Süd-Chemie Expands Offerings In Clay Based Desiccants
Süd-Chemie Inc. (Belen, NM) is promoting the benefits of Bentonite clay desiccants, in an expanded line of products using the substance. The clay-based desiccant’s advantages include a higher adsorption capacity than silica gel desiccants at the lower humidity levels that commonly prevail in pharmaceutical packaging, Süd-Chemie claims.
More customers are requesting the clay desiccant because of its performance advantages, the clay’s more environmentally friendly profile versus silica gel, and cost advantages that have prevailed in recent years, says Mark Florez, global marketing manager, Süd-Chemie, Performance Packaging. “We had been offering the Bentonite clay in all of our bag, packet, and canister formats, but only in certain sizes, and often on a customer-request basis. We now provide a standard line of Desi-Pak and Desi-Can Bentonite clay products in all the configurations in which we offer silica gel, and we have expanded its use into our stopper line,” Florez says.
|Süd-Chemie's desiccant caps.|
Though silica gel remains the standard for many drug packaging and medical device applications, a “perfect storm” of factors is driving interest in Bentonite clay, Florez says.
Price rises for sulfuric acid used in making silica gel have fueled production costs and silica gel prices in recent years. “With the increase in these costs, we can offer Bentonite products with a price incentive as compared with silica gel,” says Florez.
Bentonite has environmental benefits, from production and transportation standpoints, the company reports. As silica gel is made in a complex manufacturing process, and is typically sourced from China, it creates a significant carbon footprint. A chemically inert hydrated aluminum silicate, Bentonite is extracted from Süd-Chemie global reserves that include a mine site in Arizona. Processing requires only extrusion and drying.
The clay desiccant is suited to pharmaceutical applications, where controlled packaging environments and internal package moisture levels rarely exceed 40%. In package conditions below 30% RH, Bentonite absorbs a higher percentage of its weight in moisture than an equivalent amount of silica gel. Thus, the substance provides better moisture control over time in that RH range for ensuring product shelf life, Süd-Chemie says.
|Comparisons of silica gel with bentonite. Süd-Chemie claims clay-based desiccants have a higher adsorption capacity than silica gel desiccants at the lower humidity levels that commonly prevail in phrarmaceutical packaging.|
Bentonite is nothing new to the pharmaceutical industry as it is often used as a binder, suspending agent, emulsion stabilizer, or adsorptive additive in pharmaceutical formulations. Florez notes that companies wishing to convert from silica gel to Bentonite clay can typically submit a CBE (Changes Being Effected) supplement or CBE-30 for approved NDA and ANDA products.