Reactivity 1.3 – Energy from fuels

1.3.4 – Biofuels

📌 Ethanol

  • Used as a liquid biofuel
  • Made from biomass by fermenting plants which are rich sources of carbohydrates
  • This reaction is catalysed by yeast which perform anaerobic respiration which has waste products of ethanol and carbon dioxide
  • Ethanol is then combined with unleaded gasoline (1:9 ratio) to produce a mixture called gasohol
  • Ethanol does have a major disadvantage as it can cause corrosion. Additionally, ethanol forms hydrogen bonds with water molecules in the air which causes it to separate from the hydrocarbons in the mixture

📌 Advantages and disadvantages of biofuels

  • Advantages :
  1. Cheap to maintain & transport
  2. Easily available
  3. Renewable
  4. Sustainable & less polluting
  • Disadvantages :
  1. High cost for harvesting
  2. Lower specific energy than fossil fuels
  3. Uses land