Nickel nanoparticles embedded in porous carbon-coated honeycomb ceramics: A potential monolithic catalyst for continuous hydrogenation reaction

The preparation method of porous carbon coated honeycomb ceramic monolithic catalysts is limited to traditional ideas. The porous carbon and the active metal particles are formed step by step. We have designed a novel preparation method and constructed a series of nickel-embedded porous carbon-coated ([email protected]) monolithic catalysts with different carbonization temperatures. Through the synchronous formation of porous carbon and active metal particles, the relationship between porous carbon and metal is changed from "supported" to "embedded". The "embedded" structure between nickel particles and porous carbon formed at suitable carbonization temperature is an inseparable whole. Correlation characterization results show that the "embedded" structure has not changed the physical-chemical properties of porous carbon. However, the effect on the physical-chemical properties of nickel particles is very significant. Compared with conventional supported nickel-based monolithic catalysts (NiO/C), embedded nickel particles in the [email protected] monolithic catalyst have four characteristics. They are more uniform particle dispersion, smaller average particle size, more difficult to migrate and stable in metallic Ni0 form in air. Based on these advantages, [email protected] monolithic catalysts show better catalytic activity, stability and convenience in the continuous catalytic hydrogenation of aromatic nitro compounds.