4(b) Crude Oil Flashcards
Crude Oil
Mixture of hydrocarbons
How is crude oil seperated?
Fractional Distillation seperates crude oil into fractions
Trends in Fractionating Column (as yu go down the column)
Molecule size, temperature, viscocity, colour INCREASE
Volatility, flammability DECREASE
Order of Fractionating Column
Rare Girl Katie Doesn’t Feed Bitches
Refinery Gases
Gasoline
Kerosene
Diesel
Fuel oil
Bitumen
Uses of Refinery Gases
Domestic Heating
Never condense (removed as vapour)
Uses of Gasoline
Petrol for cars
Uses of Kerosene
Fuel for aircrafts
Uses of Diesel
Fuel for some cars
Uses of Fuel Oil
Industrial oil
Uses of Bitumen
Road Construction
(never reaches its boiling point -> drained off)
How does a fractionating column work?
If a substance is above its boiling point, it will move up the column until the temp. lowers, where it will condense
Fuel
A substance when burned releases energy
Complete Combustion
In excess supply of oxygen
Hydrocarbon + Oxygen -> Carbon Dioxide + Water
Incomplete Combustion
In restricted supply of oxygen
Hydrocarbon + Oxygen -> Carbon Monoxide + Water + (carbon + carbon dioxide)
What is carbon monoxide?
Poisonous, reduces capacity of blood to transport oxygen
What happens in car engines?
Temperature are high enough for nitrogen and oxygen in air to react to form nitrogen oxides
How is sulfur dioxide formed
Combustion of hydrocarbons containing impurities
What do nitrogen oxides and sulfur oxides contribute to?
Acid rain
Cracking
When less useful hydrocarbons are cracked into useful hydrocarbons
Process of Cracking
Long - chain alkanes -> short - chain alkanes + alkenes
Conditions for Cracking
Catalyst: silica or alumina
Temperature: 600-700
Why do oil companies carry out cracking?
Balance between supply and demand
To produce more petrol
To produce for alkenes for polymers (plastics)
Why is cracking needed for supply + demand?
- Too many long chain alkanes which are not in demand/not profitable to sell
- Not enough short - chain alkanes that can be used for cars
