Catalytic Hydrogenation of Carbon Dioxide to Methane, Methanol, and Ethanol

Abstract

Catalytic hydrogenation of carbon dioxide represents a promising route to mitigate greenhouse gas emissions while converting CO into valuable chemicals and fuels. This work reviews recent developments in the catalytic conversion of CO to three representative products: methane, methanol, and ethanol. Methanation commonly employs nickel-based catalysts that combine low cost with high activity, yet challenges remain in selectivity and long-term stability; improvements in catalyst architecture and heat management have advanced reactor performance. Methanol production is dominated by copper-based systems whose activity and selectivity depend sensitively on electronic structure and support effects; the introduction of oxide, carbide, and bimetallic materials has materially enhanced selectivity and durability. Ethanol synthesis from CO is attractive because of ethanols higher energy density and broader applications, but it requires overcoming CC coupling barriers; bimetallic and single-atom catalysts have shown promise, although the development of efficient and stable catalytic systems is still an open challenge. The review highlights mechanistic differences among the three product pathways and emphasizes catalyst design, mechanistic understanding, and reactor engineering as key directions toward practical implementation.