Abstract Used tyres were thermally decomposed under vacuum in a process development unit. At 510°C and total pressure 2–20 kPa, the process yielded 50 wt% oil, 25 wt% carbon black, 9 wt% steel, 5 wt% fibres and 11 wt% gas. Distillation of the pyrolytic oil yielded ∼20 wt% light naphtha (i.b.p. 160°C), 6.8 wt% heavy naphtha (160–204°C), 30.7 wt% middle distillate (204–350°C) and 42.5 wt% of bottom residue (>350°C). d,l-Limonene was one of the major chemicals in the naphtha fraction, with a concentration of ∼7 wt%. The naphtha also had high contents of aromatics, olefins and iso-alkanes (45, 22 and 15 vol. % respectively). Its relatively high levels of sulfur, nitrogen, olefinic and diolefinic compounds would make it unsuitable as a blending component for gasoline without hydrofining and reforming. However, ∼2 vol. % of the naphtha could be blended with hydrofiner feedstock without significantly affecting the process requirements. Approximately 71.1 and 68 wt% of the pyrolytic and petroleum light naphthas respectively were quantified.