explain Mond process ???

The Mond process, sometimes known as the carbonyl process is a technique created by Ludwig Mond in 1890 to extract and purify nickel. The process was used commercially before the end of the 19th century.This process converst nickel oxides into pure nickel.

This process makes use of the fact that carbon monoxide complexes with nickel readily and reversibly to 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 200C to remove oxygen, leaving impure nickel. Impurities include iron and cobalt.

NiO (s) + H₂ (g) → Ni (s) + H₂O (g)

2. The impure nickel is reacted with excess carbon monoxide at 5060C to form the gas nickel carbonyl, leaving the impurities as solids.

Ni (s) + 4 CO (g) → Ni(CO)₄ (g)

3. The mixture of excess carbon monoxide and nickel carbonyl is heated to 220250C. On heating, nickel tetracarbonyl decomposes to give nickel:

Ni(CO)₄ (g) → Ni (s) + 4 CO (g)