High yield conversion of cellulosic biomass into 5-hydroxymethylfurfural and a study of the reaction kinetics of cellulose to HMF conversion in a biphasic system

Abstract

Catalytic technology for cellulosic biomass conversion has been proven to be a promising approach for valuable chemical feedstock production. However, its recalcitrant nature is a major limitation to unlocking the carbohydrate biopolymer content and their subsequent conversion into 5-hydroxymethylfural (HMF). This paper investigates the production of HMF using glucose, cellulose, sugarcane bagasse and rice husk as the feedstocks. Acid dehydration of the carbohydrate sources was conducted in a biphasic system of water–MeTHF modified with N-methyl-2-pyrrolidone (NMP) over a phosphated TiO₂ catalyst. The catalyst displayed a very good catalytic performance for the conversion of glucose into HMF (91% yield). More so, it is suitable for the selective conversion of mechanocatalytic depolymerized cellulose to 74.7% yield of HMF. Cellulosic biomass could also be directly converted into HMF and furfural in reasonable yields. The efficiency of biomass-to-HMF production was further advanced after biomass fractionation treatment. Remarkable yields of 72% and 65% HMF were produced from sugarcane bagasse and rice husk, respectively. Finally, the reaction kinetics of solubilized cellulose to HMF conversion was investigated and a simplified kinetic model comprising two reaction steps was developed: (1) hydrolysis of cello-oligomers to glucose and (2) glucose dehydration to HMF.