A method for controlling the carbon dioxide output from an oxidative dehydrogenation process comprising the steps of: i) introducing a gas mixture comprising a lower alkane and oxygen, and optionally one or more of steam and inert diluent, into at least one ODH reactor containing the same or different ODH catalysts, provided at least one of the ODH catalysts is capable of utilizing carbon dioxide as an oxidizing agent, under conditions to produce a product stream from each at least one ODH reactor comprising corresponding alkene, and possibly one or more of unreacted lower alkane, unreacted oxygen, carbon dioxide, carbon monoxide, inert diluent, and acetic acid; ii) measuring carbon dioxide levels in one or more said product streams; and either: a. introducing steam, or increasing amount of steam introduced, into the at least one ODH reactor in an amount sufficient to decrease the carbon dioxide output levels when the measured carbon dioxide level is above a predetermined target carbon dioxide level; b. decreasing the flow rate of steam introduced into the at least one ODH reactor to increase the carbon dioxide output levels when steam was introduced in step i) and the measured carbon dioxide level is below the predetermined target carbon dioxide level; c. increasing the volumetric ratio of oxygen to lower alkane in the gas mixture introduced into the at least one ODH reactors to a degree sufficient to decrease the carbon dioxide levels when the measured carbon dioxide level is above a predetermined target carbon dioxide level; or d. decreasing the volumetric ratio of oxygen to lower alkane in the gas mixture introduced into the at least one ODH reactor to a degree sufficient to increase the carbon dioxide level when the measured carbon dioxide level is below a predetermined target carbon dioxide level. i) introducing a gas mixture comprising a lower alkane and oxygen, and optionally one or more of steam and inert diluent, into at least one ODH reactor containing the same or different ODH catalysts, provided at least one of the ODH catalysts is capable of utilizing carbon dioxide as an oxidizing agent, under conditions to produce a product stream from each at least one ODH reactor comprising corresponding alkene, and possibly one or more of unreacted lower alkane, unreacted oxygen, carbon dioxide, carbon monoxide, inert diluent, and acetic acid; ii) measuring carbon dioxide levels in one or more said product streams; a. introducing steam, or increasing amount of steam introduced, into the at least one ODH reactor in an amount sufficient to decrease the carbon dioxide output levels when the measured carbon dioxide level is above a predetermined target carbon dioxide level; b. decreasing the flow rate of steam introduced into the at least one ODH reactor to increase the carbon dioxide output levels when steam was introduced in step i) and the measured carbon dioxide level is below the predetermined target carbon dioxide level; c. increasing the volumetric ratio of oxygen to lower alkane in the gas mixture introduced into the at least one ODH reactors to a degree sufficient to decrease the carbon dioxide levels when the measured carbon dioxide level is above a predetermined target carbon dioxide level; or d. decreasing the volumetric ratio of oxygen to lower alkane in the gas mixture introduced into the at least one ODH reactor to a degree sufficient to increase the carbon dioxide level when the measured carbon dioxide level is below a predetermined target carbon dioxide level.