Methanol to olefins—prediction of the performance of a circulating fluidized-bed reactor on the basis of kinetic experiments in a fixed-bed reactor

Abstract

The conversion of methanol to olefins (MTO) over a zeolite catalyst is used as an example for the investigation of a circulating fluidized bed (CFB) reactor/regenerator system. A lumped-species reaction scheme has been developed which accounts for the most relevant components. Kinetic experiments were carried out in a standard fixed-bed Berty reactor over the 400°C to 500°C range at atmospheric pressure. The MTO process was performed in a circulating fluidized bed (riser dimensions: internal diameter 0.03 m, height 11 m) that is coupled with a regenerator for continuously burning off the coke deposits. Conversion of more than 98% and a very high olefin selectivity have been achieved. Based on the estimated kinetic parameters and on a CFB reactor model, methanol conversion and product distribution is predicted and compared with experimental data. The agreement is satisfactory for the whole temperature range examined.