Ionic Liquid Binary Mixtures, Zeolites, and Ultrasound Irradiation: A Combination to Promote Carbohydrate Conversion into 5-Hydroxymethylfurfural

Abstract

The efficient conversion of biomass into value-added compounds under mild and safer conditions is a cornerstone of present research efforts to meet the needs of the chemical industry with sustainable development. In this work, we studied the dehydration of fructose, glucose, and sucrose into 5-hydroxymethylfurfural (5-HMF), catalyzed by HY zeolite, in three ionic liquid mixtures differing for the cation, aromatic, or aliphatic. We investigated the effect of several operational parameters such as temperature, catalyst loading, zeolite counterion, solvent mixture, and added chloride. In the optimal experimental conditions, we obtained good conversions to 5-HMF especially for fructose and sucrose, 73% and 62%, using the relatively low temperatures of 80 and 120 °C, respectively. Interestingly, in the used experimental conditions, the solvent−catalyst systems can be reused for at least 6 cycles without loss in performance. We also investigated the dehydration of fructose under sonochemical activation, obtaining a conversion to 5-HMF of 71% in 0.5 h, at the remarkably low temperature of 40 °C.

Intermolecular and Intramolecular Friedel‐Crafts Acylation of Carboxylic Acids using Binary Ionic Liquids: An Experimental and Computational Study

“…The development of benign synthetic pathways has attracted much attention in organic transformations for academic and industrial research [20–21] . In the last two decades, ionic liquids have been employed in various fields, especially in organic synthesis and catalysis, due to their unique properties, including negligible vapour pressure and high thermal stability [22] . The limitation of ionic liquids for industrial application is the high cost, toxicity, and complicated preparation [23] .…”

Catalytic Dehydration of Fructose to 5-Hydroxymethylfurfural in Aqueous Medium over Nb2O5-Based Catalysts

“…Due to the great potential of HMF as a versatile platform molecule, its production has been approached by different methodologies [ 8 ], trying to minimize side reactions and/or HMF further transformation. Although many endeavors have been devoted to HMF production from glucose or fructose in water, organic solvents or ionic liquids, the intrinsic reaction efficiency is still low [ 9 , 10 , 11 , 12 , 13 , 14 ]. A brown coloration of the reaction mixtures is generally observed, indicating the formation of polymeric bio-products, i.e., humins [ 15 ].…”

Continuous‐Flow Synthesis of 5‐Hydroxymethylfurfural, Furfural from Monosaccharides: A Simple, Fast, and Practical Method

“…[29][30][31] Recently, it is also reported that ionic liquids can enhance the rate of formation of HMF from fructose. [22,[32][33][34] Additionally, ionic liquids have been shown to be effective in the synthesis of HMF using ionic liquid/organic solvent as a biphasic system. [35][36][37][38] Although interesting results could be obtained, the large-scale industrial feasibility of these approaches is limited.…”

“…They have been promising solvents for biomass pretreatment and conversion due to their unique properties, such as negligible volatility, a wide range of liquid existence, high dissolution rates, excellent thermal stability, possible tailoring, and recyclability, they have been defined as green solvents for biomass pretreatment and conversion [29–31] . Recently, it is also reported that ionic liquids can enhance the rate of formation of HMF from fructose [22,32–34] . Additionally, ionic liquids have been shown to be effective in the synthesis of HMF using ionic liquid/organic solvent as a biphasic system [35–38] .…”