molecular sieve drying,drying molecular sieve

molecular sieve drying is amorphous silicate or silicon aluminate, made of silicon oxygen tetrahedron or alumina tetrahedron by oxygen bridge is linked together to form a molecular size (usually from 0.3 to 0.3 nm) of concreted complete cavity system, which are characteristic of molecular sieve. However, with the deepening of the molecular sieve synthesis and application research, the researchers found that the phosphorus aluminate salts drying molecular sieve, molecular sieve and the skeleton of elements (silicon or aluminum or phosphorus) can also Be composed of B, Ga, Fe, Mn, Cr, Ge, Ti, V, Co, Cu and zinc, Be replaced, the concreted complete cavity also can achieve more than 2 nm, the size of the molecular sieve can Be divided by skeleton elements silicon aluminum type molecular sieve, phosphorus kind of molecular sieve and skeleton heteroatomic molecular sieve; According to the hole size, hole size less than 2 nm, 2 ~ 50 nm, and more than 50 nm molecular sieve respectively called microporous and mesoporous and macroporous molecular sieve. With large aperture, become a good carrier of larger molecular reaction, but for amorphous mesoporous materials of hole wall, causing its water thermal stability and thermal stability is not required for petrochemical industry application harsh conditions

natural gas adsorbent,molecular sieve separation

natural gas adsorbent is a kind of crystal type of aluminum silicate, the crystal structure of neat and uniform pore size was in the order of molecular size, it only allows molecules into the smaller than the aperture diameter, so can according to the size of the molecules in the mixture screening. According to molecular sieve. As early as 200 years ago, b. g dragon, he named the first molecular sieve separation, the chemical composition in the general formula for molecular sieve zeolite molecular sieve type M and n are metal ions and the valence; X is the silica on the number of molecules; Y is the number of molecules of water; P is aluminum atomic number; Q is number of silicon atoms. Molecular sieves in chemical industry as a solid adsorbent, by adsorption material can desorption, molecular sieve can be recycled after use. Is also used in gas and liquid, dry, purification, separation and recycling. In the 1960 s, used as cracking catalysts in the petroleum refining industry, has now developed a variety of suitable for different molecular sieve catalysts for catalytic process.

Summary of the dangers of molecular sieve xh-7

Health hazard: the goods for the central nervous system inhibitors. First cause excitement, then inhibition. Develops in oral acute poisoning: molecular sieve xh-7 acute poisoning. Generally can be divided into the excitement, four stage hypnosis, anesthesia, and suffocation. Into the third or fourth stage, patients with loss of consciousness, pupil dilation, irregular breathing, shock, heart failure and stop breathing cycles. Chronic effects: molecular sieve dryer high concentration of the goods in the production of medium and long-term contact can cause nose, eyes, mucous membrane irritation, and headache, dizziness, fatigue, easily excited, tremor, nausea, etc. Found for a long time can cause multiple neuropathy, chronic gastritis, fatty liver, liver cirrhosis, myocardial damage and organic psychosis and so on. Long-term exposure can cause dry skin, desquamation, cracked and dermatitis.

Combustion hazard: the goods flammable, stimulative.

Preparation of molecular sieve xh-5

Until the 1930 s, fermentation is the only industrial molecular sieve xh-5 production methods. With the rapid development of petrochemical industry, synthesis of ethanol production is more and more big. But in the synthesis of ethanol mixed heterogeneous high carbon molecular sieve xh-9, to the person's senior neural paralysis, not suitable for used as a beverage, food, medicine, spices, and so on. Therefore, even in the petroleum chemical industry developed countries, fermentation of ethanol still occupies certain proportion.

double glazing molecular sieve in physical applications

double glazing desiccant molecular sieve is an important organic solvent, which are widely used in medicine, paint, health supplies, cosmetics, grease, and other methods, accounting for about 50% of the total consumption of ethanol. double glazing molecular sieve is an important basic chemical raw materials, used in the manufacture of acetaldehyde and ethyl diene, ethylamine, ethyl acetate, acetic acid, ethyl chloride, etc., and derived the medicine, dye, coating, spices, synthetic rubber, detergent, pesticide and so on many of the intermediate products, the products up to more than 300, ethanol intermediate in chemical products use is decreasing gradually, many products such as acetaldehyde, acetic acid, ethyl alcohol is no longer using ethanol as raw materials and other raw materials instead. 75% ethanol aqueous solution has strong sterilization ability, is a common disinfectants. Can be used to make ethanol from specially prepared drinks. Similar to methanol, ethanol can be used for energy. Some countries have begun to separate using ethanol as fuel or mixed into gasoline (10%) used to save petrol.

