Catalyst composition for producing (meth)acrolein by gas phase olefin oxidation, contains active inorganic catalyst material and superparamagnetic particles for controlling oxygen supply

摘要

A new catalyst composition (I) comprises (a) active inorganic catalyst material and (b) superparamagnetic (SPM) particles, consisting of magnetite nanoparticles encapsulated with silicon dioxide or with (a). The SPM particles have average primary particle size 10-100 mu m and are bonded to give porous shaped article. The average size of the magnetite particles is 3-50 nm. An independent claim is included for the catalytic gas-phase oxidation of propene or isobutene to (meth)acrolein in presence of oxygen, where (a) the oxygen is supplied to the oxidation reaction chamber through a shaped article containing or consisting of the catalyst (I) and (b) the supply of oxygen to the reaction chamber is controlled by generating and removing a magnetic field in (I) parallel to the oxygen passage direction through (I).