Silica Gel

Silica Gel is used to control the relative humidity level in the surrounding environment. Silica Gel acts as a harmless conventional desiccant commonly used to adsorb 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 adsorb 40% of its weight and rapidly bring down the relative humidity (RH) by up to 40% 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 300ºF (150ºC) to remove the moisture and reuse the substance. 

Silica Gel is available in 3 common types: white, orange, and blue. 

White Indicating Silica Gel

White Silica Gel (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 monitor 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 Silica Gel is 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. 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, making it ideal for a wide array of applications. 

To learn more about our moisture solutions, please visit our blog on desiccant bags. Direct purchase is also available from our online store. For bulk quantities, custom sizes, or special printing requirements, feel free to contact us.

White Non-Indicating Silica Gel
  • Tasteless
  • Odourless
  • Food-safe
  • FDA compliant
  • Non-toxic
  • Non-corrosive 
  • Non-reactive (does not change colour when exposed to moisture) but appears hazy or milky when saturated 
  • Silica gel can adsorb up to 40% of its weight in water
Blue-Indicating Silica Gel ​
  • Odourless 
  • Non-corrosive
  • Changes from blue to pink when saturated
  • Non-dusting packing in Tyvek desiccant bags available 
  • Works well for non-dusting packing for electronic equipment
  • Silica gel can adsorb up to 40% of its weight in water
 Orange-Indicating Silica Gel
  • Odourless
  • Heavy metal-free
  • Non-corrosive 
  • Environmentally friendly 
  • Changes from orange to green when saturated
  • Silica gel can adsorb up to 40% of its weight in water
  • White Indicating Silica Gel
  • Blue Indicating Silica Gel
  • Orange Indicating Silica Gel

Silica Gel Product Brochure: Download