Comments on “Catalyst Temperature Oscillations during Partial Oxidation of Methane”

Cohn, Jesse

doi:10.1021/ie9808312

Cited by 10 publications

(5 citation statements)

References 3 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The complexity of the reaction pathways involved in the oxidation of methane can result in oscillatory kinetics under certain circum-stances. Such oscillations have been observed over palladium catalysts [1][2][3][4], and supported nickel catalysts [5][6][7]. It has been observed in our earlier study that chromel/alumel thermocouple wires and nickels wires can also catalyse the methane/oxygen reaction and result in rate oscillations [8].…”

Section: Introductionsupporting

confidence: 59%

Oscillatory behaviour during the oxidation of methane over palladium metal catalysts

Zhang

Lee

Mingos

et al. 2003

Applied Catalysis A: General

View full text Add to dashboard Cite

Oscillatory reactions over palladium foil and wire catalysts during the oxidation of methane have been investigated over a wide range of reaction temperatures and argon/methane/oxygen feed gas compositions. Characterisation of the catalyst has also been carried out using scanning electron microscopy (SEM) techniques, which revealed the presence of a porous surface. This suggested that the metal surface has undergone a change since the reaction commenced, and using X-ray powder diffraction (XRD) techniques the palladium phase was shown to be the dominant phase present. Hysteresis phenomena were observed in the activity of the reaction as the temperature was cycled up and down, showing that the metal surface was continually changing throughout the reaction. The activation energies of the reaction during the high reactivity mode, PdO, and low reactivity mode, Pd, were also calculated. Oscillation rates were observed to depend on the dominant surface. Oscillations were frequent when the high reactivity mode was dominant while the activation energy of this mode was found to be low. When the low reactivity mode was dominant, the oscillations were slower and the activation energy was three times larger. The results obtained imply that the behaviour of the palladium surface, switching back and forth from the reduced state to the oxidised state, is responsible for the oscillatory behaviour seen in this system.

show abstract

Section: Introductionsupporting

confidence: 59%

Oscillatory behaviour during the oxidation of methane over palladium metal catalysts

Zhang

Lee

Mingos

et al. 2003

Applied Catalysis A: General

View full text Add to dashboard Cite

show abstract

“…Such oscillations have been observed over palladium catalysts [24][25][26][27], and supported nickel catalysts [11,28,29]. There has also been a recent report [30] of oscillations occurring over an Nd 2 O 3 /MgO catalyst containing an exposed chromel-alumel thermocouple.…”

Section: Introductionmentioning

confidence: 86%

Untitled

Zhang¹,

Mingos²,

Hayward³

2001

Catalysis Letters

View full text Add to dashboard Cite

show abstract

“…Such oscillations have been observed over palladium catalysts [9±12] and supported nickel catalysts [3,13,14]. There has also been a report [15] of oscillations occurring over an Nd 2 O 3 /MgO catalyst containing an exposed chromelalumel thermocouple.…”

Section: Introductionmentioning

confidence: 88%

Untitled

2002

View full text Add to dashboard Cite

The study of the partial oxidation of methane over nickel foils has been carried out over a wide range of reactor temperatures (748± 930 8C) and feed-gas compositions (Ar/CH 4 /O 2 ), ranging from 30 : 29 : 1 to 30 : 12 : 18 cm 3 min ÿ1 at atmospheric pressure. The product formation shows pronounced oscillations. A modi®ed thermocouple was designed to measure the temperature while the interposed nickel foil worked as a catalyst. The oscillations have been attributed to the cyclic reduction and oxidation of the nickel surface in the speci®c reaction environment at elevated temperatures.

show abstract

Comments on “Catalyst Temperature Oscillations during Partial Oxidation of Methane”

Cited by 10 publications

References 3 publications

Oscillatory behaviour during the oxidation of methane over palladium metal catalysts

Oscillatory behaviour during the oxidation of methane over palladium metal catalysts

Untitled

Untitled

Contact Info

Product

Resources

About