01921nas a2200289   4500008004100000022001400041245012100055210006900176260000900245300001100254490000800265520098600273653001601259653002601275653001801301653001001319653001401329653001701343653000801360100002101368700001901389700002201408700002601430700002001456700002601476856012901502       2023                        eng d  a2468-823100aNitric acid free cyclohexane to adipic acid production using nickel and vanadium incorporated AlPO-5 molecular sieve0 aNitric acid free cyclohexane to adipic acid production using nic  cAPR   a1130510 v5403 a<p>
	Rationally designing a stable and sustainable metal oxide supported over the molecular sieve catalysts for oxidizing cyclohexane (CYH) to adipic acid (AA) is vital in industrial applications. The in-situ hydrothermal synthesis method successfully incorporated vanadium and nickel into the aluminium phosphate-5 (AlPO-5) molecular sieves (MFI structure). The XPS and NH3 TPD analysis disclosed that the addition of Ni into V-AlPO-5 stabilizes the ratio of V4+/V5+, creating strong acidic sites and the formation of NiOOH, which are a vital role for the selective CYH oxidation to AA. An in-situ DRIFT study reveals that nickel takes part in the formation of dicarboxylate ions as an intermediate to form AA. Our catalytic studies profoundly suggested that the Ni0.1V0.2AlPO-5 catalyst used for CYH oxidation gives better selectivity towards AA (53%) in the presence of oxygen at an appropriate amount of solvent without an initiator or promoter within a short time (3h).</p>
10aAdipic Acid10aCyclohexane oxidation10aIn situ DRIFT10aNiOOH10aNiVAlPO-510aRatios ofV4+10aV5+1 aPrabu, Marimuthu1 aSharma, Shweta1 aRaja, Abhishekram1 aArchana, Ramakrishnan1 aSamruddhi, Mane1 aRaja, Thirumalaiswamy  uhttp://library.ncl.res.in/content/nitric-acid-free-cyclohexane-adipic-acid-production-using-nickel-and-vanadium-incorporated02468nas a2200241   4500008004100000022001400041245013900055210006900194260000900263300001600272490000700288520157200295100002101867700002001888700003701908700002601945700002501971700001901996700003202015700001902047700002602066856013402092       2024                        eng d  a1144-054600aNew insights into the composition and catalytic performance of VOx-Ga/γ-Al2O3 for the oxidative dehydrogenation of propane to propene0 aNew insights into the composition and catalytic performance of V  cAUG   a15077-150870 v483 a<p>
	Oxidative dehydrogenation (ODH) of propane is a promising alternative route for propene production. In this work, we developed a series of vanadium and gallium oxides supported on gamma-Al2O3 catalysts by an incipient wetness impregnation method. Among the employed catalysts, the VGA-2 showed superior catalytic activity, and the catalyst was demonstrated for longevity in ODH of propane with a stable activity using a continuous flow fixed bed reactor at 400 degrees C. H-2-TPR and UV-visible spectra showed the presence of highly dispersed monomeric VOx species with tetrahedral coordination geometry, which influences product selectivity. The characterization results also conferred that the redox nature of vanadium (V5+ and V4+) oxide and higher V5+ content on the surface of the VGA-2 catalysts are more favourable for C-H activation. In addition, the pyridine-FTIR and Ga-71 solid-state NMR studies further substantiated the presence of Lewis acid sites and tetrahedrally coordinated Ga3+Ox species that are highly responsible for the ODHP activity, respectively. Furthermore, in situ-DRIFTS studies conferred that the propane adsorption at ambient temperature showed the formation of intermediate propoxide species with the evolution of sigma-bonds and with further increase in the temperature to 325 degrees C; the stretching vibrations of the =C-H and -C-H bonds in the propylene molecule were observed. The spent catalysts were also analyzed by thermogravimetric analysis, where the optimized catalyst (VGA-2) showed the least coke deposition.</p>
1 aKandasamy, Prabu1 aGawali, Sheetal1 aVenugopalan, Aswathy, Thareparam1 aManikandan, Marimuthu1 aMekala, Siva, Prasad1 aShelke, Ankita1 aAjithkumar, Thalasseril, G.1 aBhatte, Kushal1 aRaja, Thirumalaiswamy  uhttp://library.ncl.res.in/content/new-insights-composition-and-catalytic-performance-vox-ga%CE%B3-al2o3-oxidative-dehydrogenation