Isobutanol production process

The process of wherein the second reaction conditions comprise at least one of:

• a temperature in a range of about 200° C. to about 500° C.;
• a pressure in a range of about 0.1 to about 30 MPa;
• 0.1-50 mol % propanol and balance syngas with a ratio of H2 to CO in a range of about 5:1 to about 1:5;
• or a gas hourly space velocity in a range of about 100 to about 500,000 liters of gas per kg of catalyst per hr (L/kg-h).

A process for the production of isobutanol comprising:

• reacting methanol with ethanol in a first reaction zone in the presence of a first catalyst under first reaction conditions to produce a first reaction mixture comprising propanol;
• separating the first reaction mixture in a first separation zone into a propanol stream comprising the propanol, an isobutanol stream comprising isobutanol, an n-butanol stream comprising n-butanol, and either a methanol stream comprising methanol and an ethanol stream comprising ethanol, or a combined methanol-ethanol stream comprising methanol and ethanol;
• reacting the propanol with synthesis gas in a second reaction zone in the presence of a second catalyst under second reaction conditions to produce a second reaction mixture comprising isobutanol;
• separating the second reaction mixture in a gas-liquid separation zone into a gas stream comprising H2, CO, CO2, CH4, and light hydrocarbons and a liquid stream comprising methanol, ethanol, propanol, isobutanol and n-butanol;
• and
• at least one of:
• introducing at least one of the methanol stream, the ethanol stream, or the combined methanol-ethanol stream to the first reaction zone;
• and
• introducing the propanol stream to the second reaction zone.