Device and method for carrying out heterogeneously catalysed gas phase reactions with heat tonality

Abstract

Apparatus for substantially isothermal operation of a heterogeneously catalyzed gas phase reaction involving a pronounced exotherm comprises at least one reactor space ( 101 ) having an inlet ( 131, 141 ) and an outlet ( 143 ), wherein the reactor space is bounded by heat-removing walls which are spaced apart substantially uniformly at a distance of ≦30 mm along the main flow axis of a reaction gas, the reactor space is fitted with catalyst-coated tapes ( 120, 132 ), the tapes are flexible and pervious to the reaction gas in all spatial directions and have a surface to volume ratio of 50 to 5000 m 2 /m 3 and also a good thermal conductivity, the reaction gas flows through the reactor space at a velocity of ≧200 m 3 per m 2 of frontal area per hour, and a heat exchange medium flows on that side of the reactor wall which is remote from the reactor space.

We claim:  
     
         1 . Apparatus for substantially isothermal operation of a heterogeneously catalyzed gas phase reaction involving a pronounced exotherm, comprising at least one reactor space ( 101 ) having an inlet ( 131 ,  141 ) and an outlet ( 143 ), wherein 
 the reactor space is bounded by heat-removing walls which are spaced apart substantially uniformly at a distance of ≦30 mm along the main flow axis of a reaction gas,    the reactor space is fitted with catalyst-coated tapes ( 120 ,  132 ),    the tapes are flexible and pervious to the reaction gas in all spatial directions and have a surface to volume ratio of 50 to 5000 m 2 /m 3  and also a good thermal conductivity,    the reaction gas flows through the reactor space at a velocity of ≧200 m 3  per m 2  of frontal area per hour, and    a heat exchange medium flows on that side of the reactor wall which is remote from the reactor space.    
     
     
         2 . Apparatus as claimed in  claim 1 , wherein the reactor space is formed by the gap of a heat exchanger.  
     
     
         3 . Apparatus as claimed in  claim 1  or  2 , wherein the reactor space is formed by the gap of a spiral type, plate type or annular gap heat exchanger.  
     
     
         4 . Apparatus as claimed in any of  claims 1  to  3 , wherein the tapes are formed from metals, asbestos substitutes, glass fibers, carbon fibers and/or plastics.  
     
     
         5 . Apparatus as claimed in  claim 4 , wherein the tapes ( 120 ,  132 ) are formed by a woven metal fabric or by a loop-drawingly knitted metal fabric.  
     
     
         6 . Apparatus as claimed in any of  claims 1  to  5 , wherein the sequence of voids, wires or threads in the reactor space is ruleless as a consequence of the random orientation of the tapes ( 120 ,  132 ) with regard to the main flow axis of the reaction gas.  
     
     
         7 . Apparatus as claimed in any of  claims 1  to  6 , wherein the walls in the reactor space are spaced from 0.5 to 30 mm, preferably from 1 to 20 mm, particularly preferably from 1.5 to 10 mm, apart.  
     
     
         8 . The use of apparatus as claimed in any of  claims 1  to  7  in a process for oxidizing alcohols to aldehydes in the gas phase.  
     
     
         9 . The use of apparatus as claimed in any of  claims 1  to  7  in a process for oxidizing 3-methyl-3-buten-1-ol to 3-methyl-2-butenal in the gas phase as per equation I