# Could you separate a colloid by filtering? Explain

If you have a solid in liquid colloid, then it is not possible to separate it by filtration using conventional filter papers as even using the smallest pore size paper you are only just about reaching the maximum particle size of a colloid. Colloids have particle sizes between 1 and 1000 nm (0.001 - 1.0 $\mu$m) and the finest grade filter paper has mean particle size 2 $\mu$m.