CHEM Fuels and Crude Oil

Fuels and Crude Oil

Importance of Natural Gas and Crude Oil

  • Natural gas and crude oil are non-renewable energy sources.
  • Crude oil is a mixture of hydrocarbons.
  • Fossil fuels, including natural gas, are vital for electricity generation.
  • Burning fossil fuels converts chemical energy into thermal energy, which can be converted to other forms of energy.

Natural Gas

  • Natural gas is a fossil fuel consisting mainly of methane (CH4)(CH_4).
  • Combustion equation: CH<em>4(g)+2O</em>2(g)→CO<em>2(g)+2H</em>2O(g)CH<em>4(g) + 2O</em>2(g) \rightarrow CO<em>2(g) + 2H</em>2O(g)
  • Natural gas is transported in liquefied form at -162°C.
  • Tetrahydrothiophene (THT) is added to natural gas to detect leaks.

Crude Oil

  • Crude oil is a mixture of hydrocarbons extracted from beneath land and ocean floors.
  • It needs to be separated into different groups of hydrocarbons before use.
  • Natural gas and crude oil are non-renewable energy sources that take millions of years to form and are being depleted rapidly.

Separation of Crude Oil

  • Crude oil is separated by fractional distillation due to different boiling points of hydrocarbons.
  • Fractional distillation involves boiling and condensation.
  • Smaller hydrocarbon molecules with fewer carbon atoms are collected at the top of the fractionating column (lower boiling points).
  • Larger hydrocarbon molecules with more carbon atoms are collected at the bottom of the column (higher boiling points).

Biofuels

  • Biofuels are renewable alternatives to natural gas and crude oil.
  • Ethanol from sugarcane is a biofuel.
  • Biofuels are more environmentally sustainable due to carbon dioxide offset during plant growth.
  • Combustion equation for ethanol: CH<em>3OH(l)+3O</em>2(g)→2CO<em>2(g)+3H</em>2O(g)CH<em>3OH(l) + 3O</em>2(g) \rightarrow 2CO<em>2(g) + 3H</em>2O(g)
  • Fossil fuels have a greater environmental impact than biofuels.