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Oxidative coupling of methane to C2+ hydrocarbons over a Zr/La/Sr catalyst was investigated in an atmospheric-pressure shallow fluidized-bed reactor (i.d. = 5 cm; H mf = 1.4−3.2 cm) at temperatures between 800 and 880 °C. The catalyst was mechanically and catalytically stable, but its fluidizability was limited; agglomeration and channeling occurred. The highest C2+ yield amounted to 18.0% (X CH 4 = 36.5%, S C 2+ = 49.4%) and 17.2% (X CH 4 = 36.6%, S C 2+ = 46.9%) for the diluted (p O 2 = 17 kPa, p CH 4 = 41.5 kPa, p N 2 = 41.5 kPa) and undiluted feed (p O 2 = 28 kPa, p CH 4 = 72 kPa), respectively. These yields are among the highest ones reported in the open literature for OCM in fluidized beds. In the whole investigated temperature range higher selectivities and yields were obtained upon reducing partial pressures of methane and oxygen but keeping their ratio constant (p CH 4 /p O 2 = 2.5). An increased gas velocity (from u/u mf = 6 to 10) or bed height (from 1.4 to 3.2 cm) resulted in a drop of C2+ selectivity.

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