Silica Gel is used to control relative humidity level in surrounding environment.
Silica gel acts as a harmless conventional desiccant commonly used to absorb moisture and water vapour in medication bottles, foods, and leather products. Effectively absorbing moisture and humidity reduces the likelihood of mould growth and can prevent food spoilage. Packets of silica gel used in electronics reduce harmful and damaging condensation.
Made from silicon dioxide (SiO2), silica gel is the same material found in the makeup of quartz. It is composed of one silicon atom combined with two oxygen atoms. Silica gel is created by processing sodium silicate with an acid patented in 1919 by a John Hopkins University chemistry professor named Walter Patrick. When the substance undergoes drying, it forms a xerogel that successfully acts as a desiccant.
Silica gel is like porous sand. It boasts tiny pores that can rapidly absorb and hold moisture. The non-reactive and odourless gel can absorb 40 per cent of its weight and rapidly bring down the relative humidity (RH) by up to 40 per cent in an enclosed space such as a sealed container. Water molecules quickly stick to the surface of each gel granule. The interconnected pores on the gel granule use the process of capillary condensation to remain dry even when fully saturated with moisture. After saturation, heat the silica gel to 300 degrees Fahrenheit (150 C.) to remove the moisture and reuse the substance.
Types of Silica Gel
Common types of silica gel include white, orange, and blue.
- White Indicating Silica Gel: White (it often appears clear) is a non-indicating silica gel that is completely odourless, tasteless, non-corrosive, non-toxic, and non-reactive to chemicals. White silica gel makes a food-safe, moisture preventative and is common in food packaging. Commonly used with a humidity indicator card to mointor the replacement requirements of the desiccant.
- Blue Indicating Silica Gel: Blue silica gel contains cobalt chloride, which appears blue until exposed to moisture. Upon saturation, it turns pink to alert when desiccant occurs visually. Stream Peak’s Humi Dri Blue typically packed in Tyvek desiccant bags for immediate use in sensitive electronic equipment.
- Orange Indicating Silica Gel: Often called Environmental gel (Envirogel), orange silica gel contains a safe organic indicator known as methyl-violet, which transitions from orange to green after saturation with water vapour occurs. Orange indicating silica gel makes an acceptable alternative to blue indicating silica gel. It is heavy-metal free, non-corrosive, non-toxic, and environmentally friendly, which makes it ideal for a wide array of applications.
Silica gel can absorb up to 40 per cent of its weight in water
White Non-indicating Silica Gel
Blue-indicating Silica Gel
Orange-indicating Silica Gel
|Silica gel Brochure||View|
Tags: blue silica gel, white silica gel, orange silica gel, silica gel, silica gel desiccant, desiccant, humi dri, Silica Gels, Silica, Sillica Gel, Relative Humidity Absorber, Relative Humidity, Moisture Adsorber, Water Vapor Adsorber, Odorless Adsorber, non-indicating silica gel, silica gel sachet, organic moisture adsorber,