Method for stabilizing catalyst activity during MTO unit operation
AssigneeExxonMobil Chemical Patents Inc.
InventorsShun Fung, Richard Hall, Hafedh Kochkar, Karl Strohmaier, Nicolas Coute, Kenneth Clem
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Abstract
A method for maintaining the activity of silicoaluminophosphate (SAPO) molecular sieve catalyst particles during oxygenate to olefin conversion reactions. After regeneration of SAPO catalyst particles, the regenerated particles are mixed with particles having coke on their surface in a manner that maintains their catalytic activity at a predetermined level.
Claims15
-37. (canceled)
A process for forming polyolefins, comprising:
- a) converting an oxygenate feedstock into olefins by exposing the oxygenate feedstock to silicoaluminophosphate molecular sieve catalyst particles;
- b) regenerating silicoaluminophosphate molecular sieve catalyst particles to contain less than about 1% coke by weight relative to a weight of molecular sieve material within the regenerated catalyst particles;
- c) mixing the regenerated silicoaluminophosphate molecular sieve catalyst particles with coked catalyst particles containing at least 2% coke by weight relative to a weight of molecular sieve material within the coked catalyst particles to maintain the catalytic activity of the mixed catalyst particles at a predetermined level;
- and
- d) forming polyolefins from the converted olefins.
(canceled)
50-65. (canceled)
The process of claim 55, wherein the regenerated catalyst particles are mixed with the oxygen-containing gas in a catalyst cooler prior to being mixed with the coked catalyst particles.
Dependencies are inferred from the claim text.