|Class 12 Chemistry Surface Chemistry||Purification of Colloids|
Purification of Colloids
The process used for reducing the amount of impurities to a required minimum is called purification of colloids.
Some of processes used to do so are-
Dialaysis- The process of sepeartaing the particles of a colloid by diffusion through a suitable membrane .
Process – An apparatus called dialyser is used. A bag with a suitable membrane containing the colloid is suspended in a vessel through which fresh water flows continuously. The impurities diffuse through the membrane into the water leaving behind the colloid
Electro-dialysis- Dialysis is a slow method. It is made faster by this method. In this method, an electric filed is applied using metal electrodes. These ions present in the colloidal solution migrate out to the oppositely charge to electrodes. It is possible only if the dissolved substance in the impure colloid is an electrolyte.