Selective and recyclable depolymerization of cellulose to levulinic acid catalyzed by acidic ionic liquid

Kinetic study of glucose conversion to levulinic acid over Fe/HY zeolite catalyst

“…Meanwhile, higher activation energies were attained for other homogeneous acid catalysis reactions. As shown in Table 2, the activation energy for 5-HMF conversion to LA was not reported for reactions involving ionic liquids [40,41,49,50]. On the other hand, the activation energy of glucose conversion directly to LA was reported (202 kJ.mol -1 ) as the formation reaction of 5-HMF was not included in the kinetic model [50].…”

“…The dissociation constant of the catalyst used (H 2 SO 4 ) was also considered in the kinetic model. Table 2 include non-catalyzed glucose conversion reaction [30] and the use of various catalysts such as mineral acids [7,[26][27][28][29], chromium chloride and ionic liquids [40,41,49,50]. Previous studies reported activation energies for mineral acid catalyzed glucose conversion to 5-HMF in the range of 86 -160 kJ.mol -1 [7,[26][27][28][29], while for non-catalyzed glucose decomposition was 108 kJ.mol -1 [30].…”

“…This study reported a value of 64 kJ.mol -1 , which is lower compared to previous studies involving mineral acids and non-catalyzed conversion reaction. Meanwhile, a large range of activation energies (56 -202 kJ.mol -1 ) was obtained for glucose to 5-HMF in ionic liquids [40,41,49,50]. Most of the studies reported the activation energy of glucose to 5-HMF without considering the formation of intermediates.…”

New Frontiers in the Catalytic Synthesis of Levulinic Acid: From Sugars to Raw and Waste Biomass as Starting Feedstock

“…Ionic liquids are salts consisting of ions which are liquid at ambient temperatures or below 100 • C [135]. The stability, the low vapor pressure, the easy separation and recyclability of ionic liquids, coupled with the fact that their physical and chemical properties can be easily tuned by varying the ions, are some of the important reasons for the intense interest for the use of these solvents to convert raw biomass into added-value products [136][137][138][139][140][141][142]. Catalytic conversion of biomass to LA in the ionic liquid [EMIM][Cl] using a hybrid catalyst (CrCl 3 and HY-zeolite) has shown to yield 46 wt % of LA from cellulose working at 61.8 • C for 14.2 min.…”

Conversion of Fructose into Levulinic Acid by Catalysis of Ionic Liquid

“…In our previous work, it was found that SO 3 Hfunctionalized acidic ionic liquids especially 1-methyl-3-(3-sulfopropyl)imidazolium hydrogen sulfate ([C 3 SO 3 Hmim] HSO 4 ), are environmentally friendly catalysts to convert cellulose into LA with high yield and selectivity [8,9]. Herein, we report on the acidic ionic liquid-catalyzed fructose conversion to platform chemical LA in a yield up to 76% (Scheme 1), whereas chemical structure and morphology of humin byproducts were investigated under the same reaction conditions.…”