The final boiling point (FBP), in contrast, was much lower in the
biodiesel than in diesel. They were 348 C and 387 C for the biodiesel
and for diesel, respectively. The lower FBP for the biodiesel
was because the double bond of unsaturated of alkyl chains could
be polymerised at high temperatures. This, therefore, hindered the
volatilization of liquid at the end of the distillation process, which
could lead to the formation of gums, carbon residue in the nozzles
or on the surface of pistons causing corrosions.