Catalytic partial oxidation of methane to synthesis gas in a pilot-plant-scale spouted-bed reactor

The catalytic partial oxidation (CPO) of methane to synthesis gas was inves tigated in a conical spouted-bed reactor unit by using Ni/La/Al2O3 catalyst s at pressures of 1-10bar, temperatures up to 1050 degrees C, methane-to-ox ygen ratios of 1.6-2.5 and 0-40% N-2 dilution. The experimental results dem onstrated that the spouted bed contacting mode is capable of dissipating th e strong exotherm of the CPO reaction via particle circulation through the spout, annulus and fountain regions. The catalysts retained their activity and stability over prolonged periods of time-on-stream, indicating good bal ance between the oxidation and reduction cycles. However, lower than equili brium methane conversions and syngas yields were observed because of heat l osses in the freeboard. The results provide convincing evidence that near e quilibrium conversions can be obtained by optimization of the freeboard des ign, Ni catalyst content, bed depth, and particle size. (C) 1999 Elsevier S cience Ltd. All rights reserved.