Desiccants can be used to protect many things that need to be kept dry and protected from the damaged caused by moisture being attracted to the items.
The item that needs to be protected is placed inside of an air-tight container or something that can be tightly closed to prevent moisture from getting in, the desiccants is then placed inside the container with the item. It will rapidly desiccate the air inside the container and protect the items from being damaged by any moisture in the air inside.
There are several different types of desiccants which can be used. Depending on what kind of item needs to be preserved and how it is placed in the container. Continue reading →
Various substances are used as desiccants, each with different properties and limitations. All desiccant types accomplish their jobs by a process known as adsorption, in which moisture forms a film on the substance’s surface, but does not permeate it.
Montmorillonite Clay is a naturally-occurring form of magnesium aluminum silicate that is capable of adsorbing large amounts of moisture, and can be used repeatedly without deterioration. It is usually the cheapest desiccant type available.
Clay only performs well at temperatures below 50 C. At higher temperatures, it tends to give up moisture instead of adsorbing it. In applications where the desiccant must be used or stored at high temperatures, it is necessary to use some other desiccant.
Silica gel is the only desiccant type that is approved by the FDA for use with products to be consumed internally, so it is generally used in packaging for food and pharmaceutical products. It will perform well up to about 105 C. As temperature rises, the adsorption rate slows but remains high enough to be effective. The ideal environment for silica gel performance is about 70 to 90 degrees F and about 60% to 90% humidity.
Both silica gel and clay have variable pore sizes, and can be used to adsorb substances other than water. Continue reading →
Reusable desiccants are hygroscopic substances that absorb water and sustain or induce a dry state in its close surrounding area. The variety that is pre-packaged is typically solid, but they also come in other states as well. Some are meant for specialized purposes like chemically bonding water molecules, and this is an instance when they would not be in a solid state.
Some reusable desiccants are used to remove excess humidity. The primary function of doing so is to preserve products that are sensitive to moisture in the air that may otherwise become damaged. Insulated windows are also desiccants. When this type of window is put into the space that is between the edge of the window and the air space, the accumulation of moisture and condensation between the window panes is prevented.
Salt is also a desiccant. It is used to preserve foods by drying them and is also used in mummification. Rice is also a desiccant but is not as effective as salt. Rice is sometimes used in salt-shakers to make shaking and pouring more effective. It is only an effective reusable desiccant if it is surrounded by an environment that is organism-hostile; it is mainly considered an optional alternative. Continue reading →
Desiccants are substances which draw in moisture from their surrounding environment. Some also desorb moisture into the atmosphere. They are eco friendly and help in protecting the environment. They prepare chemicals in chemical plants, protect moisture sensitive items, protect against corrosion, etc.
Desiccants provide excellent corrosion protection for dehydration applications such as natural gas storage, air dehydration, gas pipeline heaters, etc. Some common desiccants are activated carbon, sodium perchlorate, calcium sulfate, silica gel, salt, and rice. Salt is used to preserve dead bodies especially in hospitals for exhibition and also in Egypt to preserve mummies, which prevents the decay. Rice is used to maintain granularity of salt and prevent the moisture from sticking to the edges of the salt shakers.
They also serve as evaporation means say for example, many objects are allowed to evaporate and if their moisture content matches with the enviornment conditions then it is difficult to allow them to evaporate water on their own, hence desiccants can take care of this job effectively without affecting the environment. They can be used for variety of applications since some desiccants are anti fungal, anti microbial, or anti viral.
Moist metal surfaces are very much prone to corrosion. Desiccants absorb all the moisture on the metals and prevent them from corrosion and hence are very much environment friendly. Continue reading →
