@article {44528, title = {Mixed bacterial culture mediated direct conversion of bio-glycerol to diols}, journal = {Bioresource Technology}, volume = {250}, year = {2018}, month = {FEB}, pages = {86-93}, abstract = {

Direct and economic transformation of biodiesel derived crude glycerol is gaining more significance. During screening of bacterial cultures Klebsiella pneumoniae and Enterobacter aerogenes were able to convert crude bio-glycerol to 2,3-butanediol (2,3-BDO) and 1,3-propanediol (1,3-PDO), as major compounds, ethanol and acetoin as minor compounds, with a conversion of 69\% and 79\% respectively. Process optimization could achieve maximum conversion at pH 7.0, 37 degrees C, 30-40 g/L glycerol and 1.5 g of inoculum until 120 h. Mixed cultures led to complete glycerol conversion with optimal yield and productivity. An innovative approach of using crude glycerol for sustained growth and tolerance of bacteria as source of carbon and energy makes this study more significant. In addition to this, a mixed culture concept introduced here is expected to make impact in process economics for industrial scale synthesis for direct transformation of glycerol into C3 and specifically, C4 diols.

}, keywords = {1, 2, 3-Butanediol, 3-Propanediol, Bioconversion, Bioglycerol, Mixed culture}, issn = {0960-8524}, doi = {10.1016/j.biortech.2017.11.019}, author = {Parate, Roopa and Mane, Rasika and Dharne, Mahesh and Rode, Chandrashekhar} } @article {46739, title = {Advances in solid catalysts for selective hydrogenolysis of glycerol to 1,3-propanediol}, journal = {Catalysis Reviews-Science and Engineering}, year = {2021}, month = {JAN}, type = {Review}, abstract = {

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.

}, keywords = {1, 3-Propanediol, bifunctional metal-metal oxide catalyst, biomass valorization, Glycerol, Hydrogenolysis}, issn = {0161-4940}, doi = {10.1080/01614940.2020.1794737}, author = {Bhowmik, Susmita 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 {48906, title = {Review on microbial 1, 3-propanediol production: Emerging strategies, key hurdles and attainable solutions to re-establish its commercial interest}, journal = {Industrial Crops and Products}, volume = {209}, year = {2024}, month = {MAR}, type = {Article}, abstract = {

1,3-propanediol (1,3-PDO) is a vital value-added bi-functional compound that has numerous uses in the industrial sector including the polymer, pharmaceutical, food, and cosmetics industries. 1,3-PDO biosynthesis from renewable resources through green methods has received considerable attention. However, technical difficulties such as low product titer, by-product accumulation, and incomplete substrate consumption impede its sustainable production at the industrial scale. Hence, understanding the overall 1,3-PDO process development with integrated knowledge of techno-economics would help to build more production facilities across the world. In this view, the biotechnological production of 1,3-PDO is systematically reviewed briefing the synthesis routes, microbial strains, metabolic pathways, and fermentation modes along with several purification strategies. The present review also summarizes key hurdles in 1,3-PDO production and discusses the attainable solutions to achieve higher product titer. Finally, the economic viability of 1,3-PDO biosynthesis is described based on the existing research.

}, keywords = {3-Propanediol, Fermentation processes, Glycerol, Purification strategies, Techno-economical assessment}, issn = {0926-6690}, doi = {10.1016/j.indcrop.2023.117961}, author = {Nimbalkar, Pranhita R. and Dharne, Mahesh S.} }