Modeling and Simulation of a Riser-Reactor for Partial Oxidation of n-C4 to MA and a Regenerator Reactor to re-Oxidize of the VPO Catalyst

The selective oxidation of hydrocarbons in Fixed-Bed or Fluidized-Bed reactors is conventionally characterized by the simultaneous presence of oxygen gas and hydrocarbon vapor at the active sites of the catalyst. But in order to increase the selectivity it has been suggested to separate the reaction into two phases; a first step where the catalyst chemisorbs oxygen and a second step, where the oxidized catalyst reacts with the hydrocarbons. Partial oxidation of n-butane to maleic anhydride (MA) is the most important example of these processes. N-butane oxidation step has been carried out at a riser–reactor and re-oxidation of VPO catalyst has been carried out at a similar reactor, and because of high circulation rate of catalyst particles (between n-butane oxidation and oxygen loading on catalyst particles steps in presence two step process) high attrition resistance of catalyst is necessary.In the presence work, the oxidation of n-butane to MA and re-oxidation of catalyst separately have been modeled. Also effect of modeling parameters on output results has been studied.