Systems and methods are provided for using an oxygen-containing gas as at least part of the stripping gas for the stripping zone or section in a fluidized coker. By using an oxygen-containing gas as the stripping gas, heat can be added to the stripping zone selectively based on combustion of coke and/or hydrocarbons with the oxygen in the stripping gas. This can allow the temperature of the stripping zone to be increased relative to the temperature of the coking zone of a fluidized coking system. The flow of oxygen can be controlled to achieve a desirable temperature in the stripper while the reactor temperature is independently set by preheating of the feed and/or hot coke circulation to the reaction zone.