Biodiesel Chemical | Chemical Industry

Biodiesel refers to a mixture of fatty acid alkyl esters, typically derived from vegetable oils or animal fats through transesterification. 

Its general chemical formula is CH₃(CH₂)ₙCOOCH₃ for the common methyl ester form, where n varies (usually 10–18) based on the fatty acid chain length.

Production Process

Biodiesel forms via transesterification, where triglycerides react with methanol (or another alcohol) in the presence of a catalyst like sodium hydroxide. This yields fatty acid methyl esters (FAME, the biodiesel component) and glycerol as a byproduct.

The reaction simplifies as: 

Triglyceride + 3 CH₃OH ⇌ 3 FAME + Glycerol.

Common Variants

Different feedstocks produce specific esters; for example, rapeseed methyl ester (RME) from oleic acid (C18:1) has a molecular mass around 296 g/mol.