Mond's Process

It is a technique created by Ludwig Mond in 1899 to extract and purify nickel. It is done by converting nickel oxides (nickel combined with Oxygen) into pure nickel

This process makes use of the fact that carbon monoxide complexes with nickel readily and reversibly give nickel carbonyl. No other element forms a carbonyl compound under the mild conditions used in the process.

This process has three steps:

1. Nickel oxide is reacted with syngas at 200 °C to remove oxygen, leaving impure nickel. Impurities include Fe and Co

NiO (s) + H₂ (g) → Ni (s) + H₂O (g)

2. The impure nickel is reacted with excess carbon monoxide at 50 - 60 °C to form tetracarbonyl nickel.

Ni (s) + 4 CO (g) → Ni(CO)₄ (g)

3. The mixture of excess carbon monoxide and nickel carbonyl is heated to 220 - 250 °C. On heating, tetracarbonyl nickel decomposes to give nickel:

Ni(CO)₄ (g) → Ni (s) + 4 CO (g)