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Abstract In this work, a new type of multifunctional materials (MFMs) called self‐regenerative Ni‐doped CaTiO3/CaO is introduced for the integrated CO2capture and dry reforming of methane (ICCDRM). These materials consist of a catalytically active Ni‐doped CaTiO3and a CO2sorbent, CaO. The article proposes a concept where the Ni catalyst can be regenerated in situ, which is crucial for ICCDRM. Exsolved Ni nanoparticles are evenly distributed on the surface of CaTiO3under H2or CH4, and are re‐dispersed back into the CaTiO3lattice under CO2. The Ni‐doped CaTiO3/CaO MFMs show stable CO2capture capacity and syngas productivity for 30 cycles of ICCDRM. The presence of CaTiO3between CaO grains prevents CaO/CaCO3thermal sintering during carbonation and decarbonation. Moreover, the strong interaction of CaTiO3with exsolved Ni mitigates severe accumulation of coke deposition. This concept can be useful for developing MFMs with improved properties that can advance integrated carbon capture and conversion.
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CO 2 Capture and Direct Air CO 2 Capture Followed by Integrated Conversion to Methane Assisted by Metal Hydroxides and a Ru/Al 2 O 3 Catalyst
Abstract Rising CO2levels are leading to an increase in atmospheric greenhouse gas effect. Hydroxide salts have previously been shown to be promising reagents for capturing CO2. Utilizing a 5 %Ru/Al2O3catalyst, the carbonates obtained through CO2capture can then be hydrogenated to methane. This conversion occurs at relatively mild temperatures from 200 °C to 250 °C under 40 to 70 bar H2with yields of up to 100 %. Natural sources of calcium carbonate, like eggshells and seashells, can also be partially converted to methane. The direct air CO2capture and conversion of CO2to methane was achieved as well in quantitative yields.
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- Award ID(s):
- 2018740
- PAR ID:
- 10470966
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- ChemCatChem
- Volume:
- 15
- Issue:
- 23
- ISSN:
- 1867-3880
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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