A METHOD FOR CARRYING OUT EXOTHERMAL CATALYTIC GAS PHASE RACTIONS

摘要

An exothermal catalytic gas phase reaction is conducted in a cooled reactor containing a bed of porous catalyst particles each having an outermost zone that has catalytic activity with respect to that reaction that is less than the catalytic activity of the remainder of the particle. Optionally, the pores in the outermost zone may contain a material catalytically active in a side- reaction. When the method is applied to methanation accompanied by a water gas reaction it is preferred to use, as the catalyst particles, particles comprising a porous support containing nickel and having copper in the outermost layer of each particle. Such catalysts are novel.