Membrane is a material with functions of selectivity and separation. The process of using membrane’s selectivity to separate the different component of liquid is known as membrane separation. It is different from the traditional filtration due to the membrane can isolate liquid in molecular range, and this process is a physical separation, without either phase change or using any additives.

Membrane filtration separates out the different components in a feed stream on the basis of the size and shape of the micro-particles within it. And the better the filtration, the better the quality and value of your end product. This separation takes place by pumping the feed stream across the surface of a membrane with pores so microscopic that they are measured in angstroms (1 x 10^-10 m). Some components pass through – others cannot. Membrane filtration is often used to supplement conventional centrifugal separation processes based on gravity differences. Membrane filtration can also be used for concentration prior to evaporation and spray drying.