Noble Metal Nanoparticles Supported On Mesoporous Carbon Materials Derived From Metal-organic Frameworks As Catalysts For Selective Hydrogenation Reactions

Hydrogenation is one of the most significant process in chemical and petroleum industry.With the development of nano-materials in recent years,traditional catalysis in industrial areas is more tightly combined with nano-materials.As for the superiorities of minute dimension,high surface area and excellent catalytic activity,nano-materials are widely applied in catalysis.Metal-Organic Frameworks,one of the complex compounds,possesses 3D pore structure and high surface area,having been rapidly developed in recent decade and become another important type of materials besides zeolite and carbon nanotube.Preparation of carbon materials through direct carbonization of MOFs combines the advantages of simple procedure,uniform morphology and heritage of pore structure and metal elements in MOFs,thereby being widely concentrated by researchers.In the work involved in this thesis,different mesopore carbon materials were successfully prepared by direct carbonization of different MOFs and noble metal nanoparticles including palladium and ruthenium were supported on these carbon materials.The as prepared catalysts were tested in selective hydrogenation of pheneacetylene and other types of alkynes and halonitrobenzenes,exhibiting excellent catalytic activity and selectivity.1.Palladium nanoparticles immobilized on magnetic porous carbon derived from ZIF-67 as efficient catalysts for the semihydrogenation of phenylacetylene under extremely mild conditionsZIF-67 was prepared through hydro-thermal method,and was carbonized under high temperature and protection of nitrogen to prepare cobalt nanoparticles embedded carbon materials in which the Pd nanoparticles were well dispersed.The designed catalysts(Pd-MDPC)were tested in the semihydrogenation of phenylacetylene under extremely mild conditions,exhibiting high catalytic activity and selectivity towards olefins.The Pd-MDPC catalysts were further investigated in the semihydrogenation of several other terminal alkynes.Compared with most traditional carbon materials,such as activated carbon and carbon nanotubes,our catalyst possesses an admirable magnetism so that it could be separated magnetically from the reaction system.2.Ru nanoparticles supported on nitrogen-doped porous carbon derived from ZIF-8 as an efficient catalyst for the selective hydrogenation of p-chloronitrobenzene and p-bromonitrobenzeneNitrogen-doped porous carbon was synthesized by one-step carbonization of ZIF-8,maintaining uniform morphology,high surface area and stable chemical-physical properties.Ru NPs were supported by different methods.Four types of Ru-based catalysts are tested in the selective hydrogenation of p-chloronitrobenzene(p-CNB)and p-bromonitrobenzene(p-BNB)to haloanilines.Different catalytic activities and selectivities are obtained through these catalysts.After the screening of the catalysts and reaction conditions,high conversion and selectivity were obtained.The hydrogen pressure is limited to 1.5 MPa,which is much lower than most previous reports,and the dehalogenation reaction is restricted to a very low level.Furthermore,the dehalogenation properties of the Ru/NPC catalysts are also studied.