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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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Direct Hydrogenolysis of Cellulose to Methane Utilizing Rare‐Earth Promoted Nickel Catalysts
Abstract Cellulose is one of the main components of plant matter, which makes it a viable target for biomass conversion to fuels. The direct conversion of cellulose to methane utilizing nickel‐based catalysts often has challenges associated with it. Carbon agglomeration creating nickel‐carbon nanoparticles deactivating catalytic hydrogenation of cellulose has been well reported. Utilizing rare‐earth metals as promoters increases the conversion of cellulose to methane, albeit with deactivation of the catalyst in the form of nickel‐rare‐earth‐carbon nanoparticles. Adding an additional zinc metal promoter eliminates the carbon agglomeration and allows for increased methane yields. Herein, we report an 81 % methane yield from cellulose in 48 hours utilizing a Ni/Zn/Y/Al2O3catalyst at 225 °C and under 50 bar H2pressure.
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- Award ID(s):
- 2018740
- PAR ID:
- 10419197
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Israel Journal of Chemistry
- Volume:
- 63
- Issue:
- 7-8
- ISSN:
- 0021-2148
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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