IMPROVED METHANOL YIELD FROM METHANE OXIDATION IN A NONISOTHERMAL REACTOR

Partial oxidation of methane to methanol was carried out homogeneously in a non-isothermal reactor that contained a non-permselective membra ne. A tubular reactor was used with a smaller-diameter tubular membran e of 5 nm pore diameter alumina or 0.5 mu m pore diameter metal. The m embrane provided a uniform flow distribution and separated the hot rea ctor wall from a cooling tube located in the centre of the reactor. Th e cold region in the reactor rapidly quenched further reaction. The se lectivity for CH3OH formation at 4.6% conversion increased from 34 to 52% when quenching was used. The highest yield (selectivity times conv ersion) obtained was 3.8% at 55 MPa and 800 K. Methanol selectivity in creased with increasing pressure and decreased with increasing tempera ture, residence time and O-2 concentration. The combined selectivity t o partial oxidation products (CO, CH3OH, CH2O) was almost constant at 86%. Copyright (C) 1996 Elsevier Science Ltd.