Carbon monoxide rich methanation kinetics on supported rhodium and nickel catalysts

Technical Report · Tue Aug 01 00:00:00 EDT 1989

DOI:https://doi.org/10.2172/5622217· OSTI ID:5622217

Keehan, D.; Richardson, J. T. ^[1]

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1. Houston Univ., TX (USA). Dept. of Chemical Engineering

Utilization of CO{sub 2} reforming of methane in a solar-based chemical energy transmission system depends upon the development of suitable catalysts for the endothermic and exothermic reactions. Reforming of methane produces hydrogen and carbon monoxide at a ratio of about one, thus requiring the methanation reaction on the other side of the closed-loop chemical energy system to use this feed. H{sub 2}/CO ratios lower than three favor formation of carbon with industrial methanation catalysts. Preliminary tests of methanation with rhodium and nickel catalysts produced two, 0.5% Rh/Al{sub 2}O{sub 3} and 70% Ni/Al{sub 2}O{sub 3}, for further study. Kinetic experiments were conducted in an isothermal continuous-stirred tank reactor constructed of a copper alloy, which prevented carbon formation on reactor parts. These experiments were performed on pelleted 0.5% Rh/Al{sub 2}O{sub 3} in the 400 to 500{degrees}C range and pelleted 70% Ni/Al{sub 2}O{sub 3} in the 300 to 500{degrees}C range. In most experiments, steam was added to the reactor feed to inhibit carbon formation. Langmuir-Hinshelwood expressions were fitted to experimental data for both catalysts and are suitable for reactor design purposes. Lifetime studies, at high CO conversion, were run for both catalysts. The 0.5% Rh/Al{sub 2}O{sub 3} resists carbon formation very well and is recommended for application at temperatures above 400{degrees}C. The 70% Ni/Al{sub 2}O{sub 3} has a high carbon resistance at temperatures below 350{degrees}C and is suitable for application from 300 to 350{degrees}C. 39 refs., 99 figs.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Houston Univ., TX (USA). Dept. of Chemical Engineering
• Sponsoring Organization: DOE/CE
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5622217
• Report Number(s): SAND-88-7149; ON: DE90000898
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
METHANATION
CHEMICAL REACTION KINETICS
NICKEL
CATALYTIC EFFECTS
RHODIUM
ALUMINIUM OXIDES
CARBON MONOXIDE
CHEMICAL REACTORS
PARTIAL PRESSURE
SOLAR EQUIPMENT
STEAM
ALUMINIUM COMPOUNDS
CARBON COMPOUNDS
CARBON OXIDES
CHALCOGENIDES
CHEMICAL REACTIONS
ELEMENTS
EQUIPMENT
KINETICS
METALS
OXIDES
OXYGEN COMPOUNDS
PLATINUM METALS
REACTION KINETICS
TRANSITION ELEMENTS
CSP
Concentrating Solar Power
140505* - Solar Energy Conversion- Photochemical
Photobiological
& Thermochemical Conversion- (1980-)