Patent ID: 7781362
Filing Date: 2010-08-24
Classification: B01J

Abstract:
1. A method for regenerating molecular sieve catalyst in an oxygenate-to-olefin reaction system, comprising: receiving a recycled catalyst into a regenerator; receiving a gas flow in the regenerator for replenishing a regeneration medium, the gas flow received by drawing in air from the vicinity of the regenerator through a conduit fluidly connected to an air compressor, the compressor compressing the air to approximately match the pressure within the regenerator, followed by allowing the compressed air into the regenerator; detecting a metal salt content above a threshold value in the gas flow; wherein detecting a metal salt content comprises forming a solution from metal salt contained in a sampling stream; and detecting a conductivity of the metal salt solution; wherein the sampling stream is collected from the received gas flow and wherein the metal salt content is detected prior to compressing the received gas flow; activating a secondary gas flow; wherein activating a secondary gas flow comprises activating a gas flow from a gas storage vessel, wherein the secondary gas flow is air or a mixture of nitrogen and oxygen with levels of metal salt below a second threshold; and compressing the air to the pressure of the regenerator and adding the secondary gas flow to a regeneration medium for regenerating molecular sieve catalyst in an oxygenate-to-olefin reaction system; and wherein the regeneration takes place at a temperature of greater than 590° C. and the residence time of the catalyst is at least 10 min.