@article {46897, title = {Solid catalysts for conversion of furfural and its derivatives to alkanediols}, journal = {Catalysis Reviews-Science and Engineering}, volume = {62}, year = {2020}, month = {OCT }, pages = {566-606}, type = {Review}, abstract = {

Alkanediols with five and six carbon atoms (1,2- \& 1,5-pentanediols and 1,2- \& 1,6-hexanediols, respectively) are an important class of industrial chemicals having wide application. Their production from lignocellulosic biomass-derived furfural and its derivatives using solid catalysts is a sustainable and attractive approach. Several bifunctional catalysts with metal (for hydrogenation/hydrogenolysis) and acid/base (for ring opening) functionalities have been reported. Effective and selective conversion of furfurals to a desired diol is still a challenge. This review discusses the recent advances in catalyst development for pentane- and hexanediols. The reaction pathways, active sites, and possible reaction mechanisms over the solid catalysts are discussed. A comparative catalytic activity data of the known catalysts are reported.

}, keywords = {5-hydroxymethylfurfural (HMF), Alkanediol, furfural (FAL), hexanediol, pentanediol, solid catalyst}, issn = {0161-4940}, doi = {10.1080/01614940.2020.1744327, Early Access Date = APR 2020}, author = {Enjamuri, Nagasuresh and Darbha, Srinivas} } @article {47424, title = {Hydrogenolysis of glycerol in an aqueous medium over Pt/WO3/zirconium phosphate catalysts studied by H-1 NMR spectroscopy}, journal = {New Journal of Chemistry}, volume = {45}, year = {2021}, month = {MAR}, pages = {5013-5022}, type = {Article}, abstract = {

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.

}, issn = {1144-0546}, doi = {10.1039/d0nj05557c}, author = {Bhowmik, Susmita and Enjamuri, Nagasuresh and Darbha, Srinivas} } @article {48020, title = {C-O hydrogenolysis of C3-C4 polyols selectively to terminal diols over Pt/W/SBA-15 catalysts}, journal = {Catalysts}, volume = {12}, year = {2022}, month = {SEP}, pages = {1070}, type = {Article}, abstract = {

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.

}, keywords = {diol, Erythritol, Glycerol, Hydrodeoxygenation, Pt, SBA-15, W}, doi = {10.3390/catal12091070}, author = {Bhowmik, Susmita and Enjamuri, Nagasuresh and Marimuthu, Banu 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 {49632, title = {Advances in catalytic conversion of lignocellulosic biomass to ethylene glycol}, journal = {Catalysis Reviews-Science and Engineering}, volume = {66}, year = {2024}, month = {OCT }, pages = {1137-1207}, type = {Review}, abstract = {

Ethylene glycol (EG) is an industrial chemical with multiple applications in polymers, anti-freeze agents, coolants, desiccants and de-icing fluids. It is prepared mainly from fossil feedstock resources. However, its manufacture from renewable sources like lignocellulosic biomass is attractive from the view points of carbon-neutrality and environmental benefits. A few industries have already ventured or committed to produce biomass-derived EG (bio-EG) on a pilot to demonstration scale. At present bio-EG is more expensive than the EG made from fossil resources. Advances are happening in developing more efficient and selective catalysts for the direct conversion of raw biomass and its hydrolysis products (cellulose and glucose) into bio-EG. This review presents the recent advances in catalysts for producing bio-EG.

}, keywords = {2-diol, biomass to chemicals, ethane-1, Hydrogenolysis, Lignocellulose, Monoethylene glycol, solid catalyst}, issn = {0161-4940}, doi = {10.1080/01614940.2022.2111070}, author = {Enjamuri, Nagasuresh and Darbha, Srinivas} }