Starbon/High‐Amylose Corn Starch‐Supported N‐Heterocyclic Carbene–Iron(III) Catalyst for Conversion of Fructose into 5‐Hydroxymethylfurfural

Abstract

Iron-N-heterocyclic carbene complexes (Fe-NHCs) have come to prominence because of their applicability in diverse catalytic reactions, ranging from C-C cross-coupling and C-X bond formation to substitution, reduction, polymerization, and dehydration reactions. The detailed synthesis, characterization, and application of novel heterogeneous Fe-NHC catalysts immobilized on mesoporous expanded high-amylose corn starch (HACS) and Starbon 350 (S350) for facile fructose conversion into 5-hydroxymethylfurfural (HMF) is reported. Both catalyst types showed good performance for the dehydration of fructose to HMF when the reaction was tested at 100 °C with varying time (10 min, 20 min, 0.5 h, 1 h, 3 h and 6 h). For Fe-NHC/S350, the highest HMF yield was 81.7 % (t=0.5 h), with a TOF of 169 h , fructose conversion of 95 %, and HMF selectivity of 85.7 %, whereas for Fe-NHC/expanded HACS, the highest yield was 86 % (t=0.5 h), with a TOF of 206 h , fructose conversion of 87 %, and HMF selectivity of 99 %. Iron loadings of 0.26 and 0.30 mmol g were achieved for Fe-NHC/expanded starch and Fe-NHC/S350, respectively.

A novel molybdenum oxide–Starbon catalyst for wastewater remediation

“…Pure Expst and Mo-Expst show two prominent absorption bands at 3300 and 1000 cm À1 which are due to the O-H and C-O stretching vibrations, respectively, present in the starch precursor. 22 The intensity of these bands diminishes as a result of carbonization. The IR spectra of…”

“…The rst mass loss occurs around 100 C, which is attributed to the desorption of physically adsorbed water molecules from the surface and pores of the material. 22 The characteristic decomposition prole of expanded starch (Pure Expst) is observed with a strong endothermic transition at approx. 195 C. This transition occurs at approx.…”

Late Transition Metal (LTM)-NHC Catalyzed Transformations of Renewable Chemicals to Fine Chemicals, Fuels, and Intermediates

“…A new heterogeneous and recyclable Fe-NHCs immobilized on mesoporous expanded starch and Starbon™ 350 could be utilized successfully for the effective dehydration of fructose to HMF [36].…”

An Excellent Solid Acid Catalyst Derived from Microalgae Residue for Fructose Dehydration into 5‐Hydroxymethylfurural

“…Among these various candidates, carbonaceous solid acids have attracted considerable attentions as efficient catalysts because of their relatively strong Brönsted acidity of oxygen‐ and sulfur‐containing functional groups together with the green, convenient and stable natures . Most of these studies have been carried out in organic solvents ,. Although relatively high yields of 5‐HMF have been achieved, the drawbacks like environmental pollution, expensive solvents, difficult separation of products etc strongly prevent their industrialization …”

“…After large‐scale productions of biogas, biobutanol, bioethanol etc from microalgae, amounts of defatted microalgae residue remains and has always been discarded as waste. Normally, the remnant biodiesel waste is notably rich in algal carbohydrates, proteins etc, which indicates that microalgae residue might be a potential bio‐resource for preparing carbon catalysts owing to its low cost and easy sustainability ,. Accordingly, it could be an active research topic to exploit the waste microalgae residue, as well as to utilize this waste residue to produce staple or value‐added platform chemicals.…”