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.