Patent ID: 7531147
Filing Date: 2009-05-12
Classification: B01J,C07C

Abstract:
1. A shell-and-tube reactor that may be used for fixed-bed catalytic partial oxidation, the reactor being characterized by including at least one reaction zone of a first-step reaction zone for mainly producing unsaturated aldehydes from olefins and a second-step reaction zone for mainly producing unsaturated acids from unsaturated aldehydes, wherein at least one reaction zone of the above reaction zones comprises two or more catalytic layers; each of the catalytic layers is packed with a formed product of catalyst that is different in pore density and/or pore size in a catalytically active component; and the pore density and/or pore size is controlled in such a manner that specific surface area of the catalytically active component increases from the inlet of the reactor to the outlet of the reactor.