ACROLEIN CATALYTIC OXIDATION PROCESS TO ACRYLIC ACID IN A GASEOUS PHASE

摘要

In the present invention, there is described a process for the catalytic gas-phase oxidation of acrolein to acrylic acid in a multiple contact tube fixed-bed reactor through whose space surrounding the contact tubes only one heat-exchange medium circuit is passed, at elevated temperature on catalytically active multimetal oxides with an acrolein conversion for a single pass and an acrylic acid formation selectivity, which comprises firstly passing the heat-exchange medium through the multiple contact tube fixed-bed reactor longitudinally, considered over the reaction container as a whole, to the contact tubes in co-current to the reaction-gas mixture and secondly superposing a transverse flow within the reaction container by means of an arrangement of successive baffles along the contact tubes which leaves passage cross sections free, so as to give a meandrous flow of the heat-exchange medium, seen in longitudinal section through the contact tube bundle, and setting the flow rate of the circulated heat-exchange medium so that its temperature rises by from 2 to 10 degC.