A new method was developed and proved to be effective in substantially removing hydrocarbon contaminants (asphaltic materials) from bituminous sands (tar or oil sands). Ultrasonication was used in the removal in presence of an alkaline aqueous solution at ambient temperature and atmospheric pressure. Bituminous sand samples used were primarily from the large known Athabasca deposits from which these energy source matrices have recently been explored as an alternative to petroleum. It is anticipated that this new technology may alleviate the environmental problems of existing operations (e.g., the tailing ponds), at the same time produce bitumen in the most efficient manner.

The process reactions which proceed by self-propagating surfactant mechanisms utilize the principles of both membrane-mimetic and free-radical chemistry. By applying ultrasonic energy and traces of a free-radical initiator the reaction rate was enhanced from days to minutes time. Cavitation induced by ultrasonic frequency alters the bulk of the chemical structures of contaminants through cracking at selected aromatic sites leaving the backbone intact. Free-radicals react with other more susceptible reactive chemicals and catalyze the formation of lighter and more desirable hydrocarbon fractions. At the same time, the heavier and highly condensed aromatic compounds complexed with the metals separate through micellar inversion process followed by precipitation.

In order to elucidate the extent of removal of hydrocarbon contaminants within the process for a better understanding of reaction mechanisms and possible future optimum reactor design in a larger scale, many representative experiments were conducted and several combinations of reactants and products were carefully investigated. Experimental results demonstrated that the bitumens recovered were extraordinarily low in asphaltic and metal contents, possessing on average gravities of about 15$\sp\circ$AP1 for high cumulative recoveries. The middling of the process was virtually recycleable for as long as the solution pH remained above 10. Addition of free-radical initiators increased the reaction rate by as much as 20 fold. It was shown that the dynamics of contaminant removal can be simulated in an autocatalytic fashion. This general work may be applied to control the environmental contaminants. (Copies available exclusively from Micrographics Department, Doheny Library, USC, Los Angeles, CA 90089-0182.)