As the supplies of petroleum diminish, it will become ne­cessary to search for other sources of liquid fuels. Because of the relatively large coal reserves available worldwide, this appears to be the logical source of additional quanti­ties of liquid fuels.

Recently, much attention has been focussed on coal li­quification and as recently as September, 1982, the Divi­sion of Fuel Chemistry of the American Chemical Society sponsored a Symposium on Coal Liquification [7].

In contrast with petroleum, the components of coal, coal liquids and other coal-derived products are primarily aro­matic in nature and as a result present considerably great­er health hazards when produced and handled on a large scale. There have been many different structures proposed for coal.