Molecular sieve has two kinds of natural zeolite and synthetic zeolites

Molecular sieve as the powder crystal, with metallic luster, hardness is 3 ~ 5, the relative density of 2 ~ 2.8, the natural zeolite has a color, synthetic zeolite is white, insoluble in water, thermal stability and acid resistance increased with the increase of SiO2 / Al2O3 ratio increased. Molecular sieve has a large specific surface area, 300 ~ 300 m2 / g, the highly polarized crystal surface, as a kind of efficient adsorbent, is also a kind of solid acid, surface has a high concentration of acid and acid strength, can cause is catalytic reaction of carbon ionic. When the composition of the metal ion and other ions in the solution during the exchange, adjustable aperture, change its adsorption properties and catalytic properties, which made the performance of different molecular sieve catalyst.
Molecular sieve has two kinds of natural zeolite and synthetic zeolites
(1) most of the natural zeolite by volcanic tuff and gray matter in the Marine sedimentary rocks coagulation or react to form in the lacustrine environment. Has now found that more than 1000 kinds of zeolite ore, more important is 35 kinds, common clinoptilolite and mordenite, erionite and ling zeolite, etc. Mainly distributed in the United States, Japan, France and other countries, China has also found that there is a lot of mordenite and clinoptilolite deposits, Japan is the largest country in the production of natural zeolite.
(2) by natural zeolite resource limitations, since the 1950 s, the use of synthetic zeolite.