Mechanocatalytic Depolymerization of Dry (Ligno)cellulose As an Entry Process for High-Yield Production of Furfurals

Abstract

Driven by mechanical forces, the acid-catalyzed depolymerization of solid biomass completely overcomes the problems posed by the recalcitrance of lignocellulose. The solid-state reaction leads to water-soluble oligosaccharides, which display higher reactivity than cellulose and hemicellulose. Here, we show that water-soluble oligosaccharides are useful feedstock for the high-yield production of 5-hydroxymethylfurfural (HMF) and furfural in biphasic reactors. This is because they readily undergo hydrolysis upon microwave heating, selectively forming monosaccharides as intermediates in the aqueous phase. Short reaction times are possible with the use of microwave heating and limit the extent of degradation reactions. This work provides an ionic-liquid-free approach to process lignocellulosic substrates into HMF and furfural with high yields. In fact, starting this novel approach with alpha-cellulose, yields of HMF of 79% and furfural of 80% at 443 K for 9 min were obtained. The processing of real lignocellulose (e.g., beechwood and sugar cane bagasse) also achieved high yields of HMF and furfural. Thereby, the current results indicate that the process limitation lies no longer in the recalcitrance of lignocellulose, but in the extraction of highly reactive HMF and furfural from the aqueous phase in the biphasic reactor

Production of furfural from xylose, water-insoluble hemicelluloses and water-soluble fraction of corncob via a tin-loaded montmorillonite solid acid catalyst

“…Moreover, a significant enhancement of the furfural yield as well as the selectivity was achieved in the biphasic system (Table 2, entries 12 and 13). These results were consistent with the reported in literatures (Carrasquillo-Flores et al, 2013;Guerbuez et al, 2012). The addition of NaCl to the biphasic system can greatly improve the partitioning of furfural into the organic phase by altering the intermolecular bonding interactions between liquid components, thus increase the immiscibility between the aqueous phase and the organic phase (Nikolla et al, 2011).…”

“…Thereafter, water as well as some other solvents (ionic liquids and organic solvents) have been widely applied for the furfural synthesis under various conditions (Wei et al, 2011;Zhang et al, 2013). Recently, a new biorefining strategy for converting the biomass to the furan compounds by utilizing biphasic systems was proposed (Carrasquillo-Flores et al, 2013;Guerbuez et al, 2012). In biphasic systems, target products are transferred from the aqueous phase to the organic phase once produced, thus ceases interfering side reactions (Daengprasert et al, 2011;Ordomsky et al, 2013;Pagan-Torres et al, 2012).…”

Targeted chemical upgrading of lignocellulosic biomass to platform molecules

“…151 Dutta et al 152 converted sugarcane bagasse into ethoxymethylfurfural (EMF), a fuel additive, by using metal chlorides in DMA-LiCl and ionic liquids ([BMIM]Cl) with ethanol. In a first step, they obtained HMF yields of 42% from sugarcane bagasse in the presence of Zr(O)Cl 2 /CrCl 3 and using [BMIM]Cl as a solvent.…”

Mechanocatalytic Production of Lactic Acid from Glucose by Ball Milling

“…Among its various applications, the mechanocatalysis of biomass has gained much attention because of its potential to be a green and practical pathway in biomass pretreatment. Lignocellulose can be more efficiently converted into sugars, alcohols, furfurals, and other biomassderived chemicals after being pretreated by mechanochemical processes [14,15]. Cellulose and lignin were ball milled after being mixed with acidic and basic solid catalysts, respectively, and it was found that the mechanocatalysis process could depolymerize the substrates and result in water-soluble fractions, since the β-1,4 glyosidic bond and β-O-4 linkage can be cleaved by a synergistic effect between the solid catalyst and mechanical forces [16−18].…”