Graphene Oxide Catalyzed Dehydration of Fructose into 5‐Hydroxymethylfurfural with Isopropanol as Cosolvent

Abstract

The design of green heterogeneous catalysts for the efficient conversion of biomass into platform molecules is a key aim of sustainable chemistry. Graphene oxide prepared from Hummers oxidation of graphite was proven to be a green and efficient carbocatalyst for the dehydration of fructose into 5‐hydroxymethylfurfural (HMF) in some three‐carbon and four‐carbon alcohol mediated solvent systems. HMF was obtained in up to 87 % yield in 90 vol % isopropanol‐mediated DMSO solvent. Some control experiments and analytical data showed that a small number of sulfonic groups and abundance of oxygen‐containing groups (alcohols, epoxides, carboxylates) have an important synergic effect in maintaining the high performance of graphene oxide.

Carbocatalysis: The State of “Metal‐Free” Catalysis

“…Moreover, GO resulted in a higher conversion into EMF than other acid catalysts such as concentrated H 2 SO 4 , p‐ TsOH, H 2 PW 12 O 40 , and Amberlyst‐15. The same group further reported the dehydration of fructose to HMF with GO as catalyst in conjunction with a 9:1 v/v isopropanol/DMSO solvent mixture 54. Similarly, hydrogen sulfate groups on GO were determined as the active catalytic sites, while numerous oxygen‐containing groups on GO were hypothesized to promote stronger affinities for fructose through hydrogen‐bonding interactions, resulting in higher reactivity than Amberlyst‐15.…”

Catalytic dehydration of hexose sugars to 5‐hydroxymethylfural

“…The outstanding electronic, mechanical, and electrical properties of graphene‐based materials have led to their use in a variety of fields, including catalysis. Wang et al . used metal‐free graphene oxide and obtained up to an 87% HMF yield in the 90 vol.…”

Efficient conversion of fructose to 5‐hydroxymethylfurfural by functionalized γ‐Al2O3 beads

“…However, further experiments are necessary to investigate its potential in practical applications . In contrast, heterogeneous acid catalysts that avoid the aforementioned disadvantage have been widely utilized for biomass conversion into 5‐HMF, such as supported heteropoly acids, metal phosphates, cation exchange resins, sulfated zirconia, Metal Organic Framework (MOFs), acid‐functionalized silicas, and C‐based solid acids . They have the advantage of being easily separated and recyclable, making them more suitable for industrial production applications.…”