White A Grade Silica Gel Cas No: 7631-86-9

Silica gel is an amorphous form of silicon dioxide, which is synthetically produced in the form of hard irregular granules (having the appearance of crystals) or hard regular beads. A micro porous structure of interlocking cavities gives a very high surface area (800 square meters per gram). It is this structure that makes silica gel a high capacity desiccant. Water molecules adhere to the Silica Gels surface because it exhibits a lower vapour pressure than the surrounding air. When equilibrium of equal pressure is reached, no more adsorption occurs. Thus the higher the humidity of the surrounding air, the greater the amount of water that is adsorbed before equilibrium is reached. It is in these higher humidity conditions (above 50% Relative Humidity) that stored or in-transit items are susceptible to damage. The beauty of silica gel is the physical adsorption of water vapour into its internal pores. There is no chemical reaction, no by products or side effects. Even when saturated with water vapour, silica gel still has the appearance of a dry product, its shape unchanged. Silica Gel is one of the oldest and most popular desiccant and adsorbent used for a wide number of industrial and consumer applications.