Economic Low‐Carbon Chemical Production via Paired Electrolysis of Carbon Monoxide (CO) and 5‐hydroxymethylfurfural (HMF)

ABSTRACT Paired electrolysis of CO 2 and biomass‐derived alcohols, such as 5‑hydroxymethylfurfural (HMF) and glycerol, offers a sustainable approach for co‐producing valuable chemicals, but suffers from poor cathode‐anode compatibility and limited economic feasibility. Herein, we show that replacing CO 2 with carbon monoxide (CO) and adopting a catholyte‐layer electrolyzer design jointly enhance the operational stability of alcohol‐paired electrolysis by preventing HCO 3 − formation and suppressing inter‑electrode mass exchange. Within this platform, HMF oxidation is identified as the optimal anodic partner compared with glycerol oxidation, because it exhibits negligible product crossover and the oxidation kinetics of its intermediates consistently outpace those of the oxygen evolution reaction. Consequently, the paired electrolysis of CO and HMF in a membrane‐electrode assembly electrolyzer incorporating a catholyte‐layer enabled efficient and stable co‑production of ethylene and 2,5‑furandicarboxylic acid (FDCA), both key plastic monomers derived from CO 2 and biomass, respectively. Techno‐economic and environmental assessment indicate that the CO‐HMF pairing outperforms all tested combination of CO 2 or CO‐HMF or glycerol and approaches the production cost and carbon emission to petroleum‐derived terephthalic acid. These results demonstrate CO electrolysis coupled with HMF oxidation as a cost‐effective and climate‐conscious strategy for sustainable chemical production.