One‐Pot 2‐Methyltetrahydrofuran Production from Levulinic Acid in Green Solvents Using Ni‐Cu/Al₂O₃ Catalysts

Abstract

The one-pot hydrogenation of levulinic acid to 2-methyltetrahydrofuran (MTHF) was performed using a series of Ni-Cu/Al2 O3 catalysts in green solvents, such as water and biomass-derived alcohols. Ni/Al2 O3 provided the highest activity, whereas Cu/Al2 O3 was the most selective, reaching a 75 % MTHF yield at 250 °C after 24 h reaction time. Synergetic effects were observed when bimetallic Ni-Cu/Al2 O3 catalysts were used, reaching a 56 % MTHF yield in 5 h at 250 °C for the optimum Ni/Cu ratio. Remarkably, these high yields were obtained using non-noble metal-based catalysts and 2-propanol as the solvent. The catalytic activity and selectivity results are correlated to temperature programmed reduction (TPR), XRD, and STEM characterization data, identifying the role associated with mixed Ni-Cu particles in addition to monometallic Cu and Ni.

xNi–yCu–ZrO2 catalysts for the hydrogenation of levulinic acid to gamma valorlactone

“…Extra reduction signals between 250 and 400 °C were observed in both 35Ni-15Cu-ZrO 2 and 45Ni-5Cu-ZrO 2 which likely corresponds to the lower temperature reduction of NiO facilitated by the presence of Cu. The facile reduction of NiO due to interaction of Cu has been well documented by Arias and co-workers [26]. It is also possible that the reduction signal between 250 and 400 °C was due to the Cu-Ni alloy suggested by the XRD data ( Figure 4).…”

“…This catalyst was also used by the same research group to hydrogenate LA using formic acid as a H 2 source, and was stable up to 100 h on stream [25]. Arias and co-workers investigated the effect of Ni-Cu catalysts supported on Al 2 O 3 for LA hydrogenation to 2-MTHF, which occurs via GVL as an intermediate [26]. Ni/Al 2 O 3 was found to be the most active catalyst, and Cu/Al 2 O 3 the most selective to 2-MTHF.…”

“…The most active catalyst (45Ni-5Cu-ZrO 2 ) has both the highest BET surface area and a high specific adsorption of N 2 O with small metal particle sizes, indicating high metal dispersion in this material. The high dispersion coupled with low Cu content may also lead to more regions of exposed Ni metal available to catalyse hydrogenation [26,41].…”

Recent Advances in the Catalytic Production of Platform Chemicals from Holocellulosic Biomass

“…At present, MF is formed as a by‐product in the formation of furfuryl alcohol from FUR. Even though MTHF has a lower octane number (87) than ethanol (108.6), MTHF shows more fitting biofuel aspects due to its hydrophobicity, it has a higher density and a higher heating value . Therefore it is employed with ethanol and gas to create an alternative fuel that can be used as a substitute for gasoline (P‐Series Fuel).…”

A Computational Kinetics Study on the Intramolecular Hydrogen Shift Reactions of Alkylperoxy Radicals in 2‐Methyltetrahydrofuran Oxidation

“…In a recent work, Dong et al report first one‐step conversion of furfural into 2‐MTHF that resulted in high yield (97.1%) under the atmospheric pressure. A one‐pot synthesis approach of 2‐MTHF was reported from levulinic acid using bimetallic Ni‐Cu/Al 2 O 3 as a catalyst in a green solvent. The reported yield from this approach is 56% in 5 h at 250°C for optimum Ni/Cu ratio.…”