Production of ethanol

• What chemical has been discovered for years by people?

  Ethano
• How long ago was ethanol discovered?

  Thousands of years ago
• How can ethanol be produced?

  By fermentation
• What is fermentation?

  Using yeast to convert sugars into alcohol
• What is the chemical equation for fermentation of glucose?

  $C_6H_{12}O_6 \rightarrow 2C_2H_5OH +$$2CO_2$
• What are the products of fermentation?

  Ethanol and carbon dioxide
• From where can carbohydrates come for fermentation?

  From various sources, often sugar beets
• Why are sugar beets often used for fermentation?

  They are cheap and readily available
• What do yeast cells contain that aids fermentation?

  Enzymes
• What do enzymes do in fermentation?

  They speed up reactions
• What are the steps to make a solution of ethanol by fermentation?

  • Mix yeast and a carbohydrate solution (e.g., glucose)
  • Seal the container and keep it warm
  • Maintain the mixture between 20°C and 40°C for fast fermentation
  • Lower temperatures slow down reactions
  • Avoid high temperatures to prevent enzyme destruction
  • Keep the mixture anaerobic (no oxygen)
• What happens when the concentration of alcohol reaches about 10% to 20%?

  Fermentation reactions stop
• What happens to yeast when alcohol concentration is too high?

  Yeast cells get killed off
• What happens to yeast during fermentation?

  They fall to the bottom of the container
• How can you collect the ethanol solution after fermentation?

  From the top of the container
• What can the fermented mixture be distilled to produce?

  More concentrated alcohol
• What is brandy distilled from?

  Wine
• What is whiskey distilled from?

  Fermented grain
• What is vodka distilled from?

  Fermented grain
• What can you collect from the top of the fermentation mixture?

  The ethanol solution
• How can the fermented mixture be distilled?

  To produce more concentrated alcohol
• What is vodka distilled from?

  Fermented grain or potatoes
• What do different types of alcoholic drinks contain?

  Different percentages of ethanol
• What is the typical ethanol concentration of beer?

  About 4%
• What is the ethanol concentration of some spirits?

  About 40%
• What is fractional distillation used for?

  To concentrate ethanol
• How is a dilute solution of ethanol produced?

  By fermentation
• What must be done to create a concentration of ethanol above 20%?

  Ethanol must be concentrated by fractional distillation
• How does fractional distillation separate mixtures?

  By heating them
• What happens to ethanol when the fermentation mixture is heated?

  Ethanol evaporates while water remains
• What is the purpose of a Liebig condenser in distillation?

  To condense vapor back into liquid
• What is the result of cooling the ethanol vapor?

  It condenses into a concentrated liquid
• What is the final product of the distillation process?

  A concentrated ethanol solution
• What are the steps involved in producing concentrated ethanol through fractional distillation?

  1. Heat the fermentation mixture.
  2. Ethanol evaporates while water remains.
  3. Vapor passes through a condenser.
  4. Ethanol vapor condenses into liquid.
  5. Collect the concentrated ethanol solution.
• What are the differences in ethanol concentration among various alcoholic beverages?

  • Beer: about 4% ethanol
  • Spirits: about 40% ethanol
  • Wine: varies, typically around 10-15%
• What is the significance of boiling points in the distillation process?

  • Ethanol has a lower boiling point than water.
  • Allows separation of ethanol from water.
  • Facilitates concentration of ethanol in distillation.
• What is the role of temperature in the distillation process?

  • Heat causes ethanol to evaporate.
  • Water remains as a liquid.
  • Enables collection of concentrated ethanol.
• How does cooling affect the distillation process?

  • Cooling condenses ethanol vapor.
  • Converts vapor back to liquid.
  • Collects concentrated ethanol solution.
• What is the purpose of using a Liebig condenser in distillation?

  • To condense vapor into liquid.
  • Ensures efficient collection of distillate.
  • Maintains temperature control during distillation.
• What happens to the fermentation mixture during heating?

  • Ethanol evaporates.
  • Water remains as a liquid.
  • Facilitates separation of components.