CO2 electrochemical reduction: a state-of-the-art review with economic and environmental analyses

Abstract

The electrochemical reduction of carbon dioxide is an emerging strategy to reduce emissions, allowing the storage of renewable energy and the electrification of the chemical industry according to the principle of carbon dioxide utilization. Valuable fuels and chemical commodities can be obtained by ensuring a closed carbon loop and the main important products are carbon monoxide, formic acid, methanol, methane, ethylene, ethanol, and propanol. Inside this context, here, we explore the state-of-the-art of carbon dioxide electrolysis technologies, showing that efforts have been put into the development of reactor cell architectures and catalysts able to provide high selectivity and efficiency. New insights are currently about the study of reaction mechanisms, optimization of cell design, and development of more performing electro-catalysts. Moreover, an overview of economic and environmental studies based on carbon dioxide electrochemical reduction is conducted in this work and a preliminary screening based on the levelized production cost and climate change impact of several products obtained through carbon dioxide electrochemical reduction is proposed for a large-scale plant. Today, carbon monoxide and formic acid are the primary carbon dioxide reduction product targets from an economic point of view. In the future, production costs are expected to decrease, and other low-carbon products could be competitive with market prices. Renewable energy sources and carbon dioxide with a low carbon footprint contribute to an environmentally friendly electrochemical production process.