What Is Acrolein?
Acrolein, known as 2-propenal in IUPAC nomenclature, is an unsaturated aldehyde with a carbon-carbon double bond. It is a colorless or slightly yellowish liquid at room temperature with a strong pungent odor. It has a molecular weight of 56.06, a melting point of -88°C, and a boiling point of 53°C. This compound is produced during the thermal decomposition of fats and oils and is known for its toxicity and pungent odor.
Uses of Acrolein
Acrolein is used as a synthetic raw material for glycerin and allyl alcohol, and in the synthesis of pharmaceuticals such as methionine. It has applications in fiber treatment agents, cross-linking binders, and the production of colloidal osmium, rhodium, and ruthenium. It was historically used in resin components for paints but is less common now due to the prevalence of silicone resin paints. In medical research, acrolein is studied as a potential biomarker for cerebral infarction.
Principle of Acrolein
1. Properties of Acrolein
Acrolein is the simplest unsaturated chain aldehyde, highly reactive and prone to polymerization, especially in the presence of light, alkalis, and strong acids. Stabilizers like hydroquinone are often used to prevent oxidation and polymerization.
2. Synthesis of Acrolein
In laboratory synthesis, acrolein is produced by dehydrating glycerin with dehydrating agents like potassium hydrogen sulfate.
3. Chemical Reaction of Acrolein
Acrolein undergoes 1,4-nucleophile addition and participates in Michael addition reactions. It can be reduced to propanol via propionaldehyde.
Types of Acrolein
As an unstable compound, acrolein is not widely manufactured or sold. Available forms include aqueous solutions and methanol-water solutions at various concentrations, typically stored refrigerated or frozen.