Desiccator

Desiccant is a type of chemical used in a closed chamber or known as desiccator to absorb moisture inside the chamber in order to achieve the dry condition in-situ. There are many types of desiccant being used, but the most common one is the silica gel. You will find most of them in a small sachet of any new electrical equipment packaging.

The original color of silica gel is transparent, they are in granular form which will gradually change to hazy or milky color when it absorbs moisture. The changes of the coloring of this substance is due to the chemical reaction between the silica gel and water being absorbed. It is also this changes that make it difficult to detect how much level of moisture being absorbed as well as the water content in the silica gel itself.

To make thing easier, there is a company has developed a new type of silica gel products which originally being orange or blue color, but the color changes as they absorb water. This has help people to identify the moisture detection by the changes of color and remind them to change the desiccant before the chemical lose its absorbility.

This colored silica gel can be produced in either granular or bead form, actually they are produced synthetically with many interlocking cavities which gives a high area of exposure. With the existence of cavities and the granular form, it provides greater surface area per cubical which means better absorption level. The cavities functions as the loop holes to capture the smaller water molecules by attracting the moisture to the gel closer.

The orange colored silica gel is infused by a non-toxic organic indicator which absorbs water to change into dark green color; the blue colored silica gel is produced with cobalt chloride that turns to clear as it absorbs water. It is like a magical show where the process of changing color is reversible where the silica gel will return to its original color as the trapped moisture evaporates. Instead of observing the changes of color to indicate the absorption of moisture, the reversible of color changes also indicating the readiness of the gel to be reused.