Oxygenate separation following oxidative dehydrogenation of a lower alkane

A system comprising:

• an oxidative dehydrogenation (ODH) reactor to convert a lower alkane to an alkene in presence of oxygen and discharge an ODH outlet stream comprising the alkene, an oxygenate, and a carbon-based oxide;
• a heat exchanger to cool the ODH outlet stream to condense oxygenate in the ODH outlet stream;
• a flash tower to receive the ODH outlet stream as cooled from the heat exchanger and discharge an alkene outlet stream comprising the alkene and the carbon-based oxide and discharge a first oxygenate outlet stream comprising oxygenate as condensed and water;
• a quench tower to contact the alkene outlet stream with a quenching agent comprising water and carbonate to remove remaining oxygenate from the alkene and discharge a first quench outlet stream comprising the alkene and carbon-based oxide and a second quench outlet stream comprising acetate, water, and remaining oxygenate;
• an extraction tower to receive the first oxygenate outlet stream and the second quench outlet stream to separate oxygenate from acetate and water and discharge a first extraction outlet stream comprising oxygenate and a second extraction outlet stream comprising acetate and water;
• and
• a recycle line to recycle to the extraction tower a portion of the extraction outlet stream as discharged.

A system comprising:

• an oxidative dehydrogenation (ODH) reactor to receive oxygen and an alkane, convert the lower alkane to an alkene, and discharge an ODH outlet stream comprising the alkene, an oxygenate, and a carbon-based oxide;
• a heat exchanger to cool the ODH outlet stream to condense oxygenate in the ODH outlet stream;
• a flash tower to receive the ODH outlet stream as cooled from the heat exchanger and discharge an alkene outlet stream comprising the alkene and the carbon-based oxide and discharge a first oxygenate outlet stream comprising oxygenate as condensed and water;
• a quench tower to contact the alkene outlet stream with a quenching agent comprising water and carbonate to separate remaining oxygenate from the alkene and convert remaining oxygenate by contact with carbonate into acetate and discharge a first quench outlet stream comprising the alkene and carbon-based oxide and a second quench outlet stream comprising acetate, water, and remaining oxygenate;
• an extraction tower to receive the first oxygenate outlet stream and the second quench outlet stream to separate oxygenate from acetate and water and discharge a first separation outlet stream as a second oxygenate outlet stream comprising oxygenate and a second separation outlet stream as an extraction outlet stream comprising acetate and water;
• and
• a recycle line to recycle directly to the extraction tower a portion of the extraction outlet stream as discharged.