Ambient-pressure hydrogenation of CO2 into long-chain olefins

Abstract

The conversion of CO₂ by renewable power-generated hydrogen is a promising approach to a sustainable production of long-chain olefins (C₄₊⁼) which are currently produced from petroleum resources. The decentralized small-scale electrolysis for hydrogen generation requires the operation of CO₂ hydrogenation in ambient-pressure units to match the manufacturing scales and flexible on-demand production. Herein, we report a Cu-Fe catalyst which is operated under ambient pressure with comparable C₄₊⁼ selectivity (66.9%) to that of the state-of-the-art catalysts (66.8%) optimized under high pressure (35 bar). The catalyst is composed of copper, iron oxides, and iron carbides. Iron oxides enable reverse-water-gas-shift to produce CO. The synergy of carbide path over iron carbides and CO insertion path over interfacial sites between copper and iron carbides leads to efficient C-C coupling into C₄₊⁼. This work contributes to the development of small-scale low-pressure devices for CO₂ hydrogenation compatible with sustainable hydrogen production.

The conversion of CO2 by renewable power-generated hydrogen is a promising approach to a sustainable production of long-chain olefins. Here the authors report a Cu-Fe catalyst which achieves the hydrogenation of CO2 into long-chain olefins under ambient pressure via the synergy of carbide mechanism and CO insertion mechanism.