process to levels below about 5 ppm for the product light oil thus the economic value of the oil and ease of hydrorefining was much greater than from similar oils produced by pyrolyzing tires at conventional higher temperatures in the 900 u00b0 1400 u00b0 f range where their chloride contents were substantially higher a tire wmo product oil was hydrotreated between about 600 u00b0 750 u00b0 f using a commercial liquefaction catalyst no difficulties were encountered sulfur content was decreased from 1 1 to less than about 0 2 wt in all five samples hydrotreated and as low as 0 08 wt in two samples hydrotreated at 700 u00b0 and 750 u00b0 f nitrogen content remained constant at 0 03 wt while carbon and hydrogen ratios did not change appreciably a base composition of bituminous binder modified with carbonous residue was formulated with 10 wt lt 325 mesh size carbonous residue blended into ac 10 bituminous binder or asphalt however for many situations as little as 5 wt carbonous residue is adequate for mixing laboratory size specimens glass vials sealed with a cone shaped teflon stopper cap assembly were thermally treated for 2 hours in a large aluminum block representing a thermal sink and maintained at 150 u00b0 c at the end of each hour the block assembly housing the vials was mechanically shaken for 5 minutes in a paint shaker after final shaking vials were removed from the block and cooled to ambient temperature without agitation for two hours before commencing any tests when larger quantities of modified binder were prepared the heating mixing period was extended accordingly microscopic examination of modified binders showed ultra fine uniform dispersion of lt 325 mesh size carbonous residue prepared from reactor operating conditions specified earlier conversely pyrolyzed tire residue largely carbon.