molecular sieve xh-11

molecular sieve xh-11 Also known as anhydrous alcohol, refers to the ethanol concentration is greater than 99% (mass). Mainly used as solvent for cosmetics, pharmaceutical and other industries. Supreme general of industrial ethanol concentration of 95%. To obtain anhydrous ethanol, may be further desiccant for insulated glass with the following three ways: (1) treated with lime industrial ethanol, make water into insoluble calcium hydroxide, ethanol, and then steamed out with sodium metal is dry, it is the old way. (2) the azeotropic distillation dehydration is a commonly used method in industry at present. Generally with benzene as azeotropic agent, steamed out of a boiling rectification tower over the course of the first, benzene, ethanol and water ternary azeotrope, again in the second azeotropic distillation steamed out binary azeotrope of benzene and ethanol, the steam out of the anhydrous ethanol in alcohol distillation. Because of the benzene in the product and about 0.5% (mass) of the residual, and benzene toxicity is bigger, has developed in recent years is pentane or hexane instead benzene as azeotropic agent. (3) with ion exchange agent or molecular sieve dehydration, then distillation.

The kinds of molecular sieve xh-7

molecular sieve xh-7 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 been found that there are more than 1000 zeolite ore, more important is 35, common clinoptilolite and mordenite, erionite and ling zeolite, etc. Mainly distributed in the United States, Japan, France and other countries, China is 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 constraints, starting in the 1950 s, a large number of the synthetic zeolite.

Commodity molecular sieve dryer common prefix digital classifying crystalline structure of different molecular sieves, such as 3 a, 4 a, 5 a molecular sieve. 4 A type or class A in the table, aperture 4 A. . Type A molecular sieve as containing Na + Na - A, if one was Na + K + displacement, pore diameter of about 3 A; For type 3 a molecular sieve; If there is more than A third in the Na - A Na + Ca2 + displacement, pore diameter of about 5 A; , that is, the type of 5 a molecular sieve.

The performance of the molecular sieve dryer

molecular sieve dryer 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 xh-5 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 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.

The kinds of molecular sieve xh-7

molecular sieve dryer 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 been found that there are more than 1000 zeolite ore, more important is 35, common clinoptilolite and mordenite, erionite and ling zeolite, etc. Mainly distributed in the United States, Japan, France and other countries, China is 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 constraints, starting in the 1950 s, a large number of the synthetic zeolite.

Commodity molecular sieve xh-7 common prefix digital classifying crystalline structure of different molecular sieves, such as 3 a, 4 a, 5 a molecular sieve. 4 A type or class A in the table, aperture 4 A. . Type A molecular sieve as containing Na + Na - A, if one was Na + K + displacement, pore diameter of about 3 A; For type 3 a molecular sieve; If there is more than A third in the Na - A Na + Ca2 + displacement, pore diameter of about 5 A; , that is, the type of 5 a molecular sieve.

The working principle of double glazing desiccant molecular sieve

Adsorption function: double glazing desiccant molecular sieve of matter from the physical adsorption (van der Waals force), the crystal inside the cavity has a strong polarity and coulomb field, the polar molecules (water) and unsaturated molecules exhibit strong adsorption ability.

Sieving function: double glazing molecular sieve pore size distribution is very uniform, only the molecular diameter smaller than the diameter of the cavity material made it into the zeolite crystal inside the cave.

Through adsorption priorities and the size to distinguish between different materials of molecules, so the image of a called "molecular sieve".

Functions and features of

Porous materials has been widely used in many fields, such as microporous molecular sieve xh-11 as the main catalytic materials, adsorption materials and ion exchange separation materials, in oil processing, petrochemical industry, fine chemical industry and daily chemical industry plays a more and more important role.

desiccant for insulated glass (also called synthetic zeolite) is a kind of silicon aluminate microporous crystals. It is composed of silica and alumina tetrahedron basic skeleton structure, there is a metal cation in the lattice (such as Na +, K +, Ca2 +, Li +, etc.), to balance the extra negative charge in the crystal. Molecular sieve type according to its crystal structure is mainly divided into: type A, X, Y, etc.

