Residues (petroleum), steam- cracked naphtha distillation; Cracked gas oil (A complex combination of hydrocarbons obtained as a column bottom from the separation of effluents from steam cracking naphtha at a high temperature. It boils in the range of approximately 147°C to 300°C and produces a finished oil having a viscosity of 18 10^-6 m^2 .s^-1 at 50°C.)