Performance Characteristics of Asphalt Binders and Mixtures Modified by Waste Toner

Every year, a tremendous amount of toner is produced for copiers and printers by toner manufacturing companies throughout the United States. Some of this toner does not meet quality specifications and becomes a waste of the manufacturing process. This waste and the spent toner from copiers and printer cartridges are dumped in landfills for lack of a better way of utilizing them. A cooperative research project was undertaken by Texas Department of Transportation and the University of Texas to investigate the feasibility and potential benefits of utilizing waste toner in hot mix asphalt concrete. The research program included procurement of a number of different waste toners, blending them with asphalt cement at different ratios, and evaluating binder and mixture properties. The results indicated that as the amount of waste toner in the blend increases, the stiffness and viscosity of the modified binder increase. The mixture analysis also indicates higher strength and stability for toner-modified asphalt concrete compared with unmodified mixtures. The toner-modified binder is expected to perform satisfactorily in areas where permanent deformation is of great concern and some increase in low-temperature stiffness is not regarded as posing any cracking problems. It was found that a PG64-28 asphalt will grade as PG70-22 with the addition of 10 percent waste toner.