TUBE BUNDLE REACTOR FOR PRODUCING MALEIC ACID ANHYDRIDE

摘要

The invention relates to a system for producing maleic acid anhydride by means of heterogeneously catalyzed gas phase oxidation of an inlet flow, comprising hydrocarbons having at least (4) carbon atoms per molecule, comprising a reactor having a bundle of reaction tubes into which a solid catalyst is introduced, on which the exothermal reaction of the inlet flow with a gas flow containing oxygen takes place, and one or more pumps and one or more heat exchangers located outside of the reactor, by means of which a heat carrier made of a salt melt is carried, permeating the intermediate reaction space between the reaction tubes and absorbing reaction heat, the temperature of the salt melt being in the range of 350 to 480 °C, characterized in that the reaction tubes are made of an alloyed, heat-resistant steel comprising either at least 0.5 wt % chromium, or at least 0.25 wt % molybdenum, or at least 0.5 wt % chromium and at least 0.25 wt % molybdenum.