Silica gel desiccant is a kind of absorbent with strong adsorption capacity, fully exposed to the air (relative humidity 80%-90%), temperature 25%) can reach more than 30% water absorption rate within 48 hours. Silica gel desiccant is a kind of substance formed by artificial chemical reaction of sodium sulfate - silicon dioxide. This synthetic chemical substance has a porous internal structure and an irregular granular external structure. The formation of numerous capillary voids between the internal molecules can form the so-called capillary absorption and condensation effect, which can effectively absorb the surrounding water, alcohol, hydrocarbon and other chemical molecules. People make use of these physical properties of silica gel to make silica gel desiccant become the best absorbent today