PROCESS FOR PRODUCING SHORT-CHAIN OLEFINS FROM OXYGENATES

摘要

There is proposed a process for producing short-chain olefins by conversion of oxygenates in a multi-stage fixed-bed reactor (OTO reactor) with reaction zones each operated adiabatically, in which the individual stages or reaction zones are covered with beds of a granular, form-selective zeolite catalyst which previously has been subjected to a steam pretreatment in an external, isothermally or quasi-isothermally operated steam pretreatment reactor. By means of the external steam pretreatment according to the invention, higher lifetimes of the catalyst used are obtained as compared to a steam pretreatment in the OTO reactor. The availability of the OTO reactor for the olefin production is increased.