Desiccant Cartridges
Cleatech Desiccator Cabinets could be used by any type of desiccant. Most ideal desiccants are listed below:
DRI_BOX Desiccant Cartridges Ideal for Cleatech desiccator cabinets. Color turns to pink from blue when it can no longer absorb more moisture. It can be re-generated in either a conventional oven or a microwave oven. 2″x2″x1″ transparent polycarbonate container holds desiccant crystals. Each desiccant cartridge contains 45.5 gms of indicating Silica gel. It’s available in packs of four in a sealed bag.
Bulk indicating desiccant, Blue Silica gel available in cans of 5 lb. 2-4 mm bead diameter. Indicating silica gel has been impregnated with cobalt chloride which turns from blue to pink when it has reached its limit of adsorption capacity.
Scienceware or VWR Reusable/Disposable Desiccant Cartridges Ideal for S-1400 Cleatech desiccator cabinets. Color change tells you desiccant is working. To regenerate, simply heat in a 122°F (50°C) oven overnight.Clear polystyrene dish with porous membrane cover holds desiccant crystals. Silica gel crystals are inert, noncorrosive and nontoxic.
Scienceware or Fisherbrand Reusable Desiccant Canister Ideal for S-1400 Cleatech desiccator cabinets. Perforated aluminum canister with silica gel drying agent absorbs 6% moisture by weight, maintains a dry atmosphere in 3 cu. ft. (0.09m3) of space. Blue gel turns pink when saturated; heat at 150°C (302°F) for 3 hours to regenerate
Desiccant Types
Desiccant is a substance that absorbs water. It is most commonly used to remove humidity that would normally degrade or even destroy products sensitive to moisture.
The desiccant used in a desiccator normally made of the following desiccant materials. They are Silica Gel, Indicating Silica Gel, Molecular Sieve (Synthetic Zeolite), Montmorillonite Clay, Calcium Sulfate and Calcium Oxide. Each material has its own advantages and disadvantages when using them as the desiccant.
Silica gel is silicon dioxide (SiO2) appears in either granular or beaded form. The silica gel will pull in moisture at temperatures up to 220°F (105°C). but once the temperature goes up more than 100 degrees F, the silica gel will work at the lower absorbing rate. It commonly found in the food and pharmaceutical industries and this is the only desiccant types which FDA approved for the usage direct contact with food and pharmacy items.
Indicating silica gel is a silica gel has been washed with a concentration of cobalt chloride. The cobalt chloride is a deep blue color when it is dry and turns from blue to purple to pink as it becomes saturated with moisture. Typically, the color changes indicate it is time to replace the desiccant.
Molecular sieves (also known as Synthetic Zeolite) adsorb moisture more strongly than either silica gel or clay. Zeolites are minute crystalline solids that have a distinct structure. They generally comprise of oxygen, silicon, and aluminum in their scaffold, and water, cations, and other molecules in their pores. The molecular sieve desiccant can hold up moisture under 450 degrees F temperature. But It doesn’t have FDA approval for food and pharmacy items.
Calcium oxide and Calcium Sulfate (also known as Drierite) are made of lime and gypsum. Both are the crystal based with Calcium which is more stable chemically, non-toxic and non-corrosive. Normally they are sold in package form. Calcium oxide moisture adsorptive capacity of not less than 28.5% by weight. It is most effective where a low critical relative humidity is necessary, and where there is a high concentration of water vapor present. In calcium sulfate, its low cost must be weighed against its equally low adsorptive capacity. It adsorbs only up to 10% of its weight in water vapor.
Montmorillonite clay is a naturally occurring adsorbent created by the controlled drying of magnesium aluminum silicate of the sub-bentonite type. Clay is a good basic desiccant that works satisfactorily below 120°F. Above 120° F, the clay might give up moisture rather than pulling it in. Montmorillonite clay is widely used in medicine and pharmacology and it ‘s usually least expensive desiccant per pound.
