Fremgangsmåte for öking av selektiviteten til en reaksjon for å omdanne oksygenater til olefiner

摘要

Disclosed is a method of making an olefin product from an oxygenate feedstock comprising, contacting the feedstock in a reaction zone containing 15 volume percent or less of a catalyst, preferably a catalyst comprising a silicoaluminophosphate molecular sieve. In order to obtain the desired product content, i.e., an olefin product having a low level of by-products, conversion of the feedstock in the 15 volume percent or less reaction zone should be maintained between 80 wt % and 99 wt % at the conditions effective to convert 100 wt % of the feedstock when the reaction zone contains at least 33 volume percent of the catalyst material.