Five common desiccants: 1 and quicklime desiccants: quicklime desiccants are alkaline desiccants, which are white calcium oxide solid particles made from natural calcium carbonate ore by high-temperature calcination. It does not contain harmful substances and heavy metals restricted by European and American countries, and it is a desiccant hygroscopic material that meets the requirements of environmental protection. However, it is worth noting that alkaline desiccants such as quicklime desiccant cannot dry acid gases (such as hydrogen chloride and hydrogen sulfide).
2. Montmorillonite desiccant: Montmorillonite desiccant, also known as clay desiccant, is made of natural montmorillonite ore after mining, high-temperature heating, organic matter carbonization, expansion of montmorillonite ore body, steam treatment, drying, activation, crushing and screening. The appearance is a small gray ball, which is most suitable for moisture absorption in the environment below 50℃. The advantages are: natural, non-toxic, pollution-free and degradable; And the price is cheaper. The disadvantage is that it is not resistant to high temperature. When the temperature is higher than 50℃, the degree of "water release" of montmorillonite is greater than that of "water absorption".
3. Active mineral desiccant: The active mineral desiccant is refined from pure natural raw minerals and active moisture absorbent, and its appearance is gray-white pellets. The moisture absorption rate is above 50%, and it is a nontoxic, harmless and degradable environment-friendly desiccant. The product has good adsorption performance at room temperature and general humidity, and has the effects of adsorption activity, static dehumidification and odor removal.
4. Silica gel desiccant: Silica gel desiccant is an acidic desiccant, and its main component is silica. It is a highly active adsorption material and does not react chemically. It is made of natural minerals through purification and processing into granules or beads. The inside of this crystal is a very fine pore network structure, which can absorb water and retain it through its physical attraction.
5. molecular sieve desiccant: It is a synthetic desiccant product with strong adsorption to water molecules. It is a crystalline aluminosilicate compound. Its crystal structure has regular and uniform pores, and its pore size is of the order of magnitude of molecular size. It only allows molecules with smaller diameters to enter, so it can screen the molecules in the mixture according to their size, so it is called molecular sieve. Its pore size can be controlled by different processing technologies, and it can adsorb other gases besides water vapor. At the high temperature above 230℃, it can still contain water molecules well.