What is Silica gel?

What Is silica gel

What is Silica gel? Commonly used in the healthcare and electronics industry and packed a small white or transparent packaging, the moisture absorber is an amorphous form of silicon dioxide with atoms of an irregular framework. The absorbers contain nanometer voids spaces and a tridimensional structure of oxygen and silicon atoms. The liquid or gas material that fills the void or pores are called silica gel xerogel. 

Silica gel usually shaped and manufactured into a granular form. Chemicals added to form indicating absorbers which allow a change colour after its saturated. 

What are the properties of Silica Gel?

The desiccants absorb moisture due to its high surface area of around 800 m2/g. This physical property of the desiccant makes it ideal as a drying agent which used to protect various goods and products against corrosion, contamination, spoilage and growth of mould.

Available in loose bulk or packets for different degree of humidity detection and control purposes, silica gel differentiated into three different colours, white, blue and orange. 

Difference Between White, Orange, and Blue Silica Gel

White Silica Gel

A non-indicating moisture absorber, like its name, suggests, does not change in colour even after saturation. A method to identify its saturated limit would be to measure the absorber by its weight or using together with a humidity indicator card.

Orange Silica Gel

Also known as Envirogel, the desiccants has an element for indication called methyl violet, that is capable of changing colour from orange to green/ colourless once saturated with moisture. Although it has some medicinal merits, it is not safe for consumption.

Blue Silica Gel

This moisture absorber, on the other hand, incorporates cobalt chloride, allowing it to change its colour from blue to pink once it is saturated fully with moisture. Cobalt chloride is toxic and not recommended to use with food products. 

Applications of Silica Gel

The presence of moisture may encourage the growth of mould and decreases shelf life in food packaging, highly sensitive goods such as electronics easily damaged by condensation.  

Silica gel used as a drying agent in packaging has several benefits. When filled in desiccators, the desiccant will dry the air in industrial compressed air systems. The absorber will remove moisture from the air intake before entering the sealed container. They are commonly used as a preservative to control relative humidity in places like libraries and museums. Other applications include cameras and fish oil packaging. 

Find out more about our desiccant bags from our video