Processes for lifting spent catalyst into a regenerator in an oxygenate to olefins reaction system

A process for forming light olefins, wherein the process comprises the steps of:

• (a) contacting an oxygenate with a molecular sieve catalyst in a reactor under conditions effective to form an effluent stream comprising light olefins and to deposit coke on the molecular sieve catalyst to form a coked catalyst comprising more than 1 weight percent carbonaceous deposits;
• (b) transporting the coked catalyst from the reactor to a catalyst regenerator through a conduit in a fluidized manner with a fluidizing medium comprising air and steam;
• (c) regenerating the coked catalyst in the catalyst regenerator to form regenerated catalyst;
• and
• (d) directing the regenerated catalyst back to the reactor.

A process for lifting molecular sieve catalyst through a lift line, wherein the process comprises the steps of:

• (a) contacting the molecular sieve catalyst with a lifting medium comprising air under conditions effective to lift the molecular sieve catalyst through the lift line, wherein the molecular sieve catalyst comprises more than 1.0 weight percent carbonaceous deposits, based on the total weight of the carbonaceous deposits and the molecular sieve catalyst;
• (b) determining the temperature of the lift line or the molecular sieve catalyst contained therein;
• and
• (c) reducing the amount of air in the lifting medium responsive to a determination that the temperature has exceeded a predetermined maximum temperature.