyses of the changes in the porosity, particle size, and surface morphology. The detailed transformation of lamellar serpentine to a pseudo-amorphous state on heating to temperatures in the range of 600 °C–700 °C, and the subsequent conversion to denser crystalline phases such as Al2.35Si0.64O4.82 (mullite), SiO2 (cristobalite), Mg2SiO4 (forsterite), and Fe0.3Mg0.7(SiO3) (enstatite) was determined from the wide and small angle X-ray scattering measurements. Increasing roughness of the pore-solid interface on heating to 700 °C followed by enhanced smoothness due to the formation of crystalline phases at higher temperatures was established from the combined ultra small and small angle X-ray scattering measurements. The transformation of lamellar lizardite to its pseudo-amorphous state corresponded to an increase in the porosity and surface area, while the formation of crystalline phases reduced the porosity and surface area while increasing the particle size.
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Experimental Design and Data Analysis for Accurate Estimation of Reaction Kinetics and Conversion for Carbon Mineralization
Industrial & Engineering Chemistry Research, 2014Co-Authors: Greeshma Gadikota, Edward J. Swanson, Huangjing Zhao, Ah-hyung Alissa ParkAbstract:Silicate minerals such as olivine (Mg2SiO4) and serpentine [Mg3(OH)4(Si3O5)] can react with CO2 to form mineral Carbonates to permanently store CO2. Despite significant advancements in Carbon Mineralization, major discrepancies in the reported kinetics exist because of inconsistencies among various experimental methodologies, the heterogeneity and aging of the minerals, and inadequate fast kinetics and morphological data to probe the reaction mechanisms. In this work, it was found that aged and freshly ground olivine produce very different Carbonation yields. A new mineral cleaning protocol to remove fines (