Recycling Aluminum

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Recycling Aluminum

• Chem 1411

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Aluminum ? Alum

• Large amounts of energy are required for the
  production of aluminum from its ores.
• The average lifetime of an aluminum can is 100
  yrs
• Today you will learn how to recycle aluminum to
  make alum.

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Alum

• Alum, aka potassium aluminum sulfate
  dodecahydrate
• It is used in the paper industry, in water
  purification, and for dying fabrics.

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The Process

• React aluminum with a base, KOH
• The base will first attack the oxide layer and
  the excess base will then convert the Al to a
  tetrahydroxoaluminate III ion
• Adding an acid, sulfuric acid,
• The acid removes a hydroxide ion leaving Al(OH)3
  then the excess acid dissolves it forming a
  hydrated aluminum cation

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Procedure Notes

• Smaller pieces of Al will dissolve faster
• When the procedure tells you to heat gently, HEAT
  GENTLY! (heat under the fume hood)
• When using the vacuum filtration system, always
  break the vacuum before turning off the water.
• Use the 9M sulfuric acid under the hood only!!!
• 9M is very concentrated dangerous
• Be Careful!
• Read the directions and pay attention!