A aluminosilicate compound with cubic lattices, mainly composed of silicon aluminum and oxygen bridging, which forms an open skeleton structure. There are many pores with uniform pore size and large holes in the structure. In addition, the metal ions and the combined water with a relatively low electric price and a larger ionic radius are also contained. Because the water molecules lose continuously after heating, but the crystal structure unchanged, formed many of the same size and cavity cavity, many of the same diameter pores connected, these tiny hole diameter size uniform, the ratio of the internal pore diameter of small molecules adsorbed to the cavity to the rejection ratio of channels molecular in the outside, so the molecular shape of different diameters, different degrees of polar molecules, molecules of different boiling points, from molecular separation of saturated in different degrees, which has "sieving" molecules, called molecular sieve. At present, molecular sieves are widely used in metallurgical, chemical, electronic, petrochemical, natural gas and other industries.