504-63-2Relevant articles and documents
Selective Hydrogenolysis of Glycerol to 1,3-Propanediol over Rhenium-Oxide-Modified Iridium Nanoparticles Coating Rutile Titania Support
Liu, Lujie,Asano, Takehiro,Nakagawa, Yoshinao,Tamura, Masazumi,Okumura, Kazu,Tomishige, Keiichi
, p. 10913 - 10930 (2019)
The effect of support in Ir-ReOx catalysts for glycerol hydrogenolysis to 1,3-propanediol was investigated. Rutile TiO2 support showed high activity, even higher than previously reported SiO2 support. Anatase TiO2, C, ZrO2, CeO2, Al2O3, and MgO supports showed very low activity of supported Ir-ReOx pairs. Higher Ir-based 1,3-propanediol productivity of Ir-ReOx/rutile catalyst was obtained at the initial stage even with lower Re/Ir ratio (typical Ir loading amount, 4 wt %, nominal ratio of 0.25; actual ratio of 0.24) without addition of H2SO4 than that of Ir-ReOx/SiO2. The 1,3-propanediol productivity over Ir-ReOx catalysts showed dependency on catalyst compositions (metal loading amount), and the relationship between catalyst structure and activity was further established over Ir-ReOx/rutile. Relatively high Ir loading amount in comparison with small surface area (6 wt %, on 6 m2 g-1 rutile TiO2) showed the highest activity (Ir-based activity). From combined characterization results altogether (TPR, TEM, XPS, XAS, CO adsorption, CO FT-IR) with a kinetics study, the Ir metal particles interacted with the partially oxidized ReOx cluster (average valence of Re: +3) almost totally covering the surface of rutile TiO2 particles, and the active site was the Ir-ReOx interface. Small amounts of Ir species were incompletely reduced; however, such IrOx species as well as rutile TiO2 support were not directly involved in glycerol hydrogenolysis. The role of rutile support was regarded as providing a unique environment for stabilization of uniform and small Ir-ReOx particles with very high surface density on rutile TiO2, which increased the number of active sites per Re amount.
Influence of Pd precursors and Cl addition on performance of Pd-Re catalysts in glycerol hydrogenolysis to propanediols
Li, Yuming,Liu, Huimin,Ma, Lan,He, Dehua
, p. 13 - 20 (2016)
Pd-Re/SBA-15 catalysts with different Pd precursors were prepared by the impregnation method. N2 adsorption-desorption, XRD, H2-TPR, TEM and NH3-TPD were used to characterize the physical and chemical properties of the cat
Aqueous-phase deoxygenation of glycerol to 1,3-propanediol over Pt/WO 3/ZrO2 catalysts in a fixed-bed reactor
Qin, Li-Zhen,Song, Min-Jie,Chen, Chang-Lin
, p. 1466 - 1472 (2010)
Deoxygenation of glycerol in aqueous medium catalyzed by Pt/WO 3/ZrO2 at relatively low temperatures (110-140°C) under hydrogen pressure range from 2 to 5 MPa in a fixed-bed continuous-flow reactor gives 1,3-propanediol (1,3-PDO) and n-propanol (n-PrOH) as the predominant products, indicating high selectivity for deoxygenation of the secondary hydroxyl group over the primary hydroxyl groups of the glycerol. The optimum catalyst was prepared by calcination of WO3/ZrO2 at 700°C and loading of 3.0 wt% Pt with W content of 10 wt%. The effect of reaction temperature, hydrogen pressure and initial water content were evaluated to find the optimum reaction conditions. The glycerol conversion and the yield of 1,3-PDO greatly depended on these factors. At 130°C, 4 MPa and 70.2% conversion, the yield of 1,3-PDO was up to 32.0% (1,3-PDO/1,2-PDO = 17.7). The proposed mechanism for glycerol deoxygenation in aqueous medium over Pt/WO 3/ZrO2 is an ionic pathway involving proton and hydride ion transfer steps.
Pt/Nb-WOx for the chemoselective hydrogenolysis of glycerol to 1,3-propanediol: Nb dopant pacifying the over-reduction of WOx supports
Yang, Man,Zhao, Xiaochen,Ren, Yujing,Wang, Jia,Lei, Nian,Wang, Aiqin,Zhang, Tao
, p. 1027 - 1037 (2018)
Selective hydrogenolysis of glycerol to 1,3-propanediol (1,3-PD) is an important yet challenging method for the transformation of biomass into value-added chemicals due to steric hindrance and unfavorable thermodynamics. In previous studies, chemoselective performances were found demanding and sensitive to H2 pressure. In this regard, we manipulate the chemical/physical characteristics of the catalyst supports via doping Nb into WOx and prepared 1D needle-, 2D flake-, and 3D sphere-stack mesoporous structured Nb-WOx with increased surface acid sites. Moreover, Nb doping can successfully inhibit the over-reduction of active W species during glycerol hydrogenolysis and substantially broaden the optimal H2 pressure from 1 to 5 MPa. When Nb doping is 2%, supported Pt catalysts showed promising performance for the selective hydrogenolysis of glycerol to 1,3-PD over an unprecedentedly wide H2 pressure range, which will guarantee better catalyst stability in the long run, as well as expand their applications to other hydrogen-related reactions.
