Liquid Humins: A Sustainable Carbonaceous Feedstock for Pd/C Catalysts Design with a Reduced "Dead" Metal Effect

Humins, a by-product of biomass-to-furanics processing, are sustainable and underutilized carbonaceous feedstock. This study introduces liquid humins as precursors for synthesizing innovative carbon materials tailored for Pd/C catalysts. These materials mitigate the "dead" metal issue, where inaccessible Pd particles hinder catalytic efficiency. By exploring methods to convert liquid humins into carbon materials with optimized porous structures and nitrogen doping, Pd/C catalysts with significantly enhanced performance are developed. A novel carbon support derived from a composite of thermally cured humins and melamine exhibits low microporosity and high nitrogen content, thereby minimizing Pd encapsulation. Catalytic applications of these Pd/C materials in Suzuki-Miyaura, Mizoroki-Heck, and nitroarene hydrogenation reactions demonstrate superior activity, surpassing many existing biomass-derived Pd/C catalysts. The work highlights humins as a renewable resource for high-performance catalyst development, addressing critical sustainability and efficiency challenges in catalysis. This approach opens new avenues in green chemistry and valorization of industrial by-products, paving the way for cost-effective and scalable applications in organic synthesis.