CHARACTERIZATION OF CIRCLE CLIFFS OIL SANDS OF UTAH

In the continuing characterization studies of Utah oil sands, this art icle was focused on the Circle Cliffs deposits which occur in the sout heastern region of Utah. The bitumen was separated from the oil sand u sing a toluene extraction method. The extracted bitumen was fractionat ed using the modified SARA method and its fractional composition was c ompared to the other bitumens obtained from the Uinta Basin deposits. This comparison indicated that Circle Cliffs bitumen was unique among the Utah oil sand bitumens, particularly with respect to the chemical composition of its resin fraction, but showed resemblance with the Can adian Athabasca bitumen in some features. The effect of resin composit ion on the bitumen viscosity is discussed. Mineralogical analysis was performed on the solids, which indicated relatively large proportions of carbonate and kaolinite minerals. The undesirable effect of these m inerals in the modified hot-water processing of Circle Cliffs oil sand s is briefly discussed.