Integrated carbon capture and utilization to convert CO2 to formic acid and formaldehyde

Abstract

Carbon utilisation is gaining attention on a scientific and public level, as part of a strategy to close the carbon cycle. Existing CO2 utilisation strategies, based on the use of pure CO2, lead to relatively high cost for e-fuels and commodity chemicals. This paper proposes an integration of CO2 capture with CO2 utilisation, directly in the CO2 capture solvent, to improve the cost performance. In this concept, ammonium bicarbonate is produced by CO2 capture and subsequently hydrogenated to ammonium formate. With the use of a thermal split, the ammonium formate can be split into a formic acid product solution and ammonia. Techno-economics show the potential of this route supported by proof-of-concept experiments for the innovative steps in the process. Assessment of a 100 ktonne/y CO2 capture and utilization leads to a formic acid production price of 365-456 €/t, using a varying hydrogen price of 2-4 €/kg, which is in the price range of industrial formic acid.