Method for preparing ethylene propylene

A process for producing ethylene-propylene in a reaction system comprising a first reactor and a second reactor, the first reactor comprising a fast bed reactor, a fast bed settler, and a first riser tube, the second reactor comprising a second riser tube and a riser settler, comprising:

• a) in the first reactor, feeding a methanol feedstock and a catalyst into the fast bed reactor, obtaining a reaction product I and a first particulate catalyst produced by partial inactivation of the catalyst, which exits from the fast bed reactor and enters the fast bed settler;
• b) in the second reactor, feeding a first feedstock and a regenerated catalyst into the second riser tube, producing a first mixture comprising a reaction product II and a second particulate catalyst, wherein the first mixture exits the second riser tube and enters the riser settler to separate a reaction product II from the second particulate catalyst, separating the second particulate catalyst into a first part of the second particulate catalyst and a second part of the second particulate catalyst;
• c) in the first reactor, feeding the second part of the second particulate catalyst into the first riser tube, producing a second mixture comprising a third particulate catalyst, wherein the second mixture exits the first riser tube and enters the fast bed settler;
• and
• d) obtaining a mixed catalyst comprising the first particulate catalyst the third particulate catalyst in the fast bed settler, and feeding a first part of the mixed catalyst and the first part of the second particulate catalyst into a regenerator for regeneration to obtain the regenerated catalyst,
• wherein the first feedstock is selected from an oxygenate feedstock, a light hydrocarbon feedstock, and a mixture thereof, the oxygenate feedstock comprises water and oxygenates, the oxygenates are present in an amount of from 5 to 60 wt % of the oxygenate feedstock, and the light hydrocarbon feedstock comprises a C4-C6 non-aromatic hydrocarbon mixture;
• and
• wherein the fast bed reactor, the fast bed settler and the first riser tube are coaxially arranged, and the first riser tube has a riser outlet, and the fast bed reactor has a fast bed outlet, and both the riser outlet and the fast bed outlet are disposed in the fast bed settler.