... hydrogen, carbon oxide, ethylene, propylene. The pore size for 4A molecular sieve is 4A. It can mainly used to adsorb water, methanol, ethanol, sulfureted ... , carbon oxide, ethylene, propylene, does not adsorb any larger molecular than 4A, and often used as desiccant in industries. Formulation: Na2O--Al2O2 ... and unstable material. Desiccant for paint, dope and foul etc. 4A molecular sieves