The average cycle propylene selectivity of an oxygenate to propylene (OTP) process using one or more fixed beds of a dual-function oxygenate conversion catalyst is substantially enhanced by the use of moving bed reactor technology in the hydrocarbon synthesis portion of the OTP flow scheme in lieu of fixed bed technology coupled with the selection of a catalyst on-stream cycle time of 200 hours or less. Those provisions hold the build-up of coke deposits on the catalyst to a level which does not substantially degrade dual-function catalyst activity, oxygenate conversion and propylene selectivity, thereby enabling maintenance of propylene average cycle yield at essentially start-of-cycle levels. The propylene average cycle yield improvement enabled by the present invention over that achieved by the fixed bed system of the prior art using the same or a similar catalyst system is of the order of about 1.5 to 5.5 wt-% or more.

 
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