Define van arkel method and froth …

• This method is extensively employed for the preliminary treatment of the minerals especially sulphides ore
• The process is based on the difference in wetting characteristics of the gangue and the ore with water and oil
• The gangue surface being wetted by water and of ore surface the by oil
• The crushed ore along with water (slurry) is taken in a floatation cell
• The impure crushed ore is taken in the big tank provided the resulting mixture is agitated vigorously by passing compressed air through a perforated pipe
• The ore particles are preferentially wetted by oil which rises up to the surface with froth or foam formed by the oil and air
• The gangue impurities being wetted by water settle to the bottom of the tank. The foam gets transferred to the other side of the tank where it slowly subsides
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Van Arkel Method:

• This is used for getting ultra pure metals
• The principle involved is to convert the metal to a volatile unstable compound and to subsequently decompose it to give the pure metal
• Metals like titanium, zirconium are purified by using this method