Patents by Inventor Roger P. Van Dreisen

Roger P. Van Dreisen 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: RE32265
    Abstract: .[.In a hydrogenation operation employing an ebullated catalytic bed, recycle is recovered from the hydrogenated product with at least 25%, by volume, of the recycle boiling above 950.degree. F. The recycle is cooled to a temperature of from 350.degree. to 600.degree. F. to separate coke precursors, prior to recycle to the hydrogenation. Higher conversion levels can be achieved by effecting recycle in such manner..]..Iadd.Disclosed is a hydrogenation process using at least one fluidized catalytic stage and a recycle material of heavy hydrogenated effluent. The heavy effluent material is cooled to a temperature within 350.degree.-600.degree. F. to separate toluene and heptane insoluble coke precursors prior to recycle. This separation may be enhanced by the use of centrifugation, filtration or a bed of particulate material (e.g. calcined coke). .Iaddend.
    Type: Grant
    Filed: May 17, 1985
    Date of Patent: October 14, 1986
    Assignee: Lummus Crest, Inc.
    Inventors: Harold Unger, Morgan C. Sze, Roger P. Van Dreisen