Why can Diesel be separated from crude oil using fractional distillation?

Crude oil is a mix of hydrocarbons which have different boiling points. Larger hydrocarbon molecules and/or chains have higher boiling points as they have stronger intermolecular forces. The mixture of hydrocarbons in crude oil will be filtered out by their different boiling points.The fractional distillation column has a temperature gradient allowing the crude oil vapour to condense at different boiling points. It is cooler at the top so fractions with lower boiling points will condense at the top of the column. The condensed liquids are collected through pipes at different heights. Diesel will condense at a certain temperature and height in the fractional distillation column and be collected.