Yoshimasa Inoue

Hydrocracking of Wandoan Coal Liquids (I)

In order to determine the mechanism of hydrocracking of coal liquids, heavy fractions of Wandoan coal liquids were hydrocracked in tetralin solvent containing a small amount of 14C-labeled naphthalene.Wandoan coal liduids were separated into hexane-solubles (HS), toluene-solublehexane-insolubles (HIS-TS) and toluene insolubles (TIS). Hydrocracking of these fractionswas performed with a fixed bed flow microreactor on Ni-Mo-Al2O3 catalyst.Reaction conditions were as follows the temperature was 400°C, pressure 9.8 MPa, H2flow 25 1/h, and WHSV 0 .68/h. The distributions of reaction products and nitrogenconcentrations were determined. The amount of the rehydrogenation of naphthalenesolvent during the hydrocracking was examined by 14C tracer method.The results are summarized as follows;1) When HS was hydrocracked, it was hydrodenitrogenated and hydrocracked to light oil. Furthermore, the rehydrogenation of naphthalene solvent proceeded considerably.2) In the case of hydrocracking of HIS, HS was produced by hydrogenation and denitrogenation of HIS. But the nitrogen content of HIS did not decrease and the solvent was not rehydrogenated.3) In the case of hydrocracking of SRC, HIS was hydrocracked faster than HS, but the hydrocracking of HS and the rehydrogenation of naphthalene solvent did not occur. Therefore, the hydrogenation of each separated fraction is effective to produce light oil.

Change in the catalyst property during the hydrotreating of blended SRC filtrate.

Change in the catalyst property during the catalytic hydrotreating of a blend of 25 percent SRC and 75 percent creosote oil using 0.1 L/h fixed bed reactor has been studied. The results obtained here can be summarized as follows;1) A decrease of the surface area of the catalyst is mainly ascribed to the coke formation.2) Chemical analysis data of used catalysts show that each mineral component accumulates separately, namely, Iron accumulates more at the top of the catalyst bed, but Ca and Ti seem to be deposited uniformly through the catalyst bed. Si deposition is not observed through the bed in this study.3) The mineral components do not penetrate into the particles of catalyst A which has only micropores in the range 4 to 10 nm, and the deposition of these components is observed only around the outer surface of the catalyst particles. On the other hand, in case of catalyst B which has macropores around 60 nm in addition to the micropores, the mineral components can penetrate into the catalyst particles at the upstream part of the reactor, but it seems to be difficult forthem to penetrate into the catalyst particles at the downstream part of the reactor. This different penetration behavior could be due to the particle size distribution of each mineral component.