Partial oxidation of methane to synthesis gas at very short contact times

Catalytic partial oxidation of methane has been studied over Pt, Pt/Rh, Pt/Ir and Pd gauze catalysts at contact times in the range 0.00021-0.00033 s. The experiments were carried out at 1 bar and 700-1100 degrees C using a single gauze in a quartz reactor heated in an electric furnace. The feed consisted of CH4, O-2 and inert (Ar) and with different ratios between CH4 and O-2. High selectivities to CO were observed at high temperatures. However, the selectivity to H-2 was always rather low (below 30% in most cases) at these conditions with incomplete conversion of O-2. Alloying the Pt gauze with Ph improves the selectivity to synthesis gas as well as the time on stream behaviour. The effect of the CH4/O-2 ratio depends on the gauze. The selectivity to synthesis gas decreased with increasing amount of O-2 on the Pt gauze whereas the opposite effect was observed on a Pt/Rh gauze. (C) 1998 Elsevier Science B.V. All rights reserved.