Renewable Gasoline, Solvents, and Fuel Additives from 2,3-Butanediol

摘要

2,3-Butanediol (2,3-BD) is a renewable alcohol that can be prepared in high yield from biomass sugars. 2,3-BD was selectively dehydrated in a solvent-free process to a complex mixture of 2-ethyl-2,4,5-trimethyl-1,3-dioxolanes and 4,5-dimethyl-2-isopropyl dioxolanes with the heterogeneous acid catalyst Amberlyst-15. The purified dioxolane mixture exhibited an antiknock index of 90.5, comparable to high octane gasoline, and a volumetric net heat of combustion 34% higher than ethanol. The solubility of the dioxolane mixture in water was only 0.8 g per 100 mL, nearly an order of magnitude lower than the common gasoline oxygenate methyl tert-butyl ether. The dioxolane mixture has potential applications as a sustainable gasoline blending component, diesel oxygenate, and industrial solvent.