industrial manufacturing techniques

• continues process
• batch process

production of aspirin

• ethyl ethanoate and aspirin are produced by a batch process in industry

• in a chemical plant large quantities of reactants are brought together in a reactor during which time the product is produced

• after a certain time the reactor is emptied and the product is separated from the reaction mixture and purified

• the product is then dried and packaged

• esters and their manufacture

  • these have the functional group -COO-
  • they have the name -yl- anote eg methyl methoate
  • both R groups form part of the same

  

esters

• esters are useful products
• used as solvents
• making polyesters
• fruit smells are due to the presence of esters
• ethyl ethanoate is used in glue and nail polish removers
• ethyl ethanoate is used to remove caffeine from tea and coffee

manufacture

• made by reacting ethanol with ethanoic acid
• concentrated sulfuric acid is used as a catalyst
• the reaction is slow and reversable
• CH₃CH₂OH + CH₃COOH → CH₃COOCH₂CH₃ + H₂O
• in industry the ester is made in a batch process
• ethanol and ethanoic acid are added to a large reaction vessel together with the catalyst
• the reaction mixture is heated
• water produced during the rection is removed by distillation
• yields of up to 95% are possible
• other methods
  • Tishchenko reaction
  • liquid phase oxidation of butane
  • alkylation ethanoic acid with ethene (Avada process)

testing methods and techniques

• boiling point determination
• boiling point of pure substances are known very accurately and are listed in databases and books
• the purity of a sample can be determined by comparing the boiling point of the sample to the actual value
• boiling point occurs when the intermolecular bonds are broken
• the greater the difference the more impurities are present
• distillation can be used to determine boiling point
• all values for boiling points are given as standard temperature and pressure