Molecular sieve is a kind of crystallized alumina silicate. As there are even pore size and much more specific surface in it. It has much excellent merit: (1) the selective absorption, according to the size and shape of the absorbed molecule ,in this way, it absorbs only those molecules whose diameter are less than the molecular sieve pore. (2) It has the selective absorption for the polar or unsaturated molecules. The Higher the polarity or unsaturation is , the stronger selective absorption is .(3)It has strong water absorption. Even if higher temperature, larger flow rate and lower water content , it keeps still higher water absorption. Our company has produced many industry molecular sieves, such as 3A,4A,5A,13X and copper-bearing etc.