Laboratory Filtration is commonly the mechanical or physical operation that is used for the separation of solids from fluids (liquids or gases) by interposing a medium through which only the fluid can pass.
The fluid that passes through is called the filtrate Diagram of simple Laboratory Filtration:
oversize particles in thefeed cannot pass through the lattice structure of the filter, while fluid and small particles pass through, becoming filtrate.
Suction filtration is a chemistry laboratory technique that allows for a greater rate of filtration. Whereas in normal filtration gravity provides the force which draws the liquid through the filter paper, in suction filtration a pressure gradient performs this function. This has the advantage of offering a variable rate depending on the strength of the pump being used to extract air from the Büchner flask. Care must be taken not to use such a strong vacuum that the filter paper rips (in which case all the solid will be lost back into the solvent) or in extreme cases the glass flask breaks.
Vacuum-filtration-diagram:
VACUUM FILTRATION SET,COMPLETE SYSTEM, 3 PLACES