Patent ID: 8133445

Claim:
A chamber in which a chemical reaction is performed in the presence of catalyst and reagents, comprising: At least one catalytic tube ( 10 ) comprising therein an internal evacuation tube ( 12 ) for evacuating exhaust gas to the outside, catalyst ( 13 ) being arranged between the internal evacuation tube ( 12 ) and an inside surface of the catalytic tube ( 10 ), Means for introducing reagents ( 15 ) located in the upper portion of the chamber ( 1 ), Means for introducing the catalyst ( 16 ) located in the upper portion of the chamber ( 1 ), Means for heating the catalytic tube ( 10 ) arranged in the lower portion of the chamber ( 1 ), and in which the catalytic tube ( 10 ) comprises, in its upper portion above the catalyst ( 13 ), a reduced cross section of passage section ( 17 ) for the reagents for promoting heat exchange between the reagents and the resultant gas.