Messi Biology Co., Ltd. states that magnesium oxide (MgO), due to its unique physical and chemical properties, is widely used as a highly efficient desiccant in industrial and packaging fields. Its moisture absorption mechanism differs from traditional physical adsorption desiccants; it belongs to chemical moisture absorption reactions, thus possessing stronger moisture absorption capacity and a more lasting drying effect.
1. Principle of Moisture Absorption Reaction
When magnesium oxide absorbs water, the following reaction occurs:
MgO + H₂O → Mg(OH)₂
This reaction is an endothermic chemical reaction. The magnesium hydroxide produced after the reaction is stable and non-volatile, ensuring that the desiccant will not “re-wet” or liquefy after absorbing moisture, making it suitable for applications with strict environmental requirements.
2. Structural Characteristics Aid Moisture Absorption Performance
- Magnesium oxide is a porous material with a large specific surface area.
- Its crystal structure contains a large number of active sites, especially unsaturated oxygen ions, which readily form hydrogen bonds with water molecules.
- These structural features enable it to rapidly capture and solidify water molecules from the air.
3. Advantages of Chemical Moisture Absorption
- Strong moisture absorption capacity in high humidity environments: Unlike desiccants that easily saturate in high humidity due to physical adsorption, MgO can continuously absorb water even under high humidity.
- Non-corrosive with no liquefaction risk: The magnesium hydroxide formed after moisture absorption is solid, with no risk of leakage.
- Good thermal stability: It can maintain structural stability even in high-temperature environments without degradation or failure.
4. Strong Environmental Adaptability
- Applicable in various fields: Such as electronic components, pharmaceutical packaging, instruments, etc.
- Does not rely on extremely tight packaging environments, making it suitable for placement in complex transportation or storage conditions.
Here’s an image illustrating the chemical reaction involved: