Kinetic features of the size effect in methane oxidation over Pt/γ-Al2O3 catalysts

Kinetics of simultaneous oxidation of CO‐CH4 over Pd‐K promoted NiCo2O4/γ‐Al2O3 catalyst

“…Yoon et al [4] Pt-Rh (1-1) Power law 160-200 66.1 Lin et al [5] Au/TiO 2 L-H 47-97 8.3-37.6 Bruk et al [6] Pd-Cu/g-Al 2 O 3 L-H 20-38 40 Guo et al [12] K-Hopcalite Power law 80-120 27.77 Singh and Madras [13] Co 3 O 4 -O Drift analysis 55-155 42.3 Lou et al [14] CuO- [7] Pd/g-Al 2 O 3 L-H 60-150 34.7 Zhu et al [8] PdO, Pd Power law 327-607; 660-720 30;125 Xin et al [9] PdO Power law 267-527 62.8 Pakharukov et al [10] Pt/ g-Al 2 O 3 L-H 356-500 65 Specchia et al [11] 2 % Pd-Ce x Zr 1-x O 2 MvK 380-500 31.9 Zedan et al [16] CuO/ g-Al 2 O 3 E-R 723-923 125 Veldsink et al [17] CVD-made Co 3 The kinetics of CH 4 oxidation over Co 3 O 4 thin films was investigated by Bahlawane [18] who proposed the MvK model best fitted the experimental data and the rate limiting step is reoxidation of lattice of the catalyst. The activation energies for oxidation of CH 4 with lattice oxygen and reoxidation of lattice are 48.2 and 48.7 kJ/mol respectively.…”

“…where [C i ] is the concentration of the reactant 'i' which can be calculated assuming a constant density system at low conversion in the present case using Equation (10).…”

“…It was reported that PdO is the active phase and the reaction followed pseudo‐first‐order with respect to CH 4 and the apparent activation energy of 62.8 kJ/mol. Recently, the significant change in the kinetics parameter by variation of the size of catalyst particles in the oxidation of CH 4 was reported by Pakharukov et al The order of CH 4 oxidation reaction over all the catalysts deviates from unity. The presence of CO 2 has no effect on the kinetic parameters, whereas water negatively affects the reaction.…”

“…There are several studies reported in the literature which explore the kinetics of CH 4 oxidation leading to power-law [8][9]23] and mechanistic investigations [10][11][16][17][18] over various catalysts. The power-law model is reported by limited investigators, [8][9]23] whereas mechanistic models such as Langmuir-Hinshelwood (LH), [10,18] Eley-Rideal (ER), [16] and Mars van Krevelen (MvK) [11,18] are widely investigated. Abbasi et al [25] studied power-law kinetics of CH 4 over thermally-aged Pt and steam-aged Pt-Pd catalysts using the intergral method of analysis of kinetic data.…”

“…The catalytic combustion of CO and CH 4 has been investigated separately over noble metals, transition metals, and mixed metal oxides . Among noble metals Pd and Pt showed promising activity of the combustion of such a gaseous mixture.…”