公开(公告)号：EP1658258B1

公开(公告)日：2008-05-14

申请号：EP04740696.2

申请日：2004-07-06

Applicant: BASF SE

Inventor： DUDA, Mark ,  MACHHAMMER, Otto ,  WECK, Alexander

IPC: C07C51/215

CPC classification number: C07C51/215 ,  C07C57/145

Abstract: Disclosed is a method for producing maleic anhydride by means of heterogeneous catalytic gas phase oxidation of n-butane with gases containing oxygen on a catalyst comprising vanadium, phosphorus, and oxygen in a reactor unit at a temperature ranging between 350 and 500 °C, whereupon the obtained maleic anhydride is isolated while a gas flow is formed that contains unreacted n-butane and water, and at least some of the unreacted n-butane is recirculated to the reactor unit. According to the inventive method, an input flow having an n-butane concentration of 0.5 to 1.5 percent by volume and an oxygen concentration of 5 to 21 percent by volume is fed to the reactor unit while a pressure of 0.4 to 2 MPa abs is adjusted at the inlet of the reactor unit and 40 to 100 percent of the n-butane from the input flow are reacted per reactor cycle.