@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 {48187, title = {Insights into active tungsten species on Pt/W/SBA-15 catalysts for selective hydrodeoxygenation of glycerol to 1,3-propanediol}, journal = {Molecular Catalysis}, volume = {531}, year = {2022}, month = {OCT}, pages = {112704}, type = {Article}, abstract = {

Diols are important class of industrial chemicals. Their synthesis from bio-resources (instead from fossil feed-stocks) is sustainable. In this study, we probed active tungsten species on Pt/W/SBA-15 catalysts for selective synthesis of 1,3-propanediol (1,3-PDO) from aqueous glycerol through a liquid-phase hydrodeoxygenation re-action. A synergistic enhancement in glycerol conversion and 1,3-PDO selectivity was observed when both Pt and W were present on the catalyst. A volcano-shape variation followed with a gradual increase in glycerol conversion and 1,3-PDO yield with W-loading (0.25-15 wt\%) was observed. Pt dispersion and acidity of the catalyst dis-played similar variations with the W-loading confirming their critical role in the reaction. Structure-function relationships inferred that oligomeric WOx with moderate Bro center dot nsted acidity (predominant at 1 wt\% W-loading) in contact with dispersed Pt are the active species for 1,3-PDO formation and crystalline WO3 with strong Bro center dot nsted acidity (prevalent above 4 wt\% W-loading) in association with Pt nanoparticles lead to 1-propanol formation.

}, keywords = {3-Propanediol, Active sites, Glycerol, Hydrodeoxygenation, Hydrogenolysis, Supported Pt-WO x}, issn = {2468-8231}, doi = {10.1016/j.mcat.2022.112704}, author = {Bhowmik, Susmita and Enjamuri, Nagasuresh and Sethia, Govind and Akula, Venugopal and Marimuthu, Banu and Darbha, Srinivas} } @article {48789, title = {Promoting effect of titanium on C-O hydrogenolysis of erythritol to 1,4-butanediol over Pt/W/Ti-SBA-15 catalysts}, journal = {Applied Catalysis A-General}, volume = {666}, year = {2023}, month = {SEP }, pages = {119425}, type = {Article}, abstract = {

The C-O hydrogenolysis of erythritol was investigated using Pt/W/Ti-SBA-15 catalysts (4 wt\% Pt, 1 wt\% W and Si/Ti molar ratio = 50, 33, 20 and 10). Ti-incorporation enhanced the hydrogenolysis activity and the yield of 1,4-butanediol (1,4-BDO). A catalyst with Si/Ti = 20 afforded erythritol conversion of 94 mol\% with 1,4-BDO yield of 32.6 mol\% and total BDOs yield of 51.7 mol\% at 190 degrees C, 50 bar H2 and 12 h. For the catalyst with no titanium (Pt/W/SBA-15), a double the time was required to achieve such yield. There observed electronic connectivity amongst Ti, Pt and W. For the catalyst with Si/Ti = 20, a greater amount of interfacial Pt-O-W(Ti) sites with Pt in + 2 oxidation state was present. The enhanced catalytic performance of these catalysts was corresponded to dispersed Pt (that facilitate hydrogen activation and spillover) and acidic interfacial Pt-O-W sites (that promote the adsorption and hydrogenolysis of erythritol to diols).

}, keywords = {Biomass conversion, Erythritol, Hydrogenolysis, Polyols, Promotional effect of Ti, Terminal diol, Ti-SBA-15-supported Pt/W catalysts}, issn = {0926-860X}, doi = {10.1016/j.apcata.2023.119425}, author = {Bhowmik, Susmita and Akula, Venugopal and Sethia, Govind and Marimuthu, Banu and Darbha, Srinivas} }