Molecular sieve relevant standards:

The 3 a molecular sieve, the 4 a molecular sieve 5 a molecular sieve and its test method, the 13 x molecular sieve

Molecular sieve static water adsorption method, the measuring method of the molecular sieve adsorption dynamic water"

The determination of zeolite molecular sieve adsorption dynamic carbon dioxide, the granular molecular sieve size measurement method, the molecular sieve bulk density measurement method, the molecular sieve crush resistance test method, the abrasion resistance performance of the refrigeration system using molecular sieve desiccants test method"

Industrial activated alumina, the air separation equipment technical conditions of inspection and acceptance with activated alumina

the Performance of zeolite 3a molecular sieve

Yu and zeolite 3a molecular sieve  metallic luster, hardness of 3~5, relative density is 2~2.8, colored with natural zeolite, synthetic zeolite is white, insoluble in water, thermal stability and resistance to acid increasing with the improved SiO2/Al2O3 ratio.mole sieve dehydration have very large surface areas, 300~1000m2/g, Crystal surface in highly polarized, is a kind of high efficiency adsorbent, also a solid, the surface has a high acid concentration and intensity, can cause the carbenium ion-catalyzed reactions.When the composition of the metal ion exchange with other ions in solution, you can adjust the aperture, change its adsorption and catalytic properties, which produce different molecular sieve catalysts.

the Type of Synthesis of zeolite and natural zeolite molecular sieve

Synthesis of zeolite and molecular sieve zeolite in two ways.① the most natural zeolite by volcanic Tuff and tuffaceous sedimentary rocks in marine or lacustrine environment reacts to form.Have been found to have more than 1000 kinds of zeolite minerals, more important has 35 species, common clinoptilolite, mordenite zeolite, Mao Feishi and diamond, etc.Mainly in the United States, Japan, France and other countries, China has a number of mordenite and clinoptilolite zeolite deposit, Japan is the biggest national exploitation of natural zeolite.② resource constraints and by natural zeolite, in the 1950 of the 20th century, the extensive use of zeolite synthesis (see table).

Commodities commonly used prefixes digital crystal structure different mole sieve dehydration  re classified, such as 3A, 4 a, 5 a molecular sieves.In table 4 type a is a class aperture 4Å.Recorded as a molecular sieve containing Na+ Na-A if Na+ K+ replacement, Aperture is approximately 3Å, Which is 3 a molecular sieve;1/3 Na+ over Na-A Ca2+ replacement, Aperture is approximately 5Å, Which is 5 a molecular sieves.

the definition of Molecular sieve

Magnitude, it only allows a diameter smaller than the diameter of the molecules into, so molecular sieve zeolite in the mixture can be screened by size.It is called molecular sieve.Back more than 200 years ago, b.Kelongshitaite first named aluminosilicate zeolites, chemistry formula for m and n are metal ions and Valence;Number of molecule x is silicon dioxide;Y is the number of water molecules;P is the atomic number of aluminum;Q is the number of silicon atoms.molecular sieve dehydration process in the chemical industry as a solid adsorbent material desorption of adsorbed by the molecular sieve can be recycled after use.Also used for gas and liquid drying, purification, separation and recycling.Starting in the 1960 of the 20th century, used as a catalyst in the petroleum refining industry, has now developed a variety suitable for different molecular sieve catalysts for catalytic processes.

Generation of molecular sieve crystals

zeolite 3a molecular sieve for ethanol drying is a very complex process, and know it has not very clear conclusion. However, whether liquid or solid phase change mechanism, the entire crystallization process generally includes the following four steps: 1. aging, multi-silicate and aluminate and then polymerized, or re-polymeric phosphate and aluminate, i.e., the initial formation of a gel; 2. nucleation, molecular structure directing agent in the core or a certain organization TO4 tetrahedral basic structural unit, around which is formed during the formation of nuclei; 3 nuclei growth; 4. crystal growth and cause secondary nucleation. Therefore, the zeolite synthesis process control is mainly reflected in the choice of the regulation of the initial gel formulation and crystallization conditions on. Aging conducive to the formation of nuclei. Higher initial supersaturation favor crystal nucleation and growth, and a single crystal is prepared zeolite synthesis system requires good control over saturation. Increasing the reaction temperature, and promote the transformation of thermodynamics, but also by changing the concentration of the reactants and over-saturation affect the crystallization kinetics.

