Answer:
fractional distillation
Step-by-step explanation:
The technique used in the separation of complex hydrocarbon mixture based on the boiling points of the different components of the mixture would be fractional distillation.
Fractional distillation is a method of separation involving liquid mixtures. The technique utilizes the difference in the boiling points of each liquid component of the mixture to distillate it into fractions within a fractionating column.
The process involves heating the mixture. Once the temperature gets to the boiling point of one of the components of the mixture, the component vaporizes and condenses out in the fractionating column. Each of the components keeps fractionating out based on their temperatures until all the components have been separated.