The holes and channels inside the zeolite crystal are uniform and fixed in size, and the diameter of the holes is generally 6~15A. Honeycomb zeolite molecular sieve Ji'an Only molecules with smaller diameter can enter the cavity through the zeolite channel and be adsorbed, while large molecules cannot enter the cavity and be adsorbed. Zeolite is also called molecular sieve because of its selective adsorption performance. However, silica gel, activated carbon and other adsorbents have no selective adsorption and screening performance due to their non uniformly fixed pore sizes and large changes. Shunyi zeolite filter material price. Because the silicon (aluminum) oxygen tetrahedron of natural zeolite crystal has many holes and channels, which occupy cations and water molecules. When some other goods are completely dehydrated after baking, the crystal skeleton is not damaged, but forms large holes on the inner surface, which can absorb and store a large number of molecules, so it has the characteristics of large adsorption capacity and high selectivity. Honeycomb zeolite molecular sieve purchase In different zeolite minerals, the proportion of silicon and aluminum is different, and the different proportion will cause some characteristics of zeolite changes, such as ion exchange and acid resistance.

Honeycomb zeolite molecular sieve is a kind of aluminosilicate material containing alkali metal or alkaline earth metal oxide with open framework and regular pore cage structure. It has been widely used since it was discovered by Swedish scientists in 1956, and then it has been widely used in petrochemical industry, environmental protection, bioengineering and other fields due to its special physical characteristics. Honeycomb zeolite molecular sieve purchase And with the gradual expansion of the demand for zeolite molecular sieves, researchers began to expand a variety of synthetic methods of zeolite molecular sieves to meet the needs of various fields. Zeolite molecular sieve has super strong adsorption performance, which is due to a "surface force" generated by molecular gravity on the solid surface. When the fluid flows, some molecules in the fluid collide with the adsorbent surface due to irregular movement, resulting in molecular concentration on the surface, reducing the number of such molecules in the fluid to separation Purposes of clearing. Honeycomb zeolite molecular sieve manufactor Since the adsorption does not undergo chemical changes, as long as the molecules concentrated on the surface are managed to drive away, the zeolite molecular sieve will have the adsorption capacity again. This process is the reverse process of adsorption, which is called the resolution or regeneration process.

Molecular sieve has clear pore cavity distribution, extremely high internal surface area (600m2/s), good thermal stability (1000 ℃), and adjustable acid site center. The acidity of molecular sieve mainly comes from three coordinated aluminum atoms and aluminum ions (AlO)+on the framework and in the pores. OH based acid sensitive site center on molecular sieve HY obtained by ion exchange, Honeycomb zeolite molecular sieve Ji'an The aluminum ions outside the framework will strengthen the acid site and form the L acid site center. Polyvalent cations such as Ca2+, Mg2+and La3+can show the acid site center after exchange. The reduction of transition metal ions such as Cu2+and Ag+can also form acid site centers. In general, the higher the Al/Si ratio, the higher the specific activity of OH group. The modification of zeolite acidity can introduce protons through direct exchange of dilute hydrochloric acid. This method often leads to dealumination of molecular sieve framework. So NaY will become NH4Y and then HY. Because there are uniform small internal pores in the molecular sieve structure, when the molecular linearity of reactants and products is close to the pore size of the crystal, the selectivity of the catalytic reaction often depends on the corresponding size of the molecule and pore size. Honeycomb zeolite molecular sieve purchase This selectivity is called shape selective catalysis. There are two mechanisms leading to shape selectivity. One is caused by the difference of diffusion coefficient of molecules participating in the reaction in the pore cavity, which is called mass transfer selectivity; The other is caused by the space limitation of the transition state of the catalytic reaction, which is called transition state selectivity.

Honeycomb zeolite molecular sieve purchase Because the silicon (aluminum) oxygen tetrahedron of natural zeolite crystal has many holes and channels, which occupy cations and water molecules. When some other goods are completely dehydrated after baking, the crystal skeleton is not damaged, but forms large holes on the inner surface, which can absorb and store a large number of molecules, so it has the characteristics of large adsorption capacity and high selectivity. There are cavities and channels in the crystal structure of zeolite with large adsorption capacity, whose volume accounts for more than 50% of the total volume of zeolite crystals. Moreover, the micropores of zeolite are evenly distributed, and the pore size is small, which is equivalent to the molecular size of general substances. The internal surface area of zeolite crystals can reach more than 1000 square meters. Therefore, the adsorption capacity of zeolite is particularly large. Honeycomb zeolite molecular sieve manufactor In different zeolite minerals, the proportion of silicon and aluminum is different, and the different proportion will cause some characteristics of zeolite changes, such as ion exchange and acid resistance.