1. what are VOCs?

VOC's the English name of volatile organic compounds"Volatile Organic CompoundsThe abbreviation is sometimes called VOC.

VOCs can be further classified into eight class based on their chemical structure:: alkanes, aromatic hydrocarbons, olefins, halogenated hydrocarbons, esters, aldehydes, ketones and other compounds.VOCsThe sources can be divided into industrial sources, mobile sources, living sources, etc., of which industrial sources are the main source of emissions, accounting55%.

VOC in the common sense refers to volatile organic compounds (VOCs), which are defined by the World Health Organization as compounds with a boiling point of 50°C-250°C at room temperature; however, the definition in the environmental sense refers to the active type of VOC, i.e., the type of VOC that causes harm. Common VOCs include benzene, toluene, xylene, styrene, trichloroethylene, trichloromethane, trichloroethane, diisocyanate and diisocyanurate.

In daily life, vinegar contains acetic acid (acetic acid), and alcoholic beverages contain alcohol (ethanol), which can be volatilized into the air and are VOCs. perfumes contain a variety of aromatic compounds and essential oils extracted from plants or chemically synthesized, and many of them are VOCs, such as aromatic aldehydes, aromatic esters, etc. In addition, cosolvents in perfumes are usually ethanol. In addition, the co-solvents in perfumes are usually ethanol and so on. Some fruits (e.g. lemons, oranges, etc.) and everyday cleaners contain limonene, which is also an aromatic VOC. Indoor air pollutants such as formaldehyde, benzene, toluene, etc. are released from home décor and furniture.

2.Principle and advantages of zeolite molecular sieve adsorption of VOCs

There are various treatment methods for VOCs, among which the adsorption method is easy to operate, economical and reasonable, and is one of the effective methods for enriching and separating VOCs. In recent years, zeolite rotor, zeolite honeycomb, zeolite rotor combined with regenerative thermal oxidation (RTO) or catalytic combustion (RCO) VOCs treatment technology has been attracting more and more attention.

Molecular sieve (zeolite) is an inorganic crystalline material composed of tetrahedra (TO4 (T=Si,Al,Petc.)) with regular pore structure formed by common vertex connections. Adsorption of VOCs by molecular sieves is mainly carried out through its porous material characteristics, and various low concentrations of VOCs can be removed by adsorption. The adsorption of VOCs by molecular sieves includes physical adsorption and chemical adsorption, in which the physical adsorption is mainly related to the pore size distribution of molecular sieves and the diameter of VOCs molecules, while the chemical adsorption is mainly related to the silica-aluminum ratio, the type of cation and the dipole moment of VOCs molecules. Numerous studies have shown that topology, cation type, multistage channel and hydrophilic hydrophobicity are the key factors affecting the adsorption of VOCs on molecular sieves.

Molecular sieve adsorption technology for VOCs removal has been widely used in a variety of working conditions due to its good selectivity, high safety, high removal efficiency and environmental friendliness. Molecular sieve is also the most commonly used carrier material in catalysts with good thermal stability and high adsorption capacity. Molecular sieve is the core material of zeolite wheel, honeycomb and rotor, usually with uniform pore structure and large specific surface area, which has a broad application prospect in the field of gas adsorption and separation. Different types of molecular sieves have different structural characteristics and their application areas are quite different. Among them, high silica molecular sieves are ideal adsorbents for adsorption of VOCs because of their good hydrophobicity and high stability.

3. How to Select Zeolite Honeycomb, Zeolite Rotary Wheel and Zeolite Rotary Cylinder

Whether it is a zeolite honeycomb, a rotating wheel or a rotating cylinder, it is necessary for the selective adsorption of VOCs and its high capacity, but there is still a big difference between the three.

1. The zeolite honeycomb is made into a monolithic honeycomb by a special preparation process, which can reduce the wind resistance, and the adsorption efficiency of organic matter is greater than 90%, which can be used for a long time for adsorption-desorption cycle. Therefore, the selected molecular sieve needs to be easy to shape, especially in the extrusion, to ensure the consistency of the body. By adding cellulose, glycerin, etc., the synchronous and uniform drying of the shaped body is realized.

2. The zeolite runner is a kind of rotary adsorption equipment prepared by coating zeolite molecular sieve on honeycomb porous glass fiber. Therefore, the selected molecular sieve should be suitable for the slurry coating process. The molecular sieve used in the runner requires fine particle size, easy dispersion and no sedimentation.

3. The core component of the zeolite drum is the honeycomb module, which is generally larger in size. The molecular sieve used in the rotating cylinder should have the characteristics of light density and good fluidity. The modules produced can have low energy consumption and high yield.

In addition, in some scenarios, the VOCs component contains part of the olefin component, then to choose the anti-polymerization molecular sieve. Because olefin components are prone to dehydration condensation at high temperatures and become esters. This kind of material is not easy to desorb, the final carbonization, blocking the molecular sieve pore, resulting in molecular sieve failure.

4.The advantages of porcelain molecular sieve

1, the category is complete. China porcelain in the field of VOCs adsorption accumulated many years of experience, molecular sieve category can be applied to most applications. For the runner, drum, extrusion honeycomb, formed a variety of special molecular sieve.

2, customized: the company has VOCs adsorption evaluation laboratory, with molecular sieve development advantages, according to the different needs of customers, the development of a more suitable molecular sieve.

VOCs adsorption molecular sieve