NOVELTY - Conversion of methanol to olefins, comprises contacting methanol and at least one of air and nitrogen in methanol-to-olefins reactor system (10); recovering an effluent (106) from the methanol-to-olefins reactor system comprising e.g. methanol and nitrogen oxides; and separating the effluent via one or more extractive distillation and/or distillation stages to recover a first fraction comprising ethylene and a second fraction comprising methane.    USE - The process is useful for the conversion of methanol to olefins e.g. ethylene, which is useful for producing various derivatives e.g. polyethylene for many commercial as well as consumer products and applications.    ADVANTAGE - The method is an improved method for treating methanol-to-olefin process effluent to separate and recover ethylene and other valuable products that reduces the capital and operating costs and improves the operation safety and stability. The process reduces the capital equipment costs; utilizes less expensive metallurgy; eliminates the number of equipment items associated with the chill train; and is not conducted at cryogenic temperatures.    DETAILED DESCRIPTION - Conversion of methanol to olefins, comprises: contacting methanol and at least one of air and nitrogen in a methanol-to-olefins reactor system (10); recovering an effluent (106) from the methanol-to-olefins reactor system comprising methanol, dimethyl ether, methane, ethylene, and nitrogen oxides including nitric oxide and nitrogen dioxide; and separating the effluent via one or more extractive distillation and/or distillation stages to recover a first fraction comprising ethylene and a second fraction comprising methane; where the separating step comprises operating the one or more extractive distillation and/or distillation stages at temperatures and pressures sufficient to prevent any substantial conversion of nitrogen oxides to nitrogen oxide (N2O3). INDEPENDENT CLAIMS are included for:    (1) the conversion of methanol to olefins, comprising contacting methanol and at least one of air and nitrogen in a methanol-to-olefins reactor system; recovering an effluent from the methanol-to-olefins reactor system comprising methane, ethylene, and nitrogen oxides including nitric oxide and nitrogen dioxide, feeding at least a portion of the methanol-to-olefins reactor system effluent to an extractive distillation column; countercurrently contacting the methanol-to-olefins reactor system effluent with at least one 2-4C hydrocarbon in the extractive distillation column to produce an overhead fraction (108) comprising methane and a bottoms fraction comprising the 2-4C hydrocarbon and ethylene; operating the extractive distillation column at conditions sufficient to absorb ethylene in the 2-4C hydrocarbon and to prevent any substantial conversion of the nitrogen oxides to N2O3; and    (2) conversion of methanol to olefins, comprising: feeding at least a portion of a methanol-to-olefins reactor effluent comprising methane and ethylene to an extractive distillation column; countercurrently contacting the reactor effluent with at least one 2-4C hydrocarbon in the extractive distillation column to produce an overheads fraction comprising methane and a bottoms fraction comprising the at least one 2-4C hydrocarbon and ethylene.    DESCRIPTION OF DRAWING(S) - The figure shows a simplified flow diagram for a methanol-to-olefins process.    Methanol-to-olefins reactor system (10)    Extraction distillation system (12)    Effluent (106)    Over-heads fraction. (108, 110)