@article {43966, title = {Selective and reusable Pt-WO x /Al 2 O 3 catalyst for deoxygenation of fatty acids and their esters to diesel-range hydrocarbons}, journal = {Catalysis Today}, volume = {309}, year = {2017}, month = {JUN}, pages = {219-226}, type = {Article}, abstract = {Tungsten oxide promoted platinum catalysts (Pt-WOx/Al2O3) of varying composition were prepared by wet impregnation method and reduced in hydrogen atmosphere. X-ray powder diffraction and photoelectron spectroscopy revealed that Pt is completely reduced to metallic state while tungsten is in +6 and +5 oxidation state. Pt crystallite and particle sizes increased (from 1.2 to 1.4 nm and 2.5 to 3 nm, respectively) in presence of WOx (CO-chemisorption and transmission electron microscopy). Tungsten addition augmented strong acid sites. It enhanced significantly the catalytic activity of Pt/Al2O3 in deoxygenation of fatty acids and their methyl esters. Tungsten altered the reaction pathway from decarbonylation/decarboxylation to hydrodeoxygenation. A catalyst with 4 wt\% Pt and 8 wt\% W exhibited high catalytic performance. Complete conversion of oleic acid and octadecane product selectivity in the range 67.1 - 80.8\% was obtained. Pt-WOx/Al2O3 is a stable and reusable fatty acid deoxygenation catalyst.}, keywords = {biofuels, Deoxygenation, Diesel-range hydrocarbons, Fatty acids, Pt catalyst}, issn = {0920-5861}, doi = {10.1016/j.cattod.2017.06.030}, author = {Janampelli, Sagar and Srinivas, Darbha} } @article {47007, title = {Selective, bifunctional Cu-WOx/Al2O3 catalyst for hydrodeoxygenation of fatty acids}, journal = {Catalysis Science \& Technology}, volume = {10}, year = {2020}, month = {JAN }, pages = {268-277}, type = {Article}, abstract = {

Selective hydrodeoxygenation of oleic acid (OA; in a batch reactor, at 300 degrees C, 30 bar H-2 pressure, reaction time of 1 h and reactant-to-catalyst weight ratio of 2 g OA/0.2 g) forming n-octadecane in yields as high as 93\% over a non-noble metal, sulfur-free, bimetallic Cu-WOx/Al2O3 catalyst is reported for the first time. Several Cu-WOx/Al2O3 compositions were prepared by a sequential wet-impregnation method and evaluated. A catalyst with 10 wt\% Cu and 4 wt\% W enabled the highest activity and selectivity. Upon adding WOx, the amount of moderate and strong acid sites increased and more Cu in the catalyst was in reduced electron-rich metallic (Cu-0) state. The crystallite size and dispersion of Cu were little affected. WOx promoted the fatty acid hydrodeoxygenation activity of Cu. While a monometallic Cu catalyst (10Cu/Al2O3) yielded n-octadecane and n-heptadecane along with high amounts of intermediate octadecanol and octadecanal products, the bimetallic catalyst (10Cu-4WO(x)/Al2O3) gave mainly n-octadecane. Acidity and the high amount of reduced Cu-0 species are responsible for the high catalytic hydrodeoxygenation performance of this bimetallic catalyst.

}, issn = {2044-4753}, doi = {10.1039/c9cy01939a}, author = {Janampelli, Sagar and Sethia, Govind and Darbha, Srinivas} } @article {47309, title = {Selective deoxygenation of fatty acids to fuel-range hydrocarbons over Pt-MOx/ZrO2 (M = Mo and W) catalysts}, journal = {Catalysis Today}, volume = {375}, year = {2021}, month = {SEP}, pages = {174-180}, type = {Article}, abstract = {

A comparative catalytic activity study of Pt-MoOx/ZrO2\ and Pt-WOx/ZrO2\ for deoxygenation of oleic acid (OA) forming fuel-range, linear hydrocarbons is reported. These catalysts (with 4 wt\% Pt and 8 wt\% Mo or W) were prepared by a sequential wet-impregnation method and characterized for the structural and electronic properties. Pt-MoOx/ZrO2\ showed higher catalytic activity than Pt-WOx/ZrO2. Hydrodeoxygenation was the selective pathway over these bifunctional catalysts yielding n-octadecane. High conversion of OA was achieved at 200 {\textdegree}C itself. On the contrary, monometallic Pt/ZrO2\ was weakly active. It was selective mainly toward decarboxylation/decarbonylation producing n-heptadecane. Higher amounts of Pt and metal oxide in reduced forms are responsible for the high hydrodeoxygenation activity and selectivity of these reusable, bimetallic catalysts.

}, doi = {10.1016/j.cattod.2020.04.020}, author = {Janampelli, Sagar and Darbha, Srinivas} }