A heteropoly acid ionic crystal containing Cr as an active catalyst for dehydration of monosaccharides to produce 5-HMF in water

Abstract

Cs2[Cr3O(OOCC2H5)6(H2O)3]2[α-SiW12O40], a chromium-based heteropoly acid (HPA) ionic crystal, was demonstrated to be an active heterogeneous catalyst for production of 5-hydroxymethylfurfural (HMF) from fructose or glucose.

Catalytic Isomerization of Biomass‐Derived Aldoses: A Review

“…[7] Interestingly,b oths olid and soluble Lewis acids have been proposed for such one-pot reactions. For example, CrCl 3 , [81] AlCl 3 , [87] and lanthanide salts [88] have been intensively studied for the one-pot conversion of glucosei nto HMF.An umber of reports considerc ombinations of Brønsteda cids with solid Lewis acids including Sn-b, [7] Nb 2 O 5 ·n H 2 O, [89] Cr-based heteropoly acid ionic crystal, [90] Ti phosphates, [91] and dealuminated b zeolite. [92] Nevertheless, there are some concernsr egardingt he long-term stability of zeolitesi nh ot water in the presence of Brønsted acids and salts.…”

Nb2O5-γ-Al2O3 nanofibers as heterogeneous catalysts for efficient conversion of glucose to 5-hydroxymethylfurfural

“…6A), and the best 5-HMF yield is about 59.0% over the catalyst with 0.5 wt% Nb 2 O 5 loading, while the yield is only 33.5% with 33.9 wt% Nb 2 O 5 loading. 59.0% 5-HMF yield over 0.5 wt% Nb 2 O 5 -γ-Al 2 O 3 nanofiber is significant which is higher than those reported in literatures202526. Nb 2 O 5 -γ-Al 2 O 3 nanofiber can well catalyze the conversion of fructose and xylose to 5-HMF and furfural, which is not as significant as glucose conversion (Fig.…”

Leather‐Promoted Transformation of Glucose into 5‐Hydroxymethylfurfural and Levoglucosenone

“…Owing to its instability, 5‐HMF requires careful tuning of the reaction parameters and/or a continuous extraction process to ensure high yields. The instability of 5‐HMF and the possibility of forming humins and other side products often leads to modest yields, which typically range from 20 to 70 % . Here, the yield of 5‐HMF was determined by 1 H NMR spectroscopy with CH 2 Br 2 as internal standard, and the identity of the product was further confirmed by GC‐MS (see Experimental Section and Figures S6–S9 for representative 1 H NMR spectra).…”

“…Cr loss from leather has even been observed in aqueous solutions, and mostly Cr III species are leached from the native leather . However, comparing the magnitude of leaching is difficult because leaching tests are not routinely reported in papers on catalysis research . Interestingly, with decreasing Cr content, LGO is formed in higher yields and in nearly the same quantity as 5‐HMF.…”