Acid Catalyzed Degradation of Cellulose in Alcohols

Abstract

Cellulose is degraded by alcohols and strong acid-catalysts at 180°C to 200°C within minutes. Alkylglucosides, 5-alkoxyrnethylfurfurals, and alkyl levulinates plus alkyl formates are formed in consecutive reactions, accompanied by some humic residue. The scope of the reaction was explored by using C₁-, C₂-, C₃-, and C₄-alcanols and by combining various lignocellulosic substrates with methanol. Effects of catalysts and co-solvents were tested, resulting in more selective reactions and suppressing dialkylether formation of the solvent. Yields of 46% methyl levulinate, 44% ethyl levulinate, and 37% n-propyl levulinate (based on theory) from cellulose point to the preparative value of the reactions.