Selecting the Appropriate Desiccant: A Wise Investment for Efficiency and Savings!

 Selecting the Appropriate Desiccant: A Wise Investment for Efficiency and Savings!

For manufacturers and distributors, achieving an effective active packaging solution is imperative in prolonging the shelf life of their products. Desiccants, compounds designed to create low humidity environments, are invaluable in mitigating moisture-induced deterioration. They play a pivotal role in extending product shelf life while upholding safety and effectiveness standards. Therefore, the choice of desiccant is of utmost importance. Desiccants find widespread use in the development, transportation, maintenance, and storage of various materials and products.

Opting for the most cost-effective or convenient solution doesn't necessarily equate to the most beneficial outcome. Inadequate quality or incorrect quantities of desiccants can lead to either excessive or insufficient moisture absorption, potentially affecting the longevity and effectiveness of your product. This could prove detrimental to both the company and end-users. Thus, dedicating time to select the appropriate quality and quantity of desiccants during product development and packaging not only increases the product's chances of success in the market but also assures end-users of its efficacy.

Key Considerations Before Choosing the Right Desiccant

When it comes to selecting the appropriate desiccant, several crucial factors demand your attention. These include parameters like LOD (Loss on Drying) and MAC (Moisture Adsorption Capacity) at low relative humidity and elevated temperatures. Equally significant is the type of container employed for packaging, shipping, and storage, as well as the available packaging headspace. These factors collectively determine the specific desiccant type required and its optimal packaging format.

Furthermore, it's imperative to factor in the anticipated temperature and relative humidity levels to which the product will be exposed.

Each of these variables is best addressed through the utilization of a particular desiccant type or a strategic combination of various desiccants. An effective desiccant functions by absorbing water vapor from the air, thereby reducing the relative humidity to a level where water cannot condense, essentially preventing the formation of dew.

Choose the Right Desiccant for Your Specific Needs

At Sorbead India, we recognize the critical importance of selecting the perfect desiccant for your requirements.

That's why we offer a diverse range of desiccants that can be tailored to meet a wide array of design and manufacturing parameters.

The key to ensuring the stability and integrity of your products lies in the incorporation of a suitable desiccant during both the initial design and storage phases. By carefully comparing the properties and capabilities of each desiccation product, you can pinpoint the one that best suits your needs and make a well-informed decision. Below, we introduce some of these desiccants.

Varieties of Desiccants

Silica Gel

Silica gel stands as a favored desiccant choice, particularly in the food and pharmaceutical industries, due to its inert, non-toxic, and exceptionally stable characteristics. It takes the form of a partially dehydrated version of polymeric colloidal silicic acid, characterized by its amorphous micro-porous structure. With interconnected pore openings spanning approximately 3-60 angstroms, it boasts an expansive surface area that attracts and retains water through adsorption and capillary condensation. This allows silica gel to adsorb up to 40% of its weight in water. Silica gel is particularly effective for products stored at consistent temperatures and high relative humidity levels. Notably, it exhibits high efficiency at temperatures below 25°C (77°F) and a relative humidity of 40% (Fig. 1 & 2). However, it's crucial to exercise caution as temperatures rise, as the desiccant may desorb water or experience a reduction in its adsorption capacity, similar to clay (Fig. 3).

Figure 1: Adsorption Rate (H?O) of Various Adsorbents

Figure 2: Moisture Adsorption Capacity (H?O) of Different Adsorbents

Molecular Sieve

Molecular sieves, also known as Synthetic Zeolite or aluminosilicates, exhibit a superior and faster moisture adsorption capacity when compared to silica gel or clay (Fig. 2). This makes them exceptionally well-suited for products that demand immediate protection against moisture-related deterioration.

One distinguishing characteristic of molecular sieves is the uniformity of the pore size openings within their crystal lattice structure. Thanks to this uniformity, molecular sieves possess a high adsorption capacity even under low relative humidity conditions, rendering them a cost-effective choice for desiccation. However, their uniform structure limits the release of moisture back into the packaging as temperatures rise, unlike silica gel or clay (Fig. 3). This is particularly crucial for packaged goods exposed to a broad spectrum of environmental conditions. Nevertheless, it's imperative to exercise caution when determining the appropriate dosage for products with specific relative humidity (RH) requirements.

Selecting the precise desiccant from within the molecular sieve range is just as critical as choosing the right type of desiccant. Molecular sieves are available in various varieties, including types 3A, 4A, 5A, 13X, carbon molecular sieve, and molecular sieve powder. Similarly, different types of silica gels exist, such as silica gel blue, silica gel white, and silica gel orange. Each of these variants possesses distinct properties tailored to meet the specific requirements of your products.

Both desiccants, silica gel and molecular sieve, find application in safeguarding drugs, active pharmaceutical ingredients (APIs), diagnostic kits, and medical devices against the detrimental effects of hydrolytic degradation induced by unbound water within the packaging headspace.

Montmorillonite Clay

Montmorillonite Clay is a naturally sourced, porous adsorbent that undergoes mining and drying to become suitable for desiccant applications. One of its significant benefits is its ability to be efficiently rejuvenated and reused at exceptionally low temperatures without experiencing significant degradation or expansion. Nonetheless, this characteristic also means that as temperatures increase, the clay tends to release moisture back into the container. Clay stands out as a cost-effective and efficient desiccant, especially when operating within the typical temperature and relative humidity ranges (Table 1).

                                                Table 1: Properties of Adsorbents

Calcium Oxide (CaO)

Calcium oxide (CaO) is an economical desiccant that proves highly effective when your products are exposed to high-temperature environments during storage or transportation. This substance, often referred to as quick lime, stands out for its exceptional moisture absorption capabilities, especially at low relative humidity levels when compared to alternative materials (Fig. 2). Calcium oxide finds its primary application in packaging dehydrated food items, where maintaining a low critical relative humidity is crucial.

Customers can make informed choices regarding the most suitable desiccants by considering the factors and requirements outlined above.