4A molecular sieve is a kind of alkali aluminosilicate,able to adsorb moleclars with their critical diameters no more than 4A.it can adsorb H2O,NH3,H2S,SO2,CO2,C2H5OH,C2H6,C2H4,C3H6,etc.it is widely used in the drying of gases and liquids,or used in refining and purification of some gases or liquids,such as production of Ar.

Physi-chemical indexes:
Size,mm                                            1.5-1.7      3.0-3.3      2-3          3-5
Abrasion rate,% <                                0.30         0.50         0.35         0.35
Bulk density >                                       0.6           0.6           0.6           0.6
Static water absorption,% >                   20.5          20.5         21            21