Co@Hcn Derived from Hzif-67 as a Highly Efficient Catalyst for Catalytic Hydrogenation of O-Cresol to O-Methyl Cyclohexanol

Abstract

The selective hydrogenation of o-cresol to o-methyl cyclohexanol is an attractive approach. The development of efficient non-precious metal catalysts for the selective o-cresol hydrogenation remain a great challenge. Herein, cobalt nanoparticles embedded in nitrogen-doped carbon with hollow structure (Co@HCN) were fabricated by direct pyrolysis of hollow zeolitic imidazolate framework-67 (HZIF-67), and were applied in the selective hydrogenation of o-cresol to o-methyl cyclohexanol for the first time. The pyrolysis temperature and Co(NO3)2•6H2O concentration jointly regulate the morphology and physicochemical properties of the Co@HCN catalysts, and significantly affect their catalytic properties. Co@HCN-500-0.1 exhibits superior catalytic activity, which is 3.3 times higher than Co@HCN-700-0.1 and 1.3 times higher than Co@HCN-500-0.4. Large ratio of meso-/macro-porous specific surface area and pore volume, small Co size with uniform dispersion, and abundant surface Co and CoNx contents together contribute to the superior catalytic activity of Co@HCN-500-0.1. More importantly, Co@HCN-500-0.1 displays superior catalytic recyclability and universal applicability.

Keywords: o-Cresol, o-Methyl cyclohexanol, Zeolitic imidazolate frameworks, N-doped carbon, Hollow structure