Structure consisting of ZSM-5 zeolite

ZSM-5 zeolite is a high silica pentasil zeolite, its basic structural unit of the eight five-membered ring composed, called cells, these cells formed by edges parallel to the C axis shared five silicon chain, this basic structural unit by edge-linked into a chain structure, then surrounded the zeolite framework. ZSM-5 zeolite crystal structure of the layer in the C-axis projection. sieve molecular zeolite crystal is composed of many such stacked up. ZSM-5 zeolite supplier main channel window ten-membered ring, a pore size of 0.54nm * 0.56nm.

Zeolite structure unit

There is a three-dimensional molecular sieve between four TO4 tetrahedra sharing vertices formed by connecting the skeleton. T backbone atoms generally refers to Si, Al or P atom, in a few cases refer to other atoms, such as B, Ga, etc. These [SiO4], [AlO4] or [PO4] tetrahedral, etc. constitute the basic skeleton of the molecular sieve adsorber unit, i.e. the primary structural unit. In the 3a zeolite molecular sieve, each T atom is coordinated with four oxygen atoms, each oxygen atom bridging two T atoms, and therefore, the [SiO4] and [AlO4] tetrahedral aluminosilicate molecular sieve xh-5 has formed anion skeleton structure, framework negative charge by the additional cation balance. Aluminosilicate zeolite chemical formula: Ax / n (SiO2) (AlO2) xmH2O (A is a cation of valence n), and adsorbed water located in the pores of the cation.

Carbon molecular sieve works

Carbon molecular sieve nitrogen equipment works: carbon molecular sieve nitrogen equipment (CMS-PSA) is a carbon molecular sieve (Carbon Molecular Sieving, abbreviated CMS) as adsorbent and air as raw material, the use of pressure swing adsorption principle of the separation of oxygen and nitrogen production of high pure nitrogen gas separation apparatus.
zeolite 3a molecular sieve for ethanol drying is based on coal as the main raw material selection, grinding, shaping, drying and activation, heat treatment and other processes from the surface is full and efficient non-polar microporous adsorbent. His ability to adsorb gas molecules of different molecular weights are different, and different kinetic diameter of the gas molecules are adsorbed in the hollow glass desiccant molecular sieve pore diffusion at different speeds.
Carbon molecular sieve oxygen and nitrogen co-adsorption exists, at the same adsorption pressure, oxygen, nitrogen adsorption equilibrium was no significant difference (Figure 3) Therefore, the mere change in pressure is difficult to achieve effective separation of oxygen and nitrogen.
The general nature of oxygen and nitrogen, although the difference is small, but its dynamics are different diameters: 3.5 angstroms oxygen, nitrogen is 3.7 angstroms. Although both small pore size than the carbon molecular sieve, but the rate of diffusion of oxygen molecules hundreds of times faster than nitrogen molecules. This is because the smaller the molecule, the faster its diffusion. 4, in a short time, because the rate of diffusion of oxygen molecules than nitrogen molecules, so the oxygen molecules preferentially occupy the center is a large number of molecular sieve dehydration, adsorption capacity after a few minutes to more than 90%, almost close to balance at a time when the amount of nitrogen adsorption of only about 5%. The use of oxygen, nitrogen adsorption difference within a short time of great features, the program controller at a specific time program between two identical adsorption tower fast switching, combined with pressurized oxygen adsorption and desorption of oxygen pressure swing The adsorption process separating oxygen from air. Oxygen-containing gas is discharged from the bottom of the column, nitrogen adsorption due to little or no adsorption in the gas phase and the product gas is enriched in the form of continuous output.

Why molecular sieve at room temperature does not produce water desorption

ethanol dehydration molecular sieve adsorption of water is adsorbed by the van der Waals force, from the microscopic point of view internal pore molecular sieve to reach static equilibrium, the water molecules are polar molecules break down into hydrogen ions and hydroxide ions. In the adsorption process of water molecules in the double glazing molecular sieve with water decomposition of hydrogen ions and hydroxide ions again to reach static equilibrium, pull off the oxygen-hydrogen releases energy (temperature rise phenomenon). The whole process is the physical reaction. Thus Adsorbent Molecular Sieve Kdhf-03 at room temperature does not produce water desorption.

What is the molecular sieve for insulating glass:

Molecular sieve insulating glass all comply with performance indicators and do not have any impact on their physical and chemical properties, only qualified called double glass desiccant molecular sieve for insulating glass. Meet this requirement only Automobile Desiccation Molecular Sieve.

