Patents by Inventor John G. Ditman

John G. Ditman has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4663028
    Abstract: A process of preparing a donor solvent for coal liquefaction. Liquefied coal is distilled to separate the coal into a fraction having a boiling point less than about 350.degree. F. and a residue having a boiling point greater than about 350.degree. F. The residue from the distillation is deasphalted in a first solvent capable of substantially extracting from the residue a first oil comprising lower molecular weight compounds and saturated compounds. The residue from the first deasphalting step is then deasphalted in a second solvent capable of substantially extracting from the residue a second oil comprising concentrated aromatic and heterocyclic compounds and leaving in the residue asphaltenes and ash. The second oil can be used as a donor solvent. The second oil extracted in the second deasphalting step is preferably partially hydrogenated prior to use as a donor solvent for the liquefaction of coal.
    Type: Grant
    Filed: August 28, 1985
    Date of Patent: May 5, 1987
    Assignee: Foster Wheeler USA Corporation
    Inventor: John G. Ditman