Supported molten-salt membranes for carbon dioxide permeation

Photocatalytic processes to convert CO2 to useful products including CO and HCOOH are of particular interest as a means to harvest the power of the sun for sustainable energy applications. Herein, we report the photocatalytic reduction of CO2 using iron-based catalysts and visible light generating varying ratios of synthesis gas.

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A Solar Gas Turbine Cycle With Super-Critical Carbon Dioxide as a Working Fluid

Volume 4: Cycle Innovations; Electric Power; Industrial and Cogeneration; Manufacturing Materials and Metallurgy ◽

10.1115/gt2006-90864 ◽

2006 ◽

Cited By ~ 4

Author(s):

Motoaki Utamura ◽

Yutaka Tamaura

Keyword(s):

Carbon Dioxide ◽

Heat Exchanger ◽

Molten Salt ◽

Gas Turbine ◽

Thermal Power ◽

Working Fluid ◽

Regenerative Heat ◽

Operation Conditions ◽

Gas Turbine Cycle ◽

Cycle Efficiency

Solar thermal power generation system equipped with molten salt thermal storage offers continuous operation at a rated power independent of the variation of insolation. A gas turbine cycle for solar applications is studied which works in a moderate temperature range (600–850K) where molten salt stays as liquid stably. It is found that a closed cycle with super-critical state of carbon dioxide as a working fluid is a promising candidate for solar application. The cycle featured in smaller compressor work would achieve high cycle efficiency if cycle configuration and operation conditions are chosen properly. The temperature effectiveness of a regenerative heat exchanger is shown to govern the efficiency. Under the condition of 98% temperature effectiveness, the regenerative cycle with pre- and inter-cooling provides cycle efficiency of as much as 47%. A novel heat exchanger design to realize such a high temperature effectiveness is also presented.

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Supercritical Carbon Dioxide Power Cycle Configurations for Use in Concentrating Solar Power Systems

Volume 5: Manufacturing Materials and Metallurgy; Marine; Microturbines and Small Turbomachinery; Supercritical CO2 Power Cycles ◽

10.1115/gt2012-68932 ◽

2012 ◽

Cited By ~ 49

Author(s):

Craig S. Turchi ◽

Zhiwen Ma ◽

John Dyreby

Keyword(s):

Carbon Dioxide ◽

Energy Storage ◽

Molten Salt ◽

Thermal Energy ◽

Thermal Energy Storage ◽

Solar Power ◽

Brayton Cycle ◽

Concentrating Solar Power ◽

Power Cycle ◽

Cycle Efficiency

Concentrating Solar Power (CSP) plants utilize oil, molten salt or steam as the heat transfer fluid (HTF) to transfer solar energy to the power block. These fluids have properties that limit plant performance; for example, the synthetic oil and molten salt have upper temperature limits of approximately 390°C and 565°C, respectively. While direct steam generation has been tested, it requires complex controls and has limited options for integration of thermal energy storage. Use of carbon dioxide as the HTF and power cycle working fluid offers the potential to increase thermal cycle efficiency while maintaining simplicity of operation and thermal storage options. Supercritical CO2 (s-CO2) operated in a closed-loop recompression Brayton cycle offers the potential of higher cycle efficiency versus superheated or supercritical steam cycles at temperatures relevant for CSP applications. Brayton-cycle systems using s-CO2 have smaller weight and volume, lower thermal mass, and less complex power blocks versus Rankine cycles due to the higher density of the fluid and simpler cycle design. Many s-CO2 Brayton power cycle configurations have been proposed and studied for nuclear applications; the most promising candidates include recompression, precompression, and partial cooling cycles. Three factors are important for incorporating s-CO2 into CSP plants: superior performance vs. steam Rankine cycles, ability to integrate thermal energy storage, and dry-cooling. This paper will present air-cooled s-CO2 cycle configurations specifically selected for a CSP application. The systems will consider 10-MW power blocks that are tower-mounted with an s-CO2 HTF and 100-MW, ground-mounted s-CO2 power blocks designed to receive molten salt HTF from a power tower.

