Environmentally Friendly Oxidation of Biomass Derived 5-Hydroxymethylfurfural into 2,5-Diformylfuran Catalyzed by Magnetic Separation of Ruthenium Catalyst

Abstract

In this study, aerobic oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-diformylfuran (DFF) was studied over a magnetic catalyst [Fe 3 O 4 @SiO 2 -NH 2 -Ru(III)]. Various reaction parameters were optimized for the oxidation of HMF into DFF. A high DFF of 86.4% and HMF conversion of 99.3% were obtained after 4 h at 120 °C. More importantly, the catalyst also showed high catalytic activity in air, and high HMF conversion of 99.7% and DFF yield of 86.8% were obtained after 16 h. The high catalytic performance of Fe 3 O 4 @SiO 2 -NH 2 -Ru(III) in air makes this method much more convenient and economical. Moreover, the procedure of the catalyst recycle was simple as the Fe 3 O 4 @SiO 2 -NH 2 -Ru(III) catalyst could be readily recovered from the reaction mixture by a permanent magnet. The catalyst could be reused several times without significant loss of its catalytic activity.

Ruthenium complex immobilized on poly(4-vinylpyridine)-functionalized carbon-nanotube for selective aerobic oxidation of 5-hydroxymethylfurfural to 2,5-diformylfuran

“…56 For Ru-PVP/CNT, there is an overlap between Ru 3d and C 1s peak at around 282.5 eV. 18,56 The presence of chlorine peak indicated that Cl − ion acts as the counter ion of Ru 3+ ion. 45 The binding energy at 461.8 and 484.2 eV are assigned to Ru 3p3/2 and Ru 3p1/2, respectively, which demonstrates that the oxidation state of the ruthenium species is Ru 3+ (Figure 8b).…”

“…45 The binding energy at 461.8 and 484.2 eV are assigned to Ru 3p3/2 and Ru 3p1/2, respectively, which demonstrates that the oxidation state of the ruthenium species is Ru 3+ (Figure 8b). 18,57 The N 1s binding energies are 397.0 and 397.4 eV for PVP/CNT and Ru-PVP/CNT, respectively ( Figure 8c). The observed shift in N 1s binding energies indicates that coordination bonds are presumably formed between nitrogen atom of pyridyl ligand and Ru 3+ ion in Ru-PVP/CNT.…”

“…In fact, the DFF selectivity is mainly determined by the reaction temperature, the solvent as well as the oxidant in this research. 17,18,32 In general, oxidant plays a vital role on the conversion rate of HMF and selectivity to DFF. As shown in Table 2, molecular oxygen, the clean and easily available oxidant, was most effective for the oxidation of HMF to DFF.…”

One‐Step Approach to 2,5‐Diformylfuran from Fructose by Using a Bifunctional and Recyclable Acidic Polyoxometalate Catalyst

“…Recently, Karimi and coworkers employed a magnetically separable catalyst (Fe 3 O 4 @SiO 2 -TEMPO) for the selective oxidation of HMF to DFF under metal-and halogen-free conditions. [19] In addition to organic catalysis, a series of transition-metal catalysts, such as vanadium, [20][21][22][23] manganese, [24,25] cobalt, [26] ruthenium, [27][28][29][30] copper, [31] iron, [32] silver, [33] and palladium, [34] were recently developed for HMF-to-DFF transformation and HMF conversion into 2,5-furandicarboxylic acid (FDCA) with molecular oxygen or air as the oxidants under a milder and more sustainable route.…”

金属担持触媒を用いたバイオマス由来アルコールの選択的酸化反応

“…Antonyraj et al reported total HMF conversion with 97 % DFF selectivity at 403 K under 0.28 MPa O2 after 4 h was achieved using Ru/γ-Al2O3 catalyst in toluene solvent 52) . Trimetallic mixed oxide RuCo(OH)2CeO2, which is active for aerobic oxidation of primary alcohols 53) , catalyzed HMF oxidation to DFF with 83 % yield at 97 % HMF conversion at 393 K in methyl isobutyl ketone solvent after 12 h 54 55) . The catalyst was magnetically separable and could be reused several times.…”