Method for increasing light olefin yield by conversion of a heavy hydrocarbon fraction of a product to light olefins

摘要

A method for increasing light olefin yield during conversion of oxygenates to olefins including contacting an oxygenate feed in a primary reactor with a non-zeolitic molecular sieve catalyst under first conditions effective to produce a first product comprising light olefins; separating the first product into light olefins and a heavy hydrocarbon fraction; feeding the heavy hydrocarbon fraction to a separate auxiliary reactor; and, subjecting the heavy hydrocarbon fraction to second conditions effective to convert at least a portion of the heavy hydrocarbons to light olefins.