Methane coupling by membrane reactor. Quarterly technical progress report, June 25--September 24, 1997

Abstract

A new reactor module was constructed as a porous membrane reactor or radial flow reactor for the study of methane oxidative coupling. A Mn-W-Na/SiO{sub 2} catalyst was prepared by the slurry mixing method and its catalytic activity was evaluated in a porous alumina membrane reactor. Experimental results showed that the Mn-W-Na/SiO{sub 2} catalyst calcined at 900 C was not stable during methane oxidative coupling. After 1,050 C calcination the catalyst became stable, however its activity was not as good as the one prepared by incipient wetness impregnation. The dense membrane tube obtained from Eltron Research Inc. was tested in a membrane reactor for the catalytic oxidative coupling of methane. The Mn-W-Na/SiO{sub 2} catalyst prepared by the incipient wetness impregnation method was packed inside the membrane tube. The initial oxygen flux was 0.02 cc/cm{sup 2}-min. It increased to 0.34 cc/cm{sup 2}-min after reaction and remained unchanged during a period of 31 days on stream. In a temperature range of 688 C to 977 C, the increase in oxygen flux with temperature obeyed the Arrhenius law. The C{sub 2} yield was about 10% at a methane conversion of 20%. The yield of the membrane reactor with Eltron membrane tube was higher than that with the Argonne membrane tube.