Molecular sieves are used for drying gases and liquids and for separating molecules on the basis of their sizes and shapes. When two molecules are equally small and can enter the pores, separation is based on the polarity (charge separation) of the molecule, the more polar molecule being preferentially adsorbed.

How do molecular sieves remove water?

Molecular sieves are crystalline metal aluminosilicates having a threedimensional interconnecting network of silica and alumina tetrahedra. Natural water of hydration is removed from this network by heating to produce uniform cavities which selectively adsorb molecules of a specific size.

How does molecular sieve work?

A molecular sieve works by adsorbing gas or liquid molecules that are smaller than the effective diameter of its pores, while excluding those molecules that are larger than the openings. ... The size of the pores of both Type A and Type X molecular sieves is closely controlled during the manufacturing process.