The effect of nitrogen doping on hydrogenation capability and stability of Cu-based catalyst in ester hydrogenation to methyl glycolate

Methyl glycolate (MG) was a significant chemical raw material of biodegradable and bioabsorbable polyglycolic acid (PGA). In this work, the N-doped layered carbon supported Cu catalysts were constructed for dimethyl oxalate (DMO) hydrogenation to MG. Nitrogen doping had significant effects on the particle size, valence state and electronic environment of Cu species. The electronic interaction between Cu species and N-doped carbon support improved the Cu0/(Cu0 + Cu+) ratio and electron density surrounding Cu species in N-doped catalysts. The synergistic effect of high Cu0/(Cu0 + Cu+) ratio and electron density made Cu species in Cu/C-E catalyst showed up to 74.84% MG yield. More importantly, the intimate interaction between Cu species and N-doped carbon support improved the thermal and valence stability of Cu catalyst, resulting in the Cu/C-E catalyst with a much higher stability of over 600 h than the currently reported Cu catalyst.