Question

What is ultrafiltration and how is the technique useful in the purification of a colloidal solution?

Answer 1

Ultrafiltration is a filtration technique using ultrafilters, prepared by treating ordinary filter paper to reduce pore size, which allows the passage of impurities but retains colloidal particles. It is useful in purifying colloidal solutions by removing electrolytic impurities while retaining larger colloidal particles. The process can be sped up by applying pressure or suction, and particles of different sizes can be separated using graded ultrafilters.