02081nas a2200205 4500008004100000022001400041245009200055210006900147260000800216520137100224653000601595653001801601653004401619653002501663653001301688653001901701100002101720700002101741856011301762 2021 eng d a0161-494000aAdvances in solid catalysts for selective hydrogenolysis of glycerol to 1,3-propanediol0 aAdvances in solid catalysts for selective hydrogenolysis of glyc cJAN3 a

Glycerol is one of the top 12 platform chemicals obtained from biomass. Its surplus availability as a by-product of biodiesel, fat-splitting and soap manufacturing industries and affordable price lends significant opportunity for its valorization, using solid catalysts, into propanediols (PDOs), particularly to 1,3-propanediol (1,3-PDO), by selective hydrogenolysis. 1,3-PDO is an important chemical with wide applications including that as a precursor in polymers manufacturing. However, the synthesis of 1,3-PDO by selective cleavage of the secondary C-O bond of glycerol in the presence of hydrogen (instead of the primary C-O bond yielding 1,2-PDO) is highly challenging. Of late, supported Pt and Ir catalysts in combination with a reducible oxide (WO(x)or ReOx) were found selective for 1,3-PDO formation. Support, metals composition and additives (co-added metals) affect the performance of these catalysts. Detailed investigations revealed that metal dispersion, electronic connectivity between metal and metal oxide/support, hydrogen activation/spillover and Bronsted acidity are some parameters that influence the activity and selectivity of these bi-functional, metal-metal oxide catalysts. This review summarizes the latest advances in these solid catalysts for selective hydrogenolysis of glycerol to 1,3-PDO, a monomer for advanced polymers.

10a110a3-Propanediol10abifunctional metal-metal oxide catalyst10abiomass valorization10aGlycerol10aHydrogenolysis1 aBhowmik, Susmita1 aDarbha, Srinivas uhttps://library.ncl.res.in/content/advances-solid-catalysts-selective-hydrogenolysis-glycerol-13-propanediol01642nas a2200169 4500008004100000022001400041245012600055210006900181260000800250300001400258490000700272520099600279100002101275700002501296700002101321856013001342 2021 eng d a1144-054600aHydrogenolysis of glycerol in an aqueous medium over Pt/WO3/zirconium phosphate catalysts studied by H-1 NMR spectroscopy0 aHydrogenolysis of glycerol in an aqueous medium over PtWO3zircon cMAR a5013-50220 v453 a

Bifunctional Pt/WO3/zirconium phosphate catalyzes the liquid-phase hydrogenolysis of glycerol in an aqueous medium. H-1 NMR spectroscopy (solvent suppression pulse program) is employed to monitor this reaction. Propanediols (1,3 + 1,2-PDO) formed as the major product along with propanols (1- and 2-POs) as the minor product. A synergistic enhancement in glycerol conversion and selectivity to 1,3-PDO was observed when both Pt and WO3 were present in the catalyst. A volcano-shape variation of catalytic activity with W content was observed. A catalyst with 8 wt% W and 1 wt% Pt exhibited the highest selective hydrogenolysis performance (glycerol conversion = 92.3% and total PDOs selectivity = 45.9% and 1,3-PDO selectivity = 20.8% at 200 degrees C). Dispersed Pt in contact with polytungstate-type WO3 species was found to be the active catalytic site. H-1 NMR spectroscopy is demonstrated as an attractive technique to quantify the products of a glycerol hydrogenolysis reaction.

1 aBhowmik, Susmita1 aEnjamuri, Nagasuresh1 aDarbha, Srinivas uhttps://library.ncl.res.in/content/hydrogenolysis-glycerol-aqueous-medium-over-ptwo3zirconium-phosphate-catalysts-studied-h-101669nas a2200253 4500008004100000245009700041210006900138260000800207300000900215490000700224520088900231653000901120653001501129653001301144653002301157653000701180653001101187653000601198100002101204700002501225700002001250700002101270856012401291 2022 eng d00aC-O hydrogenolysis of C3-C4 polyols selectively to terminal diols over Pt/W/SBA-15 catalysts0 aCO hydrogenolysis of C3C4 polyols selectively to terminal diols  cSEP a10700 v123 a

Pt/W/SBA-15 catalysts (with Pt-loading = 0.5-4 wt% and W-loading = 1 wt%) prepared by the sequential impregnation method were evaluated for selective C-O cleavage of erythritol and glycerol in an aqueous medium. The Pt and W particles dispersed on SBA-15 approached close proximity at higher Pt loadings and afforded synergistic enhancement in C-O hydrogenolysis activity/selectivity. 1,4-Butanediol yields of 30.9% (at 190 degrees C, 50 bar H-2 and 24 h) and 1,3-propanediol yields of 34.4% (at 190 degrees C, 50 bar H-2 and 12 h of reaction) were obtained over these catalysts. Pt nanoparticles (facilitating dissociative H-2 adsorption and spillover) and W (present as acidic oligomeric WOx species; activating and coordinating the polyol via 1 degrees-OH group) worked in tandem for the selective hydrogenolysis of polyols yielding terminal diols of industrial demand.

10adiol10aErythritol10aGlycerol10aHydrodeoxygenation10aPt10aSBA-1510aW1 aBhowmik, Susmita1 aEnjamuri, Nagasuresh1 aMarimuthu, Banu1 aDarbha, Srinivas uhttps://library.ncl.res.in/content/c-o-hydrogenolysis-c3-c4-polyols-selectively-terminal-diols-over-ptwsba-15-catalysts02074nas a2200277 4500008004100000022001400041245013100055210006900186260000800255300001100263490000800274520114500282653001801427653001701445653001301462653002301475653001901498653002201517100002101539700002501560700001901585700002101604700002001625700002101645856013001666 2022 eng d a2468-823100aInsights into active tungsten species on Pt/W/SBA-15 catalysts for selective hydrodeoxygenation of glycerol to 1,3-propanediol0 aInsights into active tungsten species on PtWSBA15 catalysts for  cOCT a1127040 v5313 a

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.

10a3-Propanediol10aActive sites10aGlycerol10aHydrodeoxygenation10aHydrogenolysis10aSupported Pt-WO x1 aBhowmik, Susmita1 aEnjamuri, Nagasuresh1 aSethia, Govind1 aAkula, Venugopal1 aMarimuthu, Banu1 aDarbha, Srinivas uhttps://library.ncl.res.in/content/insights-active-tungsten-species-ptwsba-15-catalysts-selective-hydrodeoxygenation-glycerol01904nas a2200277 4500008004100000022001400041245011700055210006900172260000900241300001100250490000800261520097300269653002301242653001501265653001901280653001201299653002901311653001801340653003901358100002101397700002101418700001901439700002001458700002101478856012701499 2023 eng d a0926-860X00aPromoting effect of titanium on C-O hydrogenolysis of erythritol to 1,4-butanediol over Pt/W/Ti-SBA-15 catalysts0 aPromoting effect of titanium on CO hydrogenolysis of erythritol  cSEP  a1194250 v6663 a

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).

10aBiomass conversion10aErythritol10aHydrogenolysis10aPolyols10aPromotional effect of Ti10aTerminal diol10aTi-SBA-15-supported Pt/W catalysts1 aBhowmik, Susmita1 aAkula, Venugopal1 aSethia, Govind1 aMarimuthu, Banu1 aDarbha, Srinivas uhttps://library.ncl.res.in/content/promoting-effect-titanium-c-o-hydrogenolysis-erythritol-14-butanediol-over-ptwti-sba-15