Filter paper

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Filter paper is a semi-permeable paper barrier used to separate fine substances from liquids or air.


Filter paper consists of a specially designed paper, usually made of high quality cellulose or glass microfibers, with carefully designed pore size. The important parameters of filter paper are wet strength, porosity, particle retention, volumetric flow rate, compatibility, efficiency and capacity.

The filter paper is placed perpendicular in a funnel and the liquid is poured on the filter.


High quality filter paper can be purchased from lab suppliers and online.

Coffee filters can be purchased from most hardware stores.

DIY filter paper

Coffee filters are sufficient, unless you need smaller size pores. Colored coffee filtered may however interact with certain organic solvents. Tea bags are also good and have high wet strength. Note that filtration through tea bag paper is quick and dirty, leaving the finest particles in the filtrate. Air filters can also be used.

Paper towels can be used as filter paper, though their performance is poor.

See also


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