Direct conversion of carbon dioxide and steam into hydrocarbons and oxygenates using solid acid electrolysis cells

Naoya Fujiwara; Shohei Tada; Ryuji Kikuchi

doi:10.1016/j.isci.2022.105381

Direct conversion of carbon dioxide and steam into hydrocarbons and oxygenates using solid acid electrolysis cells

iScience. 2022 Nov 9;25(11):105381. doi: 10.1016/j.isci.2022.105381. eCollection 2022 Nov 18.

Authors

Naoya Fujiwara¹, Shohei Tada², Ryuji Kikuchi²

Affiliations

¹ Department of Chemical System Engineering, The University of Tokyo, Bunkyo-ku, Tokyo 113-8656, Japan.
² Division of Applied Chemistry, Faculty of Engineering, Hokkaido University, Kita-ku, Sapporo 060-8628, Japan.

Abstract

Electrolysis at intermediate temperatures (100-600°C) is promising because high reaction rates and high product selectivity can be achieved simultaneously during CO₂ reduction. However, intermediate temperature electrolysis has rarely been reported owing to electrolyte limitations. Here, solid acid electrolysis cells (SAECs) were adopted for electrochemically reducing CO₂. Carbon monoxide, methane, methanol, ethane, ethylene, ethanol, acetaldehyde and propylene were produced from CO₂ and steam, using Cu-containing composite cathodes at 220°C and atmospheric pressure. The results demonstrate the potential of SAECs for producing valuable chemical feedstocks. At the SAEC cathode, CO₂ was electrochemically reduced by protons and electrons. The product selectivity and reaction rate were considerably different from those of thermochemical reactions with gaseous hydrogen. Based on the differences, plausible reaction pathways were proposed.

Keywords: Chemical Engineering; Chemistry; Electrochemistry; Process Engineering.