Catalytic upgrading of renewable furfuryl alcohol to alkyl levulinates using AlCl3 as a facile, efficient, and reusable catalyst

The use of various aluminum salts as acid catalysts was compared in terms of catalytic upgrading of renewable furfuryl alcohol in hot ethanol medium. The commercially available AlCl 3 was emerged as a simple, cheap, and efficient catalyst for the synthesis of ethyl levulinate. From this study, four significant parameters including AlCl 3 dosage, furfuryl alcohol concentration, temperature, and time were evaluated and modeled to determine the optimal combination via response surface methodology with a central composite rotatable design. All parameters influenced the formation of ethyl levulinate—the maximum yield was 95.7% (100% furfuryl alcohol conversion). AlCl 3 could be recovered efficiently and reused multiple times without substantial loss of its catalytic activity. Moreover, AlCl 3 as the catalyst with optimized conditions was appropriate for the alcoholysis of furfuryl alcohol in other linear alcohols to afford equally high yields of the corresponding alkyl levulinates.