Features of Molecular sieve absorption

activating molecular sieves capacity is very strong (and therefore is widely used as a desiccant), for gas purification, save should avoid direct exposure to the air.Stored for a long time and have moisture absorption regeneration of zeolite molecular sieves should be carried out before use.Molecular sieve avoiding oil and liquid water.Should be used as far as possible avoid contact with oils and liquid water.Drying in production of industrial gases, air, hydrogen, oxygen, nitrogen, argon and so on.Adsorption dryer with two parallel, a job, while the other can be regenerated.Alternating work and regeneration, to ensure a continuous operation.Dryers at 8-12 work under impact regeneration in a heated to 350 degrees.molecular sieve manufacturers regeneration temperature is slightly different in different specifications.Certain organic molecular sieves for gas-phase has a good catalyst.Also known as zeolites and zeolite, is a crystalline aluminosilicate, structured and uniform pores in its crystal structure, molecular size of aperture for

Molecular sieve

Due to contains electric price lower and ion RADIUS larger of metal ion and combined state of water, water molecular in heating Hou continuous to lost, but Crystal skeleton structure not variable, formed has many size same of empty cavity, double glazing molecular sieve empty cavity and has many diameter same of micro-hole connected, these tiny of cavities diameter size uniform, can put than channel diameter small of molecular adsorption to cavities of internal in the to, and put than channel big of molecular exclusion out, thus can put shape diameter size different of molecular, polar degree different of molecular, boiling point different of molecular, Saturation level separating different zeolite 3a molecular sieve  that is, with "screening" molecular function, it is called molecular sieve.Current molecular sieves in the metallurgical, chemical, electronics, petrochemicals, natural gas is widely used in the industry.

Determination of the true density and apparent molecular sieve catalyst density

Determination of true density, commonly used nitrogen replacement method in a vacuum adsorption capacity device. Atmosphere can enter all the pores of the sample itself is rarely to be adsorbed, without chemical change, is the ideal replacement media. If nitrogen is not readily available, nor require very strict, the organic liquid or water may be used in place of benzene, isopropanol and the like. These alternative molecular substances can only allow them to enter the cross section of a molecule into the pores, but can not enter all the pores of the sample, so had an approximate density side is the matrix density, i.e., apparent density Pa.
Isopropyl drunk fluidized catalyst for dehydration of ethanol replacement method is more commonly used measurement method Pa. This method has been recommended Weld density bottle and a feeding device with a capillary stopper. Pre-test sample with water and isopropyl alcohol in the side of the density of a given temperature correction ju bottles. After the sample is added to the density of the bottle, said the quality of the sample, and then pull the plug capillary tube. The density of the bottle mouth set in the ground on the charging device following grinding mouth tube, evacuated, while adding isopropyl drunk part in a test tube feeding device. When the pressure is less than the sample Ou on "133. 322P. When the rotary piston, so slowly adding isopropanol sample, then put the new capillary density injustice bottle stopper, at a given temperature side after weighing balance. According to these mass and temperature of the water at the side of a given density,
Hue grain density meter is filled with mercury, although the determination of the appropriate, measured before first checking for leaks glass piston. After the first six piston pump is turned on, open the piston 4 is evacuated for some time, with 7 mercury pressure gauge to check the connection of the piston vacuum. Once confirmed the formation of a vacuum, and then close the piston 4 and 7. 6 rotary piston slowly into the atmosphere after the pump stops. Slowly open space filled with mercury piston 3 2, closed when the mercury rose to the surface of the piston 4 position 3, this time on the left to read the calibration tube demand side of the piston Liu, set V1 (MI.), And then put through the piston 4 into the atmosphere. Open the piston 3, so that the mercury level drops. When the lid 5 open mill, into the weighed sample grain sheet, as before re-operation. Read volume V3 (mL), mercury surface down to the proper position, the piston 3 to close and open the cover 5 day wear, Samples were taken with a teaspoon.

Factors affecting the molecular sieve catalyst Hang crushing strength

Jing and zeolite catalytic factors affect the mechanical strength of the lot. Their chemical composition determines the aggregate or cohesion within the crystal, i.e. tensile strength. It is the inherent strength of the product. Usually there is a rough relationship between the inorganic solids usually strength and hardness to their melting point. A low melting point with the body has a low strength and hardness, and high melting point by its high hardness and strength.
First, the product prepared by a different mountain. Surface contact points produce a different space structure, defects and grain powder room, etc. whip, which naturally also affect its mechanical strength.
Second. The mechanical strength of the product will occur in use changes, such as the reaction was adsorbed on the solid surface. Generally reduces its mechanical strength, which is - during the reaction to promote the catalytic cracking Xia Jing and ethanol dehydration molecular sieve to Factors. Further use of the time and temperature will affect its mechanical strength.
Hang crushing strength in the industry and the size of the zeolite catalytic Jing direct impact on their effectiveness in working conditions and life. If Hang crush strength is too small. It may break or powdering during use, which not only shortens the molecular cry, catalyst life. But also lead to uneven distribution of sulfur donors, blocking game system to increase bed resistance, Estrogen can cause severe security risk and even forced to stop.

