Glycerol
[CAS# 56-81-5]

Identification

• Classification: API >> Digestive system medication >> Laxative antidiarrheal
• Name: Glycerol
• Synonyms: Glycerine; 1,2,3-Propanetriol
• Molecular Formula: C₃H₈O₃
• Molecular Weight: 92.09
• CAS Registry Number: 56-81-5
• EC Number: 200-289-5
• FEMA: 2525
• SMILES: C(C(CO)O)O

Properties

• Density: 1.25
• Melting point: 18 °C
• Boiling point: 290 °C
• Refractive index: 1.452-1.475
• Flash point: 160 °C
• Water solubility: >500 g/L (20 °C)

Safety Data

• Hazard Symbols: GHS07 Warning
• Risk Statements: H319
• Safety Statements: P264-P337+P313-P305+P351+P338

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Eye irritation	Eye Irrit.	2	H319
Skin irritation	Skin Irrit.	2	H315
Acute toxicity	Acute Tox.	2	H300
Specific target organ toxicity - repeated exposure	STOT RE	2	H373
Specific target organ toxicity - repeated exposure	STOT RE	1	H372
Specific target organ toxicity - single exposure	STOT SE	3	H335
Eye irritation	Eye Irrit.	2A	H319
Specific target organ toxicity - repeated exposure	STOT RE	2	H372
Skin corrosion	Skin Corr.	1	H314
Serious eye damage	Eye Dam.	1	H318
Acute toxicity	Acute Tox.	4	H332

Discovery and Applications

Glycerol, also known as glycerin or glycerine, is a simple polyol compound with the molecular formula C3H8O3. It is a colorless, odorless, and viscous liquid that has a sweet taste and is non-toxic. Glycerol is a key component in the structure of lipids known as triglycerides, which are found in fats and oils. It was first discovered in 1779 by the Swedish chemist Carl Wilhelm Scheele, who obtained it by heating a mixture of olive oil and lead monoxide. This discovery marked the beginning of glycerol’s long history of applications across various industries.

One of the earliest and most significant applications of glycerol was in the production of nitroglycerin, a highly explosive compound that is also used medically to treat heart conditions such as angina pectoris. Nitroglycerin is made by nitrating glycerol, and it played a crucial role in the development of explosives in the 19th century. Beyond its use in explosives, glycerol's role in pharmaceuticals has expanded significantly due to its safe and versatile properties.

In the pharmaceutical industry, glycerol is commonly used as a solvent, humectant, and emollient. It helps to maintain moisture in products such as creams, ointments, and lotions, making it a valuable ingredient in skin care products. Glycerol’s moisturizing properties are beneficial in treating dry skin conditions, and it is also used as a sweetening agent in syrups and elixirs due to its pleasant taste.

Glycerol’s versatility extends to the food industry, where it is utilized as a humectant, solvent, and sweetener. It helps to preserve moisture in food products, preventing them from drying out, and it can be found in a wide range of food items, including baked goods, candies, and beverages. As a sweetener, glycerol is particularly valuable in low-calorie foods because it provides sweetness without adding significant calories.

In addition to its use in food and pharmaceuticals, glycerol is also employed in the production of personal care products, such as toothpaste, where it acts as a humectant to prevent the toothpaste from drying out. Glycerol’s ability to form a smooth paste makes it an ideal ingredient in various cosmetic and grooming products.

The compound also has applications in industrial processes. For example, glycerol is used in the manufacture of polyurethanes and alkyd resins, which are important in the production of foams, coatings, and adhesives. In the textile industry, glycerol is used as a lubricant and plasticizer, and it plays a role in the production of antifreeze formulations, where its low freezing point and non-toxic nature are advantageous.

In the field of biotechnology, glycerol serves as a cryoprotectant, which is a substance used to protect biological tissue from freezing damage during cryopreservation. Its ability to lower the freezing point of water and reduce ice crystal formation makes it an essential component in the preservation of cells, tissues, and organs.

More recently, glycerol has gained attention as a renewable feedstock in the production of biofuels and biochemicals. As a byproduct of biodiesel production, glycerol is abundant and can be converted into valuable chemicals such as propylene glycol and epichlorohydrin, which are used in various industrial applications. The exploration of glycerol as a sustainable resource highlights its importance in the transition to greener technologies and processes.

In summary, glycerol is a versatile and widely used compound with applications ranging from pharmaceuticals and food to industrial processes and biotechnology. Its discovery over two centuries ago has led to its integration into numerous products and industries, making it an indispensable chemical in modern society.

References

2025. Heterogeneous porous hypoxia-mimicking scaffolds propel urethral reconstruction by promoting angiogenesis and regulating inflammation. Biomaterials, 312.
DOI: 10.1016/j.biomaterials.2024.122833

2025. Effects of different ratios of water and glycerol on the physicochemical properties of starch-based straws. Food Chemistry, 464.
DOI: 10.1016/j.foodchem.2024.142215

1853. Botanischer Tauschverein in Wien. Österreichisches botanisches Wochenblatt, 3.
DOI: 10.1007/bf02060206