Used as an ionic liquid catalyst in esterification, alkylation, transesterification, and biodiesel production due to its strong acidity and high thermal stability. Facilitates efficient conversion of free fatty acids and triglycerides into fatty acid methyl esters with minimal side reactions. Exhibits good recyclability, maintaining activity over multiple reaction cycles. Also applied in cellulose processing and as a solvent in organic synthesis where acidic conditions are required. Its polar nature enhances solubility of biomass components, making it suitable for biorefinery applications.