Direct electrocatalytic conversion of crude syngas to ethylene via a multi-process coupled device

Abstract

Direct electrocatalytic conversion of crude syngas is an economical and ideal strategy for producing value-added ethylene without CO₂ emission, which can directly use H₂O instead of H₂ as the clean hydrogen source at atmospheric pressure and room temperature. However, H₂S impurities in the syngas inevitably poison the catalysts and the sluggish anodic oxygen evolution reaction induces substantial electricity losses, which largely hinder the overall efficiency of the electrolysis process. Herein, we developed an energy-saving carbon reduction multi-process coupled electrolysis device for the conversion of H₂S-containing syngas, which not only realized a high faradaic efficiency (FE) of ethylene with the removal of H₂S impurities but also increased the ratio of H₂/CO in the residual syngas and reduced the total energy consumption of electrolysis. This “Four in One” device can typically remove 10% H₂S from syngas and obtain an ethylene FE of up to 49.7%, which saves 46.5% energy as compared to the uncoupled device.