When highway cores and hot mixes are extracted, several percent of the asphalt frequently remains on the aggregate. A variety of solvents were evaluated for their ability to remove this material. Theywere compared using several aggregates that had been extracted by three procedures. The effectiveness of alcohols as a solvent additivewas investigated. Finally a direct comparison of trichloroethylene and toluene containing 15% ethanol using an old road-core material was made. In general, trichloroethylene containing 15% ethanol was the best solvent tested. Pyridine is similar but objectionable for other reasons. The residual unextracted material is difficult to removeeven with the best solvents. This paper appears in transportation research record no. 1323, Asphalt mix materials 1991
Abstract