Filtration is the mechanical-physical operation
which is used for the separation of solids from fluids (liquids or gases)
by interposing a porous media through which only the fluid can pass.
Oversize solids in the fluid are retained on the surface as well as
within the matrix of the filter media.Filtration has a wide range of
applications: from laboratory analytical procedures to techniques in
big production lines.
Guidance to use the correct filter
Quantitative and qualitative analysis |
General laboratory procedures (clarifying filtration) |
Technical applications |
Special applications |
Very small particles |
Aggressive substances |
Temperatures up to 1000 ºC |
Water analysis |
Biochemical determinations |
Air monitoring |
As membrane pre-filter |
Extraction solid/liquid with Soxhlet |
Powder and aerosol particles collection in gases |
Filter papers retain the impurities or particles of the liquid fluids on the surface as well as within the matrix of the filters. The particles or impurities are settled into the filter, modifying its filtration properties. Within the filter fibers arranged in an anarchic way into the filter paper, it creates a secondary filtration layer. This is the reason why it is not possible to determine a nominal porosity for the filter papers. As guidance it is possible to find the retention ranges into our technical specifications tables. Often the filter papers are named as depth filters; they have a high capacity to retain particles and allow process big quantities of sample.