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Catalytic partial oxidation of CH4 to H2 over cobalt catalysts at moderate temperatures

Paper ID Volume ID Publish Year Pages File Format Full-Text
43358 45966 2007 13 PDF Available
Title
Catalytic partial oxidation of CH4 to H2 over cobalt catalysts at moderate temperatures
Abstract

Catalytic partial oxidation (CPO) of methane has been investigated over Co/Al2O3 catalysts with different metal (0.1 wt.% of Ni, Pt, Rh, Ru or Pd) and oxide (<4 wt.% Fe3O4/Cr2O3, La2O3, SnO2 or K2O) promoters. A comparison with Ni- and Fe-based catalysts was performed. Methane conversions and selectivities were determined in the temperature range 200–750 °C at atmospheric pressure in a continuous fixed-bed quartz reactor. The scope was to identify factors for control of product selectivity and investigate the potential of low temperature operation. The unpromoted 10 wt.% Co/Al2O3 catalyst showed stable steady-state performance at 650 °C in the gas hourly space velocity range 15–180 N l CH4/gcat h. Equilibrium behaviour was observed during ramping (−1 °C/min) until a sudden extinction occurred around 450 °C, seemingly coinciding with O2 breakthrough. Addition of 0.1 wt.% metal promoter, particularly Pt and Rh, caused the activity to be maintained to lower temperatures. While Rh maintained H2 formation, Pt promoted combustion at low temperatures. Addition of 0.1 wt.% Ni by co-impregnation promoted carbon formation and deactivation. Addition of surface oxides typically promoted instability, deactivation and combustion. While the performance of Ni catalysts was superior to Co catalysts at low temperatures, Fe-based catalysts showed combustion activity in the whole temperature range. A hydrogen yield according to equilibrium predictions seems to be the best possible achievement.

Graphical abstractCatalytic partial oxidation (CPO) of methane has been investigated over Co/Al2O3 catalysts with different metal (0.1 wt.% of Ni, Pt, Rh, Ru or Pd) and oxide (<4 wt.% Fe3O4/Cr2O3, La2O3, SnO2 or K2O) promoters. A comparison with Ni- and Fe-based catalysts was performed. Methane conversions and selectivities were determined in the temperature range 200–750 °C at atmospheric pressure in a continuous fixed-bed quartz reactor.Figure optionsDownload full-size imageDownload as PowerPoint slide

Keywords
Low temperature CPO; Methane; Hydrogen; Cobalt; Nickel
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Catalytic partial oxidation of CH4 to H2 over cobalt catalysts at moderate temperatures
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Publisher
Database: Elsevier - ScienceDirect
Journal: Applied Catalysis A: General - Volume 333, Issue 1, 3 December 2007, Pages 11–23
Authors
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Subjects
Physical Sciences and Engineering Chemical Engineering Catalysis
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Don't Miss Today's Special Offer
Price was $35.95
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Price after discount Only $4.95
100% Money Back Guarantee
Full-text PDF Download
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Any Questions? feel free to contact us