Remarkable Oil Yield from an Indonesian Subbituminuous Coal in Liquefaction Using NiMo Supported on a Carbon Black under Rapid Stirring

摘要

Unceasing efforts to cut the cost of coal liquefaction process have been continuing to meet the demand of liquid fuel in the next century. A catalyst that produces higher oil yield at lower cost is recognized as a key to develop such a process. The present authors have proposed NiMo catalyst supported on a particular carbon black of Ketjen Black (KB) which has been proved to exhibit excellent activity for the liquefaction of an American bituminous coal at its recovery from the product by the gravimetric separation based on its hollow sphere of low gravity. The very fine particles of the carbon black around 30 nm provided a large surface for supporting Ni and Mo; however they tend to agglomerate, lowering their contact with substrate. In the present study, the effect of stirring speed on oil yield was examined in the liquefaction of Tanito-harum coal, an Indonesian bituminous coal, because high-speed stirring appears to be very effective to disperse the carbon black particles.