fractional distillation Flashcards
what is the process by which crude oil can be separated, and briefly how?
fractional distillation- hydrocarbons in crude oil may be separated into fractions, each of which contains molecules with a similar number of carbon atoms
what can the fractions be processed to produce?
fuels and feedstock for the petrochemical industry
give examples of the fuels formed from fractional distillation
petrol, diesel oil, kerosene, heavy fuel oil and liquefied
petroleum gases
give examples of useful materials produced by the petrochemical industry
solvents, lubricants,
polymers, detergents
why do the vast array of natural and synthetic carbon compounds occur?
due to the ability of carbon atoms to form families of similar compounds
describe fractional distillation
- heat the liquid crude oil to a boiling point in a furnace so the compounds vaporise
- the gaseous hydrocarbons enter the fractionating colum then rise up (because hot gas rises)
- as they rise, they cool down, because the top of the column is cooler than the bottom.
- The hydrocarbons will condense when they become cooler than their boiling point, and the liquid hydrocarbons then collect in trays and drain out.
which hydrocarbons leave where and why?
the longer chain hydrocarbons condense at the bottom of the fractionating column because they have high boiling points as they have more intermolecular forces, requiring more energy to overcome
the shorter chain hydrocarbons condense at the top of the column because they have much lower boiling points as they have less intermolecular forces, requiring less energy to overcome
what is the thing called at the bottom of the column?
bitumen
what is the order from top to bottom of the main fuel fractions?
gases
petrol
kerosene
diesel
bitumen
feedstock
a raw material used to provide reactants for an industrial reaction
petrochemical
a substance made from crude oil, via chemical reactions
