Vitamin C‐Assisted Cu–Co Bimetallic Catalysts for Selective Hydrogenation of 5‐Hydroxymethylfurfural to 2,5‐Dimethylfuran

ABSTRACT Biomass‐derived 2,5‐dimethylfuran (DMF) is widely used in the fuel industry, yet the efficient hydrodeoxygenation (HDO) of 5‐hydroxymethylfurfural (HMF) to DMF using nonnoble metal catalysts remains challenging. Herein, a CuCo bimetallic catalyst was synthesized by a simple, eco‐friendly solid‐state grinding method with vitamin C (VC) as an additive. Under optimal conditions, the DMF yield exceeded 80%, superior to monometallic catalysts. The CuCo catalyst also displayed good stability and reusability. Characterization results indicated that appropriate VC addition enriched the catalyst's pore structure, increased its specific surface area, and improved reaction efficiency. Additionally, VC promoted the dispersion of low‐valent Cu and Co species, enhancing catalytic reduction activity. Mechanistic analysis showed that HMF is preferentially hydrogenated to 2,5‐bishydroxymethylfuran (BHMF) at Cu 0 /Co 0 hydrogenation sites, with a small amount converted to 5‐methylfurfural (5‐MF) under acidic conditions. 5‐Methylfurfuryl alcohol (MFA) serves as a key intermediate for both pathways, ultimately yielding DMF via hydrodeoxygenation at acidic sites.