Hydrogenation of aromatics from low temperature coal tar over novel mesoporous NiMoC/Hβ catalysts

The mesopores Hβ-Tx (x = 1, 2, 3, 4, 5) zeolites were synthesized in different crystallization time (48 h, 72 h, 120 h, 168 h, 240 h), and then the NiMoC/Hβ-Tx catalysts were synthesized by equal volume impregnation and programmed temperature carbonization. The effects of crystallization time on the catalytic activity were investigated by hydrogenation of naphthalene, quinoline and aromatics from low temperature coal tar in a fixed bed. The NiMoC/Hβ-T4 catalysts with β zeolite crystallization time of 168 h, exhibited the highest catalytic activity in hydrogenation of aromatics. It can be concluded that higher density of B acid sites of supports, and higher active metal dispersion will enhance the tolerance of catalysts to heteroatoms, while larger grain size of support is unfavorable to resist heteroatoms. Additionally, hydrogenation of aromatics can occur over the prepared NiMoC/Hβ catalysts under mild conditions (275 °C, 3 MPa). The NiMoC/Hβ-T4 catalysts is better than traditional catalysts including NiMoC/Al2O3, NiMoS/Al2O3 and NiMoS/Hβ catalysts in hydrogenation of aromatics.