Crude oil and fractional distillation

what is crude oil?

a finite resource found in rocks

how is it formed?

formed under extreme high temperatures and pressure from the remains of ancient biomass consisting mainly of plankton that was buried in mud

what is crude oil a mixture of?

very large compounds, however most of these compounds are hydrocarbons

what is feedstock?

raw materials for the petrochemical industry

what do we use feedstock to make?

solvents, polymers, lubricants, detergents

what are petrochemicals?

chemical products derived from crude oil and natural gas via chemical reactions

why do shorter alkanes make the best fuels?

because they have lower boiling points and are more flammable so it requires less energy to burn them for energy

how to carry out fractional distillation of crude oil?

1. heat crude oil so that its components vaporise/ turn into a gas

2. pass the vaporised contents through a fractionating column, and as the vapour condenses it will cool and condense at its boiling point

3. the top of the fractionating column is cooler at the top than at the bottom so the lower boiling point smaller components are at the top (eg. methane)

4. the hydrocarbons with the longest chains have the highest boiling points so they’ll quickly condense back into liquid and remain at the bottom because the top is too cool to keep them in their gaseous states

what are the most flammable fuels produced from fractional distillation of crude oil and their uses?

petrol and diesel - used in vehicle fuel

kerosene - plane fuel

liquified petroleum gas - heating in cooking appliances

what happens to the larger hydrocarbons produced from fractional distillation of crude oil?

they are used for something else or are broken down using cracking into smaller hydrocarbons

why do longer chain alkanes make poor fuels?

because they need high amounts of energy to start combusting

what is heavy fuel oil used for?

boat fuel