ABSTRACT This study reports the synthesis of nitrogen‐doped hierarchical porous carbons (NHPC) derived from nitrogen‐containing biomass precursors (glucosamine hydrochloride/chitosan) through urea/sodium bicarbonate co‐activation. Critically, biomass‐derived NHPC carriers exhibit substantially enhanced surface areas (2,535 m 2 g −1 ) and reduced microporous volumes (0.13 cm 3 g −1 ) compared to conventional carbon supports, attributed to heteroatom self‐doping effects and gas‐evolving activation mechanisms. Systematic optimization of calcination parameters (500°C–900°C; 3°C–10°C/min; 0.5–3 h) and copper loading (5–10 wt%) yielded the optimal 5Cu/10NHPC GAH ‐1‐800 catalyst. The unique pore architecture features: (i) Expanded mesopore channels facilitating reactant diffusion, (ii) Diminished microporous volume minimizing mass transfer barriers, and (iii) Nitrogen‐anchoring sites stabilizing copper nanoparticles. In DMC synthesis, this catalyst delivered 17.26% methanol conversion and DMC space‐time yield of 24.54 g·(g·h) −1 for copper‐based systems. The biomass‐NHPC supports structural advantages conferred exceptional stability—retaining 60% initial activity after 10 cycles. The reduced microporosity and maximized meso/macropore network directly suppressed coke deposition while enabling efficient copper dispersion, as verified by SEM/TEM pore distribution analyses. This work establishes nitrogen‐rich biomass as superior precursor for engineering mass‐transfer‐optimized catalyst supports, resolving persistent challenges in non‐corrosive DMC production.
Zhao et al. (Fri,) studied this question.