Selective hydrodeoxygenation of 5-hydroxy-2(5H)-furanone to γ-butyrolactone over Pt/mesoporous solid acid bifunctional catalyst

Abstract

Selective hydrodeoxygenation of 5-hydroxy-2(5H)-furanone (HFO) derived from furfural oxidation to gbutyrolactone (GBL) provides a sustainable alternative to the petroleum-based process for gbutyrolactone production. Furfural is first converted to HFO through selective photocatalytic oxidation by using air oxygen as the oxidant (yield: 85.0%). HFO is further converted to GBL through hydrodeoxygenation over noble-metal nanoparticles on mesoporous Nb-Zr mixed oxides. The conversion of HFO to GBL involves two reactions: hydrogenation catalyzed by active metal and dehydration over mesoporous solid acids. The catalytic properties of M/Nb-Zr mixed oxides (M ¼ Pt, Ir, Ru, Rh and Pd) are related to the composition of support and active metal. The incorporation of zirconia into matrixes improves the thermal stability of mesoporous mixed oxides and increases the amounts of surface acid, which contributes to its catalytic selectivity to GBL. Pt/Nb 5 Zr 5 -550 exhibited the best catalytic performances with 97.3% selectivity of GBL at full conversion. The excellent performance can be correlated with the cooperative effect between active metal species and acid sites. The Pt-solid acid bifunctional catalysts show superior catalytic performance compared with conventional catalysts, such

Selective Production of Maleic Acid from Furfural via a Cascade Approach Combining Photochemistry and Electro- or Biochemistry

“…Recently, a similar approach was employed to synthesize γ-butyrolactone starting from furfural via 5-hydroxy-2(5H)-furanone as an intermediate. 46 Step 1: Synthesis of 2 via Photochemical Oxidation. The synthesis of 2 is well-documented in the literature: 1 is photochemically oxidized at room temperature by singlet oxygen generated using a catalytic amount of methylene blue as photosensitizer.…”

“…2 accounts for 30−60% of the speciation under acidic conditions (0 < pH < 4), with the conjugated base of FAA, 2b, being the dominant species at pH > 6. 46 The electrochemical oxidation of 1 to 3 using PbO 2 in sulfuric acid solutions has already been known for almost 100 years 26 and proceeds through the intermediate 2a. 37,38 Starting around 1970, Zverev, Mil'man, and co-workers published a series of works describing the electrochemical production of 2a and 3 starting from 1 using PbO 2 and carbon anodes, including the use of various mediators.…”

“…Since furfural is a highly reactive molecule, it is envisioned that converting it into a stable intermediate will circumvent undesirable byproduct formation under oxidation reaction conditions. Recently, a similar approach was employed to synthesize γ-butyro­lactone starting from furfural via 5-hydroxy-2­(5 H )-furanone as an intermediate …”

“…Under aqueous conditions, 2 is in equilibrium with various compounds, including its tautomer β-formyl­acrylic acid (FAA, 2a ) (Scheme ). 2 accounts for 30–60% of the speciation under acidic conditions (0 < pH < 4), with the conjugated base of FAA, 2b , being the dominant species at pH > 6 . The electrochemical oxidation of 1 to 3 using PbO 2 in sulfuric acid solutions has already been known for almost 100 years and proceeds through the intermediate 2a . , Starting around 1970, Zverev, Mil’man, and co-workers published a series of works describing the electrochemical production of 2a and 3 starting from 1 using PbO 2 and carbon anodes, including the use of various mediators. − As a result, 2a could be produced in near to quantitative yields (90–95%) with high current efficiency (CE) at 1.3 V vs saturated calomel electrode (SCE).…”

A Robust Mesoporous Al2O3‐Based Nanocomposite Catalyst for Abundant NOx Storage with Rational Design of Pt and Ba Species

“…With the success of utilizing the supramolecular templating approach for the compositional design, [7–12] emerging applications using non‐siliceous materials have been explored increasingly in this research field [13–16] . Metal‐supported catalysts have also been architected by using a wide variety of high‐quality mesoporous materials, though the crystallinity of metal oxide frameworks is amorphous and/or occasionally crystallized in part [17–22] . At the initial stage of this research area, this was unavoidable because complete crystallization of metal oxide frameworks leads to the collapse of ordered mesoporous structures with a significant decrease in their porosities.…”