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Electrochemical dissolution behavior of conductive TiCxO1–x solid solutions

Pure and Applied Chemistry ◽

10.1351/pac-con-09-10-39 ◽

2010 ◽

Vol 82 (8) ◽

pp. 1691-1699 ◽

Cited By ~ 23

Author(s):

Shuqiang Jiao ◽

Xiaohui Ning ◽

Kai Huang ◽

Hongmin Zhu

Keyword(s):

Carbon Dioxide ◽

Solid Solution ◽

Carbon Monoxide ◽

Molten Salt ◽

Solid Solutions ◽

Anode Materials ◽

Carbothermic Reduction ◽

Dissolution Behavior ◽

Electrochemical Dissolution ◽

Ion Species

Conductive TiCxO1–x solid solutions were prepared by carbothermic reduction of titanium dioxide. Studies were focused on the possibility of electrochemically dissolving TiCxO1–x in NaCl–KCl molten salt. The tail-gas from the anode was monitored during the electrolysis. It was discovered that carbon monoxide (CO) or carbon dioxide (CO2) gases were generated, with the process being dependent upon the consumption of the TiCxO1–x solid solution anode materials. Furthermore, a series of electrochemical methods was used to investigate the valence state of titanium ions dissolved into molten salt when electrolyzing TiCxO1–x solid solutions. A significant result was that titanium ion species dissolved from the TiCxO1–x solid solutions, and this is changed between Ti2+ and Ti3+ depending on the electrochemically dissolving potentials. The significant result discovered in this paper will be potentially beneficial in the preparation of high-purity titanium by electrorefining TiCxO1–x solid solutions.

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Recent Advances in Molten-Carbonate Membranes for Carbon Dioxide Separation: Focus on Material Selection, Geometry, and Surface Modification

The Scientific World JOURNAL ◽

10.1155/2021/1876875 ◽

2021 ◽

Vol 2021 ◽

pp. 1-22

Author(s):

Shabana Afzal ◽

Atif Khan

Keyword(s):

Carbon Dioxide ◽

Molten Salt ◽

Material Selection ◽

Ceramic Membranes ◽

Co2 Separation ◽

Molten Carbonate ◽

Carbon Dioxide Transport ◽

Carbon Dioxide Separation ◽

Support Materials ◽

Separation Membranes

Membranes for carbon dioxide permeation have been recognized as potential candidates for CO2 separation technology, particularly in the energy sector. Supported molten-salt membranes provide ionic routes to facilitate carbon dioxide transport across the membrane, permit the use of membrane at higher temperature, and offer selectivity based on ionic affinity of targeted compound. In this review, molten-carbonate ceramic membranes have been evaluated for CO2 separation. Various research studies regarding mechanisms of permeation, properties of molten salt, significance of material selection, geometry of support materials, and surface modifications have been assessed with reference to membrane stabilities and operational flux rates. In addition, the outcomes of permeation experiments, stability tests, selection of the compatible materials, and the role of interfacial reactions for membrane degradation have also been discussed. At the end, major challenges and possible solutions are highlighted along with future recommendations for fabricating efficient carbon dioxide separation membranes.

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Sustainable Conversion of Carbon Dioxide into Diverse Hydrocarbon Fuels via Molten Salt Electrolysis

ACS Sustainable Chemistry & Engineering ◽

10.1021/acssuschemeng.0c08209 ◽

2020 ◽

Vol 8 (51) ◽

pp. 19178-19188

Author(s):

Ossama Al-Juboori ◽

Farooq Sher ◽

Saba Rahman ◽

Tahir Rasheed ◽

George Z. Chen

Keyword(s):

Carbon Dioxide ◽

Molten Salt ◽

Hydrocarbon Fuels ◽

Molten Salt Electrolysis

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Methane dry reforming catalyst prepared by the co-deflagration of high-nitrogen energetic complexes

Journal of Materials Chemistry A ◽

10.1039/c8ta08343f ◽

2019 ◽

Vol 7 (1) ◽

pp. 141-149 ◽

Cited By ~ 7

Author(s):

Moran Dahan ◽

Eswaravara Komarala ◽

Ludmila Fadeev ◽

Ajay K. Chinnam ◽

Avital Shlomovich ◽

...

Keyword(s):

Carbon Dioxide ◽

Dry Reforming ◽

High Nitrogen ◽

Synthetic Fuels ◽

Methane Dry Reforming ◽

Energy Applications ◽

Reforming Catalyst

Methane dry reforming presents a unique opportunity to simultaneously consume both methane and carbon dioxide and generate from them clean-burning synthetic fuels for mobile energy applications.

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