Frequently Whenever the term desiccant Is used, people automatically consider the 3 chief kinds of desiccants: Indicating Silica Gel, Molecular Sieve, and Clay desiccant. Those who have heard of other desiccants, like Calcium Oxide, Montmorillonite Clay and Calcium Sulphide, may or may not have a thorough understanding of those desiccant types. Recognizing how important proper discernment is where the use of desiccants is concerned, IMPAK has generated another reference to be utilised together with the information on the webpage at the Quick Links navigation menu on the left for properly evaluating application needs and deciding on the correct desiccant for those apps. For a broader comparison, please refer to our Chart Comparisons page.
Montmorillonite Clay, Silica Gel, Indicating Silica Gel, Molecular Sieve, Calcium Oxide, Calcium Sulphate, Added Adsorbents. Montmorillonite Clay is a naturally occurring adsorbent generated by the controlled drying of magnesium aluminum silicate of the sub-bentonite type. This clay will regenerate for repeated use at very low temperatures without significant swelling or corrosion. However, this property causes clay to give up moisture readily back to the container as temperatures rise. Clay is a good Standard desiccant that works satisfactorily under 120°F roughly 50°C. Above 120° F, there is a possibility that the clay will give up moisture instead of pulling it in, so anticipated storage and transportation conditions should be considered. The upside to clay is that it is normally the cheapest desiccant each pound.
Clay is highly Successful in normal temperature and relative humidity ranges. Its appearance is that of small Gray pellets. Care has to be taken to make certain any low level impurities in the clay are not incompatible with the packed item. It is a naturally occurring mineral that is processed and processed to either granular or beaded form. As a PHARMACEUTICAL DESICCANT, it is a mean pore size of 24 angstroms and has a strong affinity for moisture molecules. The silica gel will pull in moisture at temperatures up to 220°F 105°C. As temperature goes above 100°F, the rate of moisture pickup will slow down but the silica gel will still work. Silica gel Performs best at room temperatures 70° to 90°F and greater humidity 60 to 90 percent RH and will fall the relative humidity in a container down to about 40 per cent RH. In the us, silica gel is often utilized in food and pharmaceutical applications as only silica gel has been approved by the FDA for direct contact with these products.