What is microfiltration?

What is microfiltration?

Microfiltration is a filtration process using a microporous medium that retains suspended solids in a fluid. The pore size of the membrane ranges from 0.1 to 1 micron or microns.

Microfiltration is different from reverse osmosis and nanofiltration because it does not require pressure. It is often used as a pretreatment for reverse osmosis or as a separate filtration process.

How does it work?

Micro-filtration is a filtration process with a micro-sized filter (μm). The filters can be at atmospheric pressure or with a vessel at a certain pressure (maximum 25 psi) (2), but they usually work at low pressures.

These filters are porous and allow water to pass through them, removing organic matter, suspended solids, small colloids, bacteria and turbidity.

What are the applications of microfiltration?

Microfiltration has many fields of application, such as:

  • Cold sterilization of beverages and pharmaceutical products.
  • Juice, wine and beer clarification.
  • Separation of bacteria from water.
  • As a pre-treatment for Reverse osmosis RO
  • Oil and water separation.
  • Effluent treatment.

Sorting by particle size

Remember that 1 micron (μm) is equivalent to 0.0001 Å.


  1. Huisman, I.H. MEMBRANE SEPARATIONS | Microfiltration. Encyclopedia of Separation Science. s.l. : Academic Press, 2003.
  2. Wes, Byrne. Reverse osmosis. A practical guide for industrial users. Littleton : Tall Oaks Publishing Inc., 2002. 0-927188-03-1.


Last updated 02/12/2020.