Small block activated carbon purchase The mutual adsorption between molecules is also called "van der Waals gravity". Although molecular motion speed is affected by temperature, material and other reasons, it always keeps moving in the micro environment. Due to the mutual attraction force between molecules, when a molecule is trapped in the inner pore volume of zeolite, it will lead to more molecules being absorbed until the adsorption of zeolite is saturated. Physical adsorption mainly occurs in the process of removing impurities from the liquid and gas phases of zeolite. The porous structure of zeolite provides a large amount of specific surface area, which makes it very easy to absorb and collect impurities. Due to the interaction of molecules, a large number of molecules on the pore wall of zeolite can generate strong gravity, just like magnetic force, So as to achieve the purpose of attracting impurities in the medium to the aperture. Small block activated carbon Hunan Chemical adsorption In addition to physical adsorption, chemical reaction also often occurs on the surface of zeolite, which contains a small amount of chemical combination, oxygen and hydrogen in the form of functional groups. These surfaces contain oxides of earth or complexes that can react with the adsorbed substances, and then combine with the adsorbed substances to gather inside and on the surface of zeolite.

Because there are uniform small internal pores in the molecular sieve structure, Small block activated carbon Hunan When the molecular linear degree of reactants and products is close to the pore size of the crystal, the selectivity of catalytic reaction often depends on the corresponding size of the molecule and pore size. 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. 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. The OH based acid sensitive site center on the molecular sieve HY obtained by ion exchange, and the aluminum ion outside the framework will strengthen the acid site, forming 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. Small block activated carbon purchase This method often leads to dealumination of molecular sieve framework. So NaY will become NH4Y and then HY.

purchase Small block activated carbon The pore size of zeolite is uniform, the internal void structure is developed, the specific surface area is large, the adsorption capacity is strong, and contains a large number of invisible pore sizes. The pore size in 1g zeolite material can be expanded to the specific surface area of 500-1000m2, which is higher for special purposes. The main material of honeycomb zeolite adsorbent is natural zeolite. The zeolite manufacturer is an inorganic microporous material composed of sio2, al_2o_3 and alkaline metal or alkaline earth metal. Its inner pore volume accounts for 40-50% of the total volume, and its specific surface area is 100-500 m2/g, Small block activated carbon Hunan It has the characteristics of high temperature resistance, incombustibility, good thermal stability and hydrothermal stability. It is an efficient molecular sieve carrier with good adsorption performance, no secondary pollution, and can be regenerated at high temperature. Compared with honeycomb activated carbon, its performance is about 25% of its efficiency. However, it has the characteristics of high temperature resistance, difficult ignition, etc. It is widely used in the fields of adsorption, separation, catalysis and environment, and is more suitable for large air volume Low concentration organic waste gas treatment.

Small block activated carbon purchase Due to its large pore size, mesoporous materials have become a good carrier for molecular reaction with large size. However, the pore wall of mesoporous materials is amorphous, so their hydrothermal stability and thermal stability cannot meet the harsh conditions required for petrochemical applications. Because there are metal ions with low electricity price and large ion radius and water in the combined state, water molecules are continuously lost after heating, but the crystal skeleton structure remains unchanged, forming many cavities with the same size. The cavities are connected by many micropores with the same diameter. These tiny holes have uniform diameters, which can adsorb molecules smaller than the diameter of the hole into the interior of the hole, By excluding molecules larger than pores, molecules with different shapes, diameters, polarities, boiling points and saturation levels can be separated, Small block activated carbon manufactor It has the function of "screening" molecules, so it is called molecular sieve. At present, molecular sieves are widely used in metallurgy, chemical industry, electronics, petrochemical industry, natural gas and other industries.

Molecular sieve is a crystalline silicate or aluminosilicate, which is a pore and cavity system with molecular size (usually 0.3nm to 2.0nm) formed by connecting silicon oxygen tetrahedron or aluminum oxide tetrahedron through oxygen bridge bond, Small block activated carbon Hunan Therefore, it has the characteristics of screening molecules. However, with the deepening of molecular sieve synthesis and application research, researchers have found phosphoaluminate molecular sieves, and the skeleton elements (silicon or aluminum or phosphorus) of molecular sieves can also be replaced by B, Ga, Fe, Cr, Ge, Ti, V, Mn, Co, Zn, Be and Cu, and the size of its pores and cavities can also reach more than 2 nm, Small block activated carbon purchase Therefore, molecular sieves can be divided into silicon aluminum molecular sieves, phosphorus aluminum molecular sieves and skeleton heteroatom molecular sieves according to the composition of skeleton elements;

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, Small block activated carbon Hunan 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. Small block activated carbon 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.