01826nas a2200157 4500008004100000245013500041210006900176260000800245490000800253520117200261100002101433700001901454700003701473700002601510856013201536 2021 eng d00aHighly efficient and reusable Ru-NaY catalyst for the base free oxidation of 5-Hydroxymethylfurfural to 2,5-Furandicarboxylic acid0 aHighly efficient and reusable RuNaY catalyst for the base free o cSEP0 v3753 a

Oxidation of 5-hydroxymethylfurfural (HMF) to 2,5-furandicarboxylic acid (FDCA) is an important reaction for the production of recyclable bio-based polymers. Herein, we report a series of Ru nanoparticles supported on NaY zeolites catalysts for the oxidation of HMF to FDCA. The catalysts were prepared by simple ion exchanged method. Among all the catalysts, the optimized 3 wt % Ru-NaY catalyst showed superior catalytic activity under base free conditions with a shorter period of reaction time. The conversion of HMF was 100 % with 94 % FDCA yield. This catalyst was reused for fourth cycles, with an insignificant decrease in the yield of FDCA. H2-chemisorption and HRTEM studies confirmed that high metal dispersion and small size of Ru nanoparticles play vital roles for the HMF oxidation. In addition, the acidic hydroxyl groups of the supercage as well as higher amount of metallic Ru° are also responsible for the high yield and productivity of FDCA.

1 aKandasamy, Prabu1 aGogoi, Pranjal1 aVenugopalan, Aswathy, Thareparam1 aRaja, Thirumalaiswamy uhttps://library.ncl.res.in/content/highly-efficient-and-reusable-ru-nay-catalyst-base-free-oxidation-5-hydroxymethylfurfural-2502324nas a2200217 4500008004100000022001400041245011700055210006900172260000800241490000700249520155600256653001701812653001301829653002301842653001801865653002501883100002101908700002601929700002301955856012801978 2025 eng d a1867-388000aHydrodeoxygenation of guaiacol to cyclohexanol using noble metal-supported Ni-based perovskite-derived catalysts0 aHydrodeoxygenation of guaiacol to cyclohexanol using noble metal cAUG0 v173 a

This study focuses on the role of noble metal-doped Ni-based perovskites, specifically LaNiO3 and NiTiO3 catalysts in the hydrodeoxygenation (HDO) of guaiacol. The findings demonstrate that reduced Ru-LaNiO3 catalyst achieved superior performance with 100% guaiacol conversion and a 75% selectivity toward cyclohexanol, compared to reduced Ru-NiTiO3, which achieved only 43% conversion and 25% cyclohexanol selectivity under identical conditions (240 degrees C, 30 bar H2, and 4 h). High-resolution transmission electron microscopic (HR-TEM) analysis reveals that LaNiO3-supported catalysts exhibit better metal dispersion and smaller nickel nanoparticle sizes compared to NiTiO3-supported counterparts. X-ray photoelectron spectroscopy (XPS) analysis shows that the reduction of nickel and noble metals is more facile on LaNiO3. Additionally, the O 1s XPS profile for reduced Ru-LaNiO3 indicates a higher proportion of lattice oxygen (OLat similar to 79%) and a lower proportion of oxygen vacancies (OVac similar to 21%) compared to other catalyst systems. The optimized OLat/OVac ratio is shown to be critical for the effective HDO of guaiacol. In situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) demonstrates a high HDO reaction rate using reduced Ru-LaNiO3 than reduced Ru-NiTiO3, with cyclohexanol formation attributed to the keto-enol tautomerization pathway. Overall, this study underscores the critical roles of oxygen vacancies, metal dispersion, and metal-metal oxide interactions in the HDO of guaiacol.

10aCyclohexanol10aGuaiacol10aHydrodeoxygenation10aIn-situ DRIFT10aNi-based perovskites1 aMarimuthu, Prabu1 aRaja, Thirumalaiswamy1 aVinu, Ravikrishnan uhttps://library.ncl.res.in/content/hydrodeoxygenation-guaiacol-cyclohexanol-using-noble-metal-supported-ni-based-perovskite