Hyper-crosslinked polymer derived porous Co@CN catalyst for selective hydrogenation of quinoline

Abstract

A benzotrizole-based hyper-crosslinked polymer (HCP) was employed to load cobalt and prepare a novel metal-containing nitrogen-doped carbon catalyst for the selective hydrogenation of quinoline. The high porosity, large surface area and nitrogen-containing monomer of HCP made a positive contribution to metal loading. Owing to the excellent thermostability of HCP, the original porous texture of HCP was partially reserved during pyrolysis, which resulted in highly dispersive Co species in the N-doped carbon material. The remaining mesopores in Co@CN catalyst during thermal decomposition provided available diffusion channels for substrates, which facilitated their full contact with catalytic active sites and their effective conversion. The prepared Co@CN catalyst achieved a conversion rate of 100% and a selectivity of 100% in the hydrogenation of quinoline into 1, 2, 3, 4-tetra-hydroquinoline in water at 100 °C under 3 MPa H2. The as-synthesized catalyst had good reuse performance, exhibiting >95% conversion rate and >99% selectivity even after 12 cycles. Moreover, the catalyst could also be applied to the selective hydrogenation of a serial of quinoline derivatives. The study provided a useful strategy for constructing metal-doped carbon materials which might be applicable for other metals and other reactions.