Reactions of small covalent molecules with coal: trifluoroacetic acid

Anhydrous ammonia, methanol, and other protonic reagents have been utilized for the chemical comminution of coal. In this investigation, subbituminous, low-volatile bituminous and high-volatile bituminouscoals have been comminuted readily by trifluoroacetic acid. Approximately 5% of the original coal dissolves during the trifluoroacetic acid treatment leaving a material which has a high calorific value. The pyritic and organic sulphur contents and the ash yields are greatly reduced. Micrographs after treatment show the layered structure of the coal.