Synthesis Of Ni Nanoparticles Supported On Carbons And Their Catalytic Applications In Hydrogenation Of Coal Tar Pitch

Molecular structures with high aromatic and high condensation is an important issue to hinder the process of high quality mesophase pitch synthesis. Using multiphase-catalytic hydrogenation to bring in the naphthenic structure is an efficient way to improve the spinnability of coal-based mesophase pitch. Carbon-based catalyst has controllable pore structure and surface property, so it is a valuable orientation of coal tar pitch hydrogenation catalyst. In this paper, using coal-based activated carbon and mesoporous carbon as a carrier. Synthesizing the Ni/C catalyst with retting and using the polycyclic aromatic hydrocarbon with 2-4 rings as the model compound. The study works on hydrogenation conversion and yield with the influence of catalyst pore structure, surface property and aromatic molecular structure. Results as following:1. The molecular structure has significant influence of polycyclic aromatic hydrocarbon hydrogenation.Ni@AC is used as catalyst to hydrogenate naphthalene, methylnaphthalene, quinoline, anthracene, phenanthrene and pyrene. By the study of the above reactions, the influence of hydrogenation to model compound of functional group electronegativity and molecular configuration is confirmed. The aromatic hydrocarbon with electrondrawing group like quinoline can improve the hydrogenation reactivity, while the aromatic hydrocarbon with electron-donating group like methylnaphthalene is opposite. Meanwhile, with the condition of this paper, it presents that condensation of polycyclic aromatic hydrocarbon and molecular dimension also play important roles.Regarding pyrene as macromolecule in coal tar pitch and regarding naphthalene, methylnaphthalene, quinoline as small molecule in solvent. The paper studies the interaction in hydrogenation. Increasing the content of naphthalene and quinoline in the miscella can realize the modulation of miscella components and increase the conversion rate of coal tar pitch catalytic hydrogenation and the yield of target product. The average conversion ratio of pyrene increases from 87% to 99% and 97%, and the average yield of target product increases from 32% to 43% and 72% after naphthalene and quinoline are added. Involving the methylnaphthalene, the average conversion ratio of pyrene decreases to 32%, and the average yield of target product decreases to 10.5%.2. Synthesis of new type carbon-based catalyst.In this paper, mid-temperature pitch and quinoline pitch are used as the first type of carbon source, carbonized and activated. MgO is used as mesoporous carbon support catalyst. Synthesizing the Ni/C catalyst with retting and study the influence of hydrogenation with different catalyst and pore structure. When using mesoporous carbon as the catalyst, most of the product is isomeride of pyrene. When using N-doped carbon as the catalyst, most of the product is polymerizate. Bigger pore reduce the inner diffusion resistance. The polycyclic aromatic hydrocarbon has more opportunity to interaction with active site, so there is more side reaction.