A Study of Coal Liquefaction by Coal Model Materials

Abstract

This chapter presents a study of coal liquefaction by coal model materials. The most difficult thing to clarify the mechanism of coal liquefaction is that coal chemical structure is not clear. Coal model materials such as anthracene, dibenzyl, and 1-methylnaphtalene are highlighted in the chapter to discuss the mechanism of coal liquefaction. As per the study described in the chapter, tetralin as solvent is consumed to a maximum in dibenzyl, secondly in 1-methylnaphtalene, and to a minimum in anthracene. On the contrary, the decomposition rate based on the assumption of the first-order reaction is the fastest in anthracene and that dibenzyl is secondary. From these results, liquefaction of anthracene is the fastest, but the produced materials such as dibenzyl is slower than that of anthracene; the produced materials of 1-methylnaphtalene will be lower molecular weights and easy to volatilize. The chapter presents the change of weight loss during liquefaction of the model materials by the pressurized thermobalance. The result of the weight loss meets the assumed mechanism of liquefaction. Aliphatic bridge of coal is reacted, and some lower molecular weight of the reacted productions is volatilized. Aliphatic side chains, especially brief chains, are hard to react, but once reacted, the produced materials will be mainly methane.