Density functional theory study on the initial reactions of d-Xylose and d-Xylulose dehydration to furfural

Density Functional Theory Studies on the Hydrolysis of Levoglucosenone to 5-Hydroxymethylfurfural

“…The HMF formation mechanism from LGO or DH in the aqueous phase was further calculated using H 2 SO 4 as a catalyst. Based on the report by Fang et al, 24 H 2 SO 4 is dissociated into H + and HSO 4 − in the aqueous phase, but H + is considered to be adsorbed near the O − of HSO 4 − during the calculation. Reactions in Schemes 2 and 3 can be divided into a two-step hydration reaction and hydrogen shift reactions, which include dehydration, ring-opening, and ring-closing reactions.…”

Sustainable Valorisation and Efficient Downstream Processing of Giant Reed by High‐Pressure Carbon Dioxide Pretreatment

“…The latter derives from structural acetyl groups of the hemicellulose so it can be used as an indicator of the progress of its depolymerisation [34] . Furfural and HMF derived from the acid‐catalysed dehydration reaction of xylose and glucose, respectively [2,35] . The acidification of the medium is due to the formation of carbonic acid and the release of acetic acid.…”

“…[34] Furfural and HMF derived from the acid-catalysed dehydration reaction of xylose and glucose, respectively. [2,35] The acidification of the medium is due to the formation of carbonic acid and the release of acetic acid. After 6 h a significant decrease in xylose concentration from 8 to 6 g/L was observed while furfural concentration increased from 2 to 3 g/L.…”

One-pot furfural production from sustainable biomass-derived sugars using a functionalized covalent organic framework as a heterogeneous catalyst

“…Finally, according to the previous research, we propose a multi-step reaction that may be involved in the catalytic conversion of D-xylose into furfural, including 24,25 3. Since the TAPT-DHPA-COF was a mesoporous material, highly ordered channels, high surface area, and abundant acid sites, which could facilitate full contact with D-xylose, promote the rapid delivery of substrates, and enhance the reaction efficiency.…”

“…Finally, according to the previous research, we propose a multi-step reaction that may be involved in the catalytic conversion of d -xylose into furfural, including 24,25 (a) d -xylose rings open to form l -lyxose, (b) the formation of d -xylulose via the isomerization reaction, (c) the formation of 1,2-enediol intermediate, (d) three subsequent dehydration steps yielding furfural, (e) the side reaction of self-condensation into humin from above saccharide, intermediate products, and target products. On the base of the above results, the possible catalytic mechanism of TAPT-DHPA-COF for furfural production from d -xylose was schematically illustrated in Fig.…”