Industrial carbon monoxide production by thermochemical CO2 splitting – A techno-economic assessment

Abstract

This research presents the splitting of carbon dioxide (CO2) by Ba2Ca0.66Nb0.34FeO6 (BCNF1) at the 100 g scale and the techno-economic assessment of a carbon-neutral carbon monoxide (CO) production facility based upon this perovskite. BCNF1 was found to convert 10.1 % of CO2 to CO with 100 % selectivity at 800 °C, which was sustained for five thermochemical cycles showing little sign of degradation. This oxidation reaction was found to proceed via a zero order reaction mechanism at 800 °C, with an activation energy of 46.6 kJ/mol. This activation energy for CO2 splitting is lower than all bar one of the perovskites investigated in the literature, explaining the lower oxidation temperature required and higher CO yields of this material. Economic evaluation of an industrial scale-up system based on this data suggested profitability despite high sensitivity to electricity prices, as expected. A 150 m3/hr plant would produce CO at $0.15 per kg at the average industrial US electricity price of $0.068/kWh. This is significantly cheaper than reported costs of electrochemically produced CO in the literature. As electricity prices fall due to abundant renewables, larger production volumes become optimal, with $1.3 million a year profits for a 500 m3/hr plant at $0.05/kWh.