Patent ID: 7115789

Claim:
A process for hydrogenating byproducts selected from the group consisting of alkynes, dienes and mixtures thereof in an olefin product stream from an oxygenate-to-olefins reactor, the process comprising the steps of: (a) contacting an oxygenate with a molecular sieve catalyst in the oxygenate-to-olefins reactor to provide the olefin product stream; (b) isolating from the olefin product stream a first olefin stream containing 25 mol. % or more ethylene or 25 mol. % or more propylene, based upon the composition of the first olefin stream, and 500 mppm or less of the alkyne or diene byproduct; (c) hydrogenating the first olefin stream to produce a second olefin stream; and (d) hydrogenating the second olefin stream in the presence of from 100 mppm to 1000 mppm hydrogen, based upon the weight of the second olefin stream, to produce a third olefin stream containing 20 mppm or less hydrogen, based upon the composition of the third olefin stream.