The sweet, viscous liquid that once served as a vital wartime defense priority
It is a colorless, odorless, and sweet-tasting liquid found in everything from your favorite cookies to life-saving medicines. While we know it as a common humectant, glycerol's chemical versatility once made it a cornerstone of national security during World War II.
Glycerol, a sugar alcohol with the chemical formula C3₃H₅(OH)₃, is a naturally occurring substance found in the triglycerides of both animal fats and vegetable oils. Because it possesses three hydroxyl groups, it is highly hygroscopic and miscible with water. This unique structure allows it to act as a powerful humectant, a role it plays in pharmaceuticals, skin care, and even food production, where it serves as a sweetener and a filler in low-fat items like cookies.
The molecule's utility extends far beyond the pantry. In the medical field, it is listed by the World Health Organization as an essential medicine for treating atopic eczema and is used to preserve red blood cells during freezing. Its ability to disrupt ice crystal formation—acting as a cryoprotectant—makes it invaluable for protecting laboratory organisms like bacteria and embryos. Furthermore, its high boiling point of 290°C and its ability to dampen vibrations allow it to be used as a fill for pressure gauges to prevent needle wear.
Historically, the importance of glycerol was defined by its chemical reactivity. During World War II, the ability to synthesize glycerol became a national defense priority because it serves as a precursor to nitroglycerin, an essential ingredient in explosives like dynamite and cordite. Today, the industry faces a new landscape: since approximately 2010, a large surplus of glycerol has emerged as a byproduct of biofuel production, driven by mandates such as EU directive 2003/30/EC. While crude glycerol can be purchased for as little as US$0.02–0.05 per kilogram, purifying it to high purity (greater than 99.5%) requires an expensive, multi-step distillation process.
Source: Glycerol
