The Effect of Catalyst Concentration, Temperature, and Residence Time on the Chemical Structure of Coal Hydropyrolysis Oils

Abstract

A study was made of the effect that the catalyst concentration, secondly at the effect that the reactor temperature and finally at the effect that the residence time at temperature have on the chemical structure of the oils (hexane soluble product) produced on hydropyrolysis (dry hydrogenation) of a high volatile bituminous coal. Generally, the hydropyrolysis conditions used in this study resulted in oil yields that were considerably higher than the asphaltene yields and this study has been limited to the effect that the three reaction conditions have on the chemical nature of the oils produced. It is found that increasing the catalyst concentration appears to have a wholly beneficial effect on the quality of the oil obtained. The heteroatom content and viscosity are reduced while the gross hydrocarbon structure is little changed. However, for economic reasons high catalyst concentrations are unlikely to be used. Increasing the reactor temperature has both positive and negative effects on the quality of the oil. 18 refs.