The dehydration principle of molecular sieves is based on the selective adsorption of water molecules 

by its microporous structure. Water molecules are polar molecules, and the pore walls of molecular sieves 

are composed of silicon-oxygen tetrahedrons and aluminum-oxygen tetrahedrons. The charge distribution 

of these tetrahedrons is uneven, resulting in a certain polarity on the surface of the pore wall. Therefore, 

water molecules can be adsorbed by the pore walls of the molecular sieve and form hydrogen bonds within 

the pores. When gas containing water molecules passes through the molecular sieve, the water molecules 

will be adsorbed by the pore walls of the molecular sieve, while other molecules cannot enter the micropores 

of the molecular sieve. In this way, water molecules are separated from the gas, thereby achieving the purpose 

of dehydration.

In addition, molecular sieve dehydration also takes advantage of the characteristic that the equilibrium 

adsorption capacity of the adsorbent decreases as the temperature increases, and adopts the operating 

methods of normal temperature adsorption and heating desorption to achieve the separation of different gases.

The above content is for reference only. If you need more information, it is recommended to consult relevant literature 

or consult professionals.