Direct conversion of starch to hydroxymethylfurfural in the presence of an ionic liquid with metal chloride

Abstract

Starch can be exploited as an abundant resource for sustainable production of diverse chemical intermediates such as hydroxymethylfurfural (HMF). We present a simple process of producing HMF from starches using an ionic liquid, 1-octyl-3-methylimidazolium chloride ([OMIM]Cl), and CrCl 2 catalyst. The addition of HCl and CrCl 2 significantly affected the yields of HMF on the whole. CrCl 2 increased the yields of HMF by approximately two-folds on average. The synthesis of HMF was most effective between 60 and 90 min reaction time at both concentrations of 0.3 and 0.5 M HCl. Starch concentration had influence on the productivity of HMF. At 20% starch concentration with 0.3 and 0.5 M HCl, its productivity was greatest (2.8 folds high). Eight starch sources (corn, wheat, rice, potato tuber, sweet potato, tapioca, acorn, and kudzu starch) were tested for the synthesis of HMF. The highest yields of HMF (73.0 AE 3.8 wt%) were obtained in tapioca starch dissolved in 0.5 M HCl.

Synthesis of 5‐(Hydroxymethyl)furfural in Ionic Liquids: Paving the Way to Renewable Chemicals

“…Hu et al [63] employed the SnCl 4 /[EMIm] [BF 4 ] system, by which an impressive HMF yield of 47 % from starch was obtained. A more extensive study was made by Chun et al [75] on the conversion of several different starch sources in 1-octyl-3-methylimidazolium chloride ([OMIm]Cl) with CrCl 2 as catalyst. The starch was initially dissolved in HCl before the addition of IL and catalyst.…”

Catalytic conversion of carbohydrates into 5‐hydroxymethylfurfural by Hafnium(IV) chloride in ionic liquids

“…Therefore, there is tremendous interest to develop new processes not only for fuels but also as a starting material for our chemical industry from carbohydrates [5,6]. 5-Hydroxymethylfurfural (HMF) is one of the top building block chemicals obtained from biomass [7] and it is recognized as a versatile and key precursor for the production of fine chemicals, polymeric materials and biofuels. Through oxidation, hydrogenation, hydrogenlysis, or aldol condensation, furan-2,5-dicarbaldehyde [8], 2,5-Furandicarboxylic acid [9], 2,5-dihydroxymethylfuran [10], 2,5-dimethylfuran [11] could be obtained from HMF.…”

Ionic Liquids as Tools for the Acid‐Catalyzed Hydrolysis/Dehydration of Saccharides to Furanic Aldehydes

“…[89] Besides decreasing the viscosity of the IL, which may improve mass transfer rates, [66][67][68] ACN may have an effect of leveling-off the acid strength of the reaction medium. [106] The reaction of cellulose (5 wt. such as ACN and DMSO, may influence the equilibrium of mutarotation of the hexoses (water concentration in the system may also influence the extent of this process), which may affect the selectivity of the catalytic system.…”

“…%) at 120 8C/1 h, using 0.5 m HCl in [omim]Cl (IL purity 98 %) coupled with AcOEt as somewhat immiscible co-solvent. [51,53,60,62,63,74,78,86,88,106,[109][110][111][112][113] Zhao et al have patented the application of such processes, and some of these represented major breakthroughs in the selective conversion of glucose and related di/polysaccharides into Hmf ( Figure 6). %) was investigated using (20 mol %) HCl and [emim]Cl as solvent, in a semi-batch operation mode, where water was gradually added, giving 30 mol % Y Hmf at 105 8C/4 h. [87] The reaction of Loblolly pine wood (5 wt.…”

“…%), and obtained 40 % Y Hmf (78 % C) within 2.5 min (MWH, 400 W, temperature not mentioned); this catalytic system was used for five batch runs without drop in Y Hmf (Table 3). [62,63,86,88,106,110,114] For the system CrCl 3 /[bmim]Cl/IBMK, our group reported Y Hmf of 37 wt. [62,63,86,88,106,110,114] For the system CrCl 3 /[bmim]Cl/IBMK, our group reported Y Hmf of 37 wt.…”