Nitrogen-Doped Co Catalyst Derived from Carbothermal Reduction of Cobalt Phyllosilicate and its Application in Levulinic Acid Hydrogenation to γ-Valerolactone

An active and stable Co catalyst decorated by N species was developed and applied in the hydrogenation of levulinic acid (LA) to gamma-valerolactone (GVL). The catalyst was first synthesized by grafting glucose (G) and melamine (M) on cobalt phyllosilicate (CoPS) hydrothermally, and then by pyrolyzing GM/CoPS at a designated temperature for the carbothermal reduction (denoting as GM@CoPS-X; X = temperature). Among tested catalysts, GM@CoPS-700 showed the most promising GVL productivity (1684 mmol GVL/g(surface Co) /h), stability, and recyclability (an ca. 8% loss of initial activity) in five consecutive trials. Doped N species were found to improve the concentration of Co delta+ (0 < delta < 2) with a strong Lewis acidity. The synergy of Co delta+ and Co-0 was the key in enhancing the activity of Co-based catalysts derived from CoPS. [GRAPHICS] .

Automated summary

An active and stable Co catalyst decorated by N species was developed and applied in the hydrogenation of levulinic acid to gamma-valerolactone. The doped N species improved the concentration of Co delta+ with strong Lewis acidity, enhancing the activity of Co-based catalysts derived from CoPS.