What is the material of ro membrane (reverse osmosis membrane) in Smith water purifier?

Reverse osmosis membrane is an artificial semi-permeable membrane with certain characteristics, which is made of polymer materials. Such as cellulose acetate film, aromatic polyhydrazide film and aromatic polyamide film.

The structure of reverse osmosis membrane includes asymmetric membrane and homogeneous membrane. At present, the main membrane materials used are cellulose acetate and aramid fiber. Its components are hollow fiber type, roller type, plate frame type and tube type.

Extended data:

Reverse osmosis membrane can intercept inorganic molecules such as soluble salts and organic substances with molecular weight greater than 100. On the other hand, water molecules can freely permeate through the reverse osmosis membrane, and the typical soluble salt removal rate is >: 95~99%. The working pressure ranges from 7 bar (100psi) when the inlet water is brackish water to 69 bar (1 000psi) when the inlet water is seawater.

Nanofiltration can remove impurities with a particle size of 1nm( 10 angstrom) and organic substances with a molecular weight of more than 200 ~ 400. The removal rate of soluble solids is 20 ~ 98%, and the removal rate of salts containing monovalent anions (such as NaCl or CaCl2) is 20 ~ 80%.

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