molecular sieve ethanol dehydration

Zeolite catalyst density analysis

(1) Bulk density Bulk
Test Method This bulk density is in a container, by free-fall section exposed to the air for 24h the bulk density of the sample.
This method takes the instrument may be a simple cylinder for a tap or bulk density of the analyzer.
(2) tapped bulk density
Determination of tapped bulk density of conventional vibration method, using the experimental apparatus shown in ASTM standard specified in FIG. 3-7, the test method is the pretreatment of the catalyst at 400 ℃ 3h in air (reduction catalyst should be in an inert atmosphere be). After cooling, the operation of the vibrator in the measuring device to the second 2 ^ -3m1. rate added through the feed hopper into the measuring cylinder, and then continue the vibration lmin, shutting down the vibrator, amount of catalyst volume and weighed mass, calculated tap bulk density.
Calculated with the formula without standard equipment in the laboratory, can be used in the rubber board 250mL graduated cylinder side edge joined to make a real sample, to be added to complete the sample continues to trample real 2min. This method measured the non-strict measure bulk density.

Anti-crush strength of the catalyst and molecular sieve methods

Because of different shape and molecular sieve drying, different stress points, said the crush strength of the ways are different. Usually divided into axial (or normal phase) Crushing strength (N / cm2), radial (or lateral phase) Crushing strength (N / cm) and the point Crushing strength (N /%). Where the former surface contact. The latter two are in line contact and point contact, respectively mouth (axis) ,. (Diameter) and. (Dot) said. Strip, ring, shaped spokes reminder
Agents and molecular sieve xh-7 with radial crush strength is represented by dots and spherical crush strength is expressed.
Catalytic Jing large particle size or carrier, such as Raschig rings, a spherical molecular sieve, the board side of the test method can be used to mean value. Small particle size catalyst, is preferably used stacking strength meter, deep extent stacked on top of a volume of the sample under pressure chipping 'as the catalyst for the fine particles, the average number of single V Hang crush strength of the catalyst is not important. Sometimes probably a few percent of the crushing pressure will cause a surge in the catalyst bed was forced to stop.

Jing zeolite catalysis and adsorption properties of packaging materials and moisture

Jing and zeolite catalysis is a porous material. Some types of finely powdered products or very fine. Therefore they have a large surface area thereof. The internal surface of the atom atom in a different state, the internal atomic attraction uniformly distributed in the circumferential country atom force field to make the saturation equilibrium, while the surface atoms of this force field is not saturated, That surface adsorption force field exists, there is the surface energy. When the gas or liquid molecules into the force field range, it will be adsorbed, thereby reducing the surface energy by the white system. This unsaturated force field scope. Roughly equivalent to the size of the molecular diameter. That is about a few angstroms. Therefore, they have a very clear its adsorption performance is good adsorption Jing.
Depending on the size of adsorption. Adsorption phenomena generally classified into two types of physical adsorption and chemisorption. Physical adsorption force is van der Waals forces. Therefore, similar to the adsorption heat and condensation heat, and the adsorption is reversible adsorption is fast, a greater speed at low temperatures. Chemisorption between the adsorption and chemisorption Jing success key role. Adsorption heat large (> 10kcal / mol, lea [. A 1840J). And the chemical reaction heat is similar but different chemical adsorption and chemical reaction. No new material is generated. Chemical adsorption is irreversible, and must have a high activation force dish surface can be overcome.
Which adsorb moisture in the air is the most common physical adsorption phenomenon. Such as zeolites have play very absorbent sheets can, even at very low partial pressure or concentration. There is still a very high adsorption capacity bi, so no matter what is used. Can get a good depth of dry operation. Or zeolite 3a molecular sieve for ethanol drying catalyst during the activation. Can not completely remove the moisture contained therein, but also more or less finished product prior to packaging certain adsorbed moisture, the moisture of the total sub-Jing or Automobile Desiccation Molecular Sieve catalyst and a percentage of this substance is said to Lang moisture for most packaged goods, usually expressed as a mass fraction II.