Patent DE-102007019597-A1 (DE)
Title: Partial gas phase oxidation of acrolein to acrylic acid or methacrolein to methacrylic acid, useful e.g. as monomer to prepare polymers, comprises using a tube bundle reactor in reaction tube of a vertically arranged reaction tubes
Inventor: HAMMON ULRICH
IPC: C07C57/055
Filed: 2007-04-24
Abstract: Process for implementing a heterogeneously catalyzed partial gas phase oxidation of acrolein to acrylic acid or methacrolein to methacrylic acid in a solid catalyst bed comprises using a tube bundle reactor in reaction tube of a vertically arranged bundle of reaction tubes (9), which are closed by a reactor jacket; where: the both ends of the individual reaction tubes are open and each reaction tubes terminate with its upper end in a passage of a top tube plate sealed above in reactor jacket and with its lower end in a passage of a down tube plate (5) sealed below in reactor jacket. Process for implementing a heterogeneously catalyzed partial gas phase oxidation of acrolein to acrylic acid or methacrolein to methacrylic acid in a solid catalyst bed comprises using a tube bundle reactor in reaction tube of a vertically arranged bundle of reaction tubes (9), which are closed by a reactor jacket; where: the both ends of the individual reaction tubes are open and each reaction tubes terminate with its upper end in a passage of a top tube plate sealed above in reactor jacket and with its lower end in a passage of a down tube plate (5) sealed below in reactor jacket; the exterior of the reaction tubes, the top and the down tube plate, and the reactor jacket differentiate conjointly to the reaction tube surrounding chamber, and each of the two tube plates is spanned by at least a reactor cover (6) having an opening, with which, in order to set start-up in several respects, to the reaction tubes of the tube bundle reactor, at least an opening (3) in one of the both reactor covers supplies a reaction gas inlet mixture (1) containing >= 3 vol.% of acrolein or methacrolein and additionally molecular oxygen; at least an opening of the other reactor cover discharges by partial gas phase oxidation of the acrolein to acrylic acid or methacrolein to methacrylic acid, where the passage of the product gas mixture (2) containing acrylic acid or methacrylic acid results in the solid catalyst bed, which is present in the reaction tubes; at least a liquid heat exchange medium is supplied on the jacket side of the tube bundle reactor around the reaction tubes in such a manner that each of the two surfaces, which turned to each other, of the two tube plates is moistened by liquid heat exchange medium; the liquid heat exchange medium is inwardly introduced with a temperature T w(in) into the reaction tubes surrounding chamber and is outwardly emitted with the temperature T w(out) from the reaction tubes surrounding chamber; the temperature T w(in) of the liquid heat exchange medium, which moistens the tube plate spanned by the tube cover having the at least one opening, is at least 290[deg] C; the reaction gas inflow mixture entering into the opening has a temperature of = 285[deg] C, and the temperature of the surface of the reactor plate (4) turned to the reactor cover having at least an opening, has a value of = 285[deg] C.