Lab Desiccants and Drying Agents
Hygroscopic substances and drying agents for use in laboratory settings; drying agents are commonly used to keep other substances and samples dry, or to prevent moisture from forming on/in containers. Products include drying tubes, kits, etc.
Desiccants are typically chemicals or compounds that are hydroscopic (readily absorb moisture). Common desiccants include clays, silica gels, and calcium sulfate.
In the lab, desiccants are commonly used in desiccators and desiccator cabinets, with in-line air and gas drying columns, in absorption bulbs, U-tubes, glove boxes, sealed chambers, and wherever a dry environment is required. They are also used during transport, for storage, and maintaining materials and products ─ everything from clothing to electronics.
The moisture may come from a variety of sources:
- Water vapor in the air
- Moisture in packaging materials
- Moisture from permeation or leakage
Some desiccants contain an indicator or additive that produces a color change with moisture absorption. The indicator allows the user to see when the desiccant has absorbed its maximum amount of moisture and needs to be replaced or regenerated.
Some desiccants can be reused many times simply by heating them in an oven to allow moisture to evaporate. For indicating desiccants, one can also easily tell when the desiccant is again ready to use by the change back to the original color.
Desiccants may be available in a range of mesh or particle sizes. The Tyler Equivalent is a common type of mesh sizing and indicates the number of openings per linear inch of mesh. Common desiccant mesh sizes are 4, 8, and 10 to 12. Size 4 is typically used in gas phase applications; they are larger and less likely to break. Size 8 is smaller and can be more tightly packed.
DELTA ADSORBENTS Blue Indicating Silica Gel Granular 6-16 Mesh | 5lbs
Blue Indicating Silica Gel Granular 6-16 Mesh is the naturally occurring mineral silicon dioxide that has been purified and processed into a hard, smooth beaded form. The beads are then saturated with a moisture indicating solution that gives them a deep blue color when dry. It is also known as a narrow pore silica gel and has a vast network of interconnecting pores with diameters of 20-30Å. These pores have a strong affinity for moisture and use physical adsorption and capillary condensation to trap and hold it. Silica gel will remove moisture at temperatures as high as 220°F, but is best used at room temperature (70-90°F) and high relative humidity (60-90%Rh). The color changes from blue to purple to pink as it adsorbs moisture.
Forcoven Products Inc 50 BAGS/CS ATTAPULGUS 150G/BAG
Attapulgus Clay, 50/Bags, Each Bag Is 150 Grams (100 On The Bottom And 50 On The Top)
Cole-Parmer Humidity Sponge, Regenerable; 3" X 3" bags, 40 bags/pk
Humidity sponges meet all drying requirements. One bag will retain 16% moisture in a container with a volume of two gallons (476 cu. in.) The sponges are non-toxic and are Class M3.5 cleanroom-compatible.
Sigma Aldrich Fine Chemicals Biosciences Phosphorus pentoxide | 1314-56-3 | MFCD00011440 | 100 g
Phosphorus pentoxide | Mol Wt: 141.94 | 1314-56-3 | MFCD00011440 | 100 g
Cole-Parmer Drierite Drying Tube, 300 mL/min, 4/pk
Drierite Drying Tubes measure 8"L x " OD and come filled with 30 grams of indicating Drierite. Tubes dry to a dew point of 100degF with a flow rate up to 300 mL/min. Acrylic construction with polypropylene end caps. Inlet/outlet ports accept " to 3/8" ID tubing; 20 micron Porex filter is in each end.
Uline Silica Gel Desiccants - Gram Size 5, 5 Gallon Pail
Silica Gel Desiccants - Gram Size 5, 5 Gallon Pail
Cole-Parmer Drierite 60018 Desiccant Bags, 8 oz/bag, 100 bags/pk
These nonwoven crepe bags are filled with Drierite (anyhydrous calcium sulfate) to completely dry the air within a package or container during shipment or storage. The bags are sturdy and held together by heat seals. Drierite bags also perform well in elevated temperatures and will not release absorbed moisture at less than 350°F.