Monsanto Acetic Acid Process

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Monsanto Acetic Acid Process Giana Storck,
Chemistry, Elmhurst College
In this molecular orbital diagram the CO is
donating electrons to the Rh.
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• Some History
• Acetic acid is an industrially important chemical
• During the 19th century, ethanol fermentation
  was used to make the chemical
• Then came an acetaldehyde route to acetic acid
  (using mercury as a catalyst)
• Methanol became an attractive raw material due
  to its relatively low price
• In 1970, Monsanto used this process

Oxidative Addition
CH3I
CH3I
CH3COI
H2O
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HI
CH3OH
CH3CO2H
CO insertion alkyl migration

• Reaction Conditions
• 10-3 M Rh
• 180 C
• 30-40 atm
• gt99 selectivity on methanol
• No hydrogen affect

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The rhodium used for this reaction is used in a
circular fashion, it can be reused.
Coordination of CO
H2O
Reductive elimination
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