CONVERSION OF METHANOL TO LOWER OLEFINS - KINETIC MODELING, REACTOR SIMULATION, AND SELECTION

Reactor types for commercial-scale methanol-to-olefins (MTO) processes in the ethene mode, using a small-pore molecular-sieve catalyst, have been evaluated both qualitatively and quantitatively. A kinetic model has been developed via an iterative process of model formulation, par ameter estimation, and model validation. The final model consists of 1 2 reactions involving 6 component lumps plus coke. Important factors a re the occurrence of consecutive reactions and the effect of coke on b oth the activity and selectivity. This kinetic model has been implemen ted in mathematical models of various reactors for the estimation of p roduct selectivities and main reactor dimensions. These formed the bas is for a comparison of different reactor types for a commercial-scale process. A circulating fast fluidized-bed reactor and a turbulent flui dized-bed reactor emerged as the most promising reactor systems for MT O in the ethene mode; ethene/propene ratios of 1-1.5 can be achieved w ith realistic reactor dimensions.