UW-Madison Demonstration Lab
UW-Madison Department of Chemistry

Groups IA, IIA, IIIB (1, 2, and 13)- The Bayer Process

Explosive Reaction of Hydrogen and Oxygen

Ice Bomb

HCl Cannon

Reduction of Copper Oxide by Hydrogen

Water Gas Reaction

Film of Hindenburg Fire

Relative Reactivity of Alkali Metal With Water

Solution of Sodium in Liquid Ammonia

Extinguishing a Magnesium Fire

Reaction of Aluminum With NaOH

The Bayer Process

The Bayer Process 

Description: A mixture of Aluminum, Silicon and Iron ions in solution may be separated using the amphoteric properties of aluminum to selectively precipitate one species in a mixture. The demo is based on historical industrial processes. 

2 NaAlO2(aq) + 3H2O(l) + CO2(g) → 2Al(OH)3 (aq) + Na2CO3(aq) 

2Al(NO3)3 (aq) + 2CO2(g) + 6H2O(aq) →2Al(OH)3 + 2H2CO3(aq)+ 6NO3–(aq) + H2O(l) 

Al2O3 3H2O(s) + 2Ca(OH)2(aq) + Heat → Al2O3(s) + 2CaO(s) + 4H2O(g) 

Al(s) + 2OH–(aq) +6 H2O(l) → Al(OH)4–(aq) + 3H2(g) 

Solubility section:  

Al(OH)3(s) + 3H+(aq) → Al(H2O)6 +3(aq) + 3H2O(l) 

Al(OH)3(s) + OH–(aq) → Al(OH)4– (aq) 

Na2SiO3(aq) + 2CO2(g) + H2O(l) → Si(CO3)2(s) + 2Na+(aq) 2OH−(aq) 

Sources: Shakhashiri, B.Z., Chemical Demonstrations: A Handbook for Teachers of Chemistry  

Year: 1989   Vol:  3   Page: 128 – 130

Judith Burstyn (2011) Personal Consult 

http://processflowsheets.blogspot.com/2012/05/aluminum-production-process-bayer-hall.html 

Keywords:  Bayer, Acid, Precipitation, Aluminum, Iron, Separation, Silicate 

Rating:

Hazard: Medium

  • Gas under pressure
  • Asphyxiation hazard
  • Serious eye damage
  • Skin corrosion hazard
  • Skin irritation hazard
  • Corrosive to metals
  • Specific target organ toxicity – single exposure – respiratory hazard
  • Acute aquatic toxicity hazard
  • Skin burn hazard
  • Inhalation hazard
  • Frostbite hazard
  • Acute toxicity hazard

Effectiveness: Average

  • Mild effects are observed
  • Time to results is medium
  • Results are observable with guidance
  • Good connection from demo to course material
  • Contrast between systems behavior is noticeable
  • Moderate to  high failure rate

Difficulty:  Medium

  • Use of corrosive reagents
  • Demos at non-standard conditions
  • Multi-step procedures with varying results
  • Some fine manipulations
  • Demos that require some training to perform safely or correctly

Safety Precautions:

  • Gloves required
  • Eye protection required
  • Perform in a well-ventilated area
  • Sodium bicarbonate for spills of strong acid or base
  • Absorbent material on hand
  • Use UL approved three-prong plug and outlet
  • Prevent release of reagents to the environment

 

 

Class: IA, IIA, and IIIB (1, 2, and 13)

Division: Inorganic Chemistry

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