United States Patent: 4052292
The Mobil Oil technology we report herein is similar in two respects to quite a few others we have previously brought to your attention.
First, as in our recent dispatch concerning: "United States Patent 4,111,787 - Staged Hydroconversion of an Oil-Coal Mixture", which was issued in September, 1978, to Exxon, Mobil herein utilizes a hydrocarbon oil, which can, we submit, be produced via the destructive distillation of Coal, as in a Coke oven, to dissolve more raw Coal into a liquid product that can then be "hydrotreated", and otherwise upgraded, in rather standard petroleum refining facilities, and made thereby to produce conventional liquid hydrocarbon fuels.
Second, in further confirmation of several of our earlier reports, renewable and Carbon-recycling cellulose can be utilized as a raw material, along with Coal, in such direct liquefaction technologies.
But, since Mobil is intent on making this seem to be a process that requires a large amount of conventional petroleum refinery by-product to make it work, some advance notes are in order.
Although Mobil is careful to repeat that products from various stages of oil refining are to be used, they do specify and identify, deep within their text: "polycyclic aromatic hydrocarbon constituents such as naphthalene, dimethylnaphthalene, anthracene, phenanthrene, fluorene, chrysene, pyrene, perylene, diphenyl, benzothiophene, and their derivatives" as suitable solvents for the dissolution of "coal and wood mixtures".