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Biomass‐derived feedstocks play a vital role in sustainable economies for renewable energy, waste management, energy security, and commercial prospects. This study focused on promoting the ring hydrogenation of furfural (FAL) into tetrahydrofurfuryl alcohol (THFA) in an aqueous solution using a potential Ni−Re‐supported hydrotalcite‐derived MgAl catalyst at different Ni : Re molar ratios. Structural analyses, such as an in situ time‐resolved X‐ray absorption near edge structure, under H2 reduction elucidated the simultaneous transformation of Re6+ and Re7+ to Re0 with the remaining highly stable Ni2+. The construction of Ni−Re on hydrotalcite‐derived MgAl catalyst resulted in the alleviated H2 reduction behavior, facilitated H2 adsorption and desorption processes, and suitable catalyst acidity detected by H2 temperature‐programmed reduction, and H2 and NH3 temperature‐programmed desorption experiments, respectively. Under optimized conditions, a maximum THFA yield of 78 % with a complete FAL conversion was attained using Ni1Re0.16/MgO−Al2O3 catalyst at a reaction temperature of 140 °C, H2 pressure of 20 bar, catalyst loading of 20 %, and reaction time of 2 h in a H2O system. Isotopic deuterium (D2O) labeling revealed that D substitution was notably pronounced through isotopic exchange between the D atom from D2O and H atom in FAL during its hydrogenation to THFA. [ABSTRACT FROM AUTHOR]

Catalytic thermochemical conversion offers a sustainable method to upgrade oil‐based feedstocks into highly valuable biofuel, aligning with the modern biorefinery concept. Herein, a series of IrRe/SAPO‐11 catalysts with different Ir to Re molar ratios compared to reference Ir/SAPO‐11 and Re/SAPO‐11 catalysts was prepared using a wetness impregnation method. These catalysts were used for the direct production of sustainable aviation fuels (SAFs) via efficient hydrodeoxygenation and hydroisomerization of triglycerides. The catalyst screening confirmed that the optimum IrRe/SAPO‐11 catalyst, with an equivalent Ir to Re molar ratio, exhibited the highest hydrodeoxygenation activity under milder operation conditions than the conditions used in previous studies. Increasing the reaction temperature up to 330 °C enhanced the formation of iso‐alkanes in the liquid product, achieving a freezing point of −31.4 °C without additional cold flow improvers. Furthermore, a long‐term stability experiment demonstrated that the developed Ir−Re system exhibited exceptional performance over 150 h. This excellent catalytic activity and stability of the bifunctional IrRe/SAPO‐11 catalyst was owing to its suitable interface between metallic and oxide sites, mixed mesoporous structures, reduced catalyst size, and increased Lewis acid ratio, as confirmed by our comprehensive characterizations. [ABSTRACT FROM AUTHOR]

Selective hydrogenation and hydrogenolysis of 5‐hydroxymethylfurfural (HMF) to 2,5‐bis(hydroxymethyl)furan (BHMF) and 2,5‐dimethylfuran (DMF) were explored by regulating the nanosized Pt on Co/Al2O3 catalysts. Characterization results revealed that the catalyst acidity was influenced by adjusting the Co/Pt composition, while the addition of more Pt loading on Co/Al2O3 catalysts resulted in a facilitation of H2 reduction process. Lower size of catalyst particles was obtained for the Co−Pt system in comparison to the monometallic Co/Al2O3 catalyst. Additionally, the structural characterizations by XRD, XANES, and XPS established the co‐existences between metallic Pt0/Co0 and oxophilic PtO2/CoOx, acting as the active components for the reactions. Operated under a full HMF conversion, the Co1Pt0.050Al catalyst with high Pt loading gave >99.9 % BHMF selectivity at 40 °C; whereas, an 86.7 % of DMF selectivity was noticeable over low Pt loading of the Co1Pt0.013Al catalyst at 160 °C. This investigation evidenced that the selective production of BHMF or DMF towards hydro‐conversion of HMF was relied on the amount of Pt contents on Co/Al2O3 catalyst, in which the metal sizes and acidity had meaningful effects on the hydrogenation and hydrogenolysis processes. [ABSTRACT FROM AUTHOR]

The novel bifunctional Ni−Re supported on bimodal SAPO‐11 catalyst was designed for an economically combined process of direct triglycerides hydro‐deoxygenation and isomerization into low‐cold flow diesel. The catalyst with a Ni to Re molar ratio of 1 : 0.12 exhibited superior performance for diesel production containing large fraction of iso‐alkanes in comparison to Ni and Re benchmarks. Comprehensive characterizations revealed that the detection of Ni and Re co‐existed with NiO and ReOx on SAPO‐11 after the reduction confirmed by XRD, XANES, and XPS analysis gave a large distribution of Lewis acid sites (>80 %) noticed by Pyridine‐DRIFTS measurement. Under investigations of WHSV, reaction temperature, and H2 pressure, the NiRe0.12 catalyst contributed a nearly theoretical 77.1 % liquid yield, accompanied by a 18.2 % jet‐range and 52.1 % diesel‐range yields with a classification for 46.8 % iso‐alkanes and 23.5 % normal alkanes yields; whereas, the cold‐flow properties of liquid product were in the ranges of winter diesel standard. It was remarkably noticed that the combination effects of Ni and nanosized Re species substantially improved the diesel production comprising iso‐alkanes components with proper catalyst lifetime and low carbon deposition attributing to the fabricated active metal species on bimodal SAPO‐11 features with large distribution of Lewis acidic sites. [ABSTRACT FROM AUTHOR]

Keywords: Hydrodeoxygenation; Isomerization; NiRe catalyst; Palm oil; Synthetic diesel EN Hydrodeoxygenation Isomerization NiRe catalyst Palm oil Synthetic diesel 1 1 1 10/12/23 20231006 NES 231006 B The Front Cover b illustrates an artwork design for showcasing the developed bifunctional NiRe/SAPO-11 catalyst along with "KHON", the masked dance drama in Thailand. Hydrodeoxygenation, Isomerization, NiRe catalyst, Palm oil, Synthetic diesel Front Cover: Enhancing the Hydrodeoxygenation and Isomerization using Re Nanoparticles Decorated on Ni/SAPO-11 Catalysts for Direct Production of Low-Cold Flow Diesel from Triglycerides (ChemCatChem 19/2023). [Extracted from the article]