Discovering positively charged Pt for enhanced hydrogenolysis of glycerol to 1,3-propanediol
Zhao, Binbin,Liang, Yu,Liu, Lei,He, Qian,Dong, Jinxiang
, p. 8254 - 8259 (2020)
Atomically-dispersed Pt supported on WOx-modified tantalum oxide was developed as a highly active catalyst for selective hydrogenolysis of glycerol, with the productivity of 30.80 g gPt-1 h-1 toward 1,3-propanediol. The WOx species pre-deposited on T-Ta2O5 were found to assist the atomic dispersion of platinum. The WOx-stabilized Ptδ+ species adsorb hydrogen easily and facilitate the hydrogen heterolytic dissociation, which significantly enhances the capability of in situ generated Br?nsted acid sites and the hydrogenation activity. This provides a new strategy for developing bi-functional catalysts for a broad range of hydrogen and acid-involved reaction.
Polymerization mechanism of trimethylene carbonate carried out with zinc(II) acetylacetonate monohydrate
Pastusiak, Malgorzata,Dobrzynski, Piotr,Kaczmarczyk, Bozena,Kasperczyk, Janusz
, p. 2504 - 2512 (2011)
The proposed mechanism of initiation and course of ring-opening polymerization of cyclic trimethylene carbonate (TMC) involving zinc(II) acetylacetonate is in accordance with the mechanism of monomer activation. At the first stage of the process, coordination of carbonate to Zn(Acac) 2·H2O complex occurs with the release of weakly coordinated water molecules. This free water molecule reacts with active TMC-Zn(Acac)2 complex. The reaction results in the formation of propanediol and CO2 emission. During further stages of the investigated process, the formed propanediols, or later the oligomeric diols produced with polymerization, are cocatalysts of the chain propagation reaction. The chain propagation occurs because of repeating activation of the TMC monomer through the creation of an active structure resulting in the exchange/transfer reaction between the zinc complex and the monomer, with its following attachment to the hydroxyl groups, carbonate ring opening, and formation of the carbonic unit of polymer chain.
Hydrogenation of 3-hydroxypropanal into 1,3-propanediol over bimetallic Ru-Ni catalyst
Li, Li-Jun,Yi, Wen-Jun,Liu, Tian-Wei,Huang, Chen,Chao, Zi-Sheng
, p. 32027 - 32037 (2017)
A series of Ni-based catalysts, including Ru/SiO2, Ni/SiO2 and Ru-Ni/SiO2, were prepared and employed in the hydrogenation of 3-hydroxypropanal (3-HPA) to 1,3-propanediol (1,3-PDO). The catalysts were systematically characterized by means of XRD, TEM, HRTEM, SEAD, XPS, H2-TPD, H2-TPR and N2-physisorption. It was indicated that the introduction of Ru onto the Ni/SiO2 not only increased the porosity of catalyst and the degree of dispersion of Ni species but also promoted the reduction of Ni2+ to Ni0 and the generation of active hydrogen species. The catalytic performance evaluation showed that the Ru-40Ni/SiO2 catalyst, among all others, could provide the largest yield of 1,3-PDO (above 99.0%) and highest TOF (4.70 × 103 S-1). The optimized reaction conditions over the Ru-40Ni/SiO2 catalyst had been established as follows: reaction temperature = 80 °C, H2 pressure = 2.0 MPa and LHSV = 0.4 h-1. In consideration of its extremely low H2 pressure and very high yield of 1,3-PDO for the hydrogenation of 3-HPA, to the best of our knowledge, the Ru-40Ni/SiO2 catalyst appeared to be the most efficient catalyst among all others reported in the literature. The good performance enabled the Ru-40Ni/SiO2 catalyst to be very promising in its industrial application.
Solid acid co-catalyst for the hydrogenolysis of glycerol to 1,3-propanediol over Ir-ReOx/SiO2
Nakagawa, Yoshinao,Ning, Xuanhe,Amada, Yasushi,Tomishige, Keiichi
, p. 128 - 134 (2012)
Hydrogenolysis of aqueous glycerol was conducted with Ir-ReO x/SiO2 catalyst and solid acid co-catalyst. Considering the reusability and activity, H-ZSM-5 is the most suitable solid co-catalyst. The property of Ir-ReOx/SiO2 + H-ZSM-5 system including kinetics and selectivity trends in various reaction conditions is similar to the case of Ir-ReOx/SiO2 + H2SO4. The catalyst stability, activity, and the maximum yield of 1,3-PrD of Ir-ReO x/SiO2 + H-ZSM-5 were slightly lower than Ir-ReO x/SiO2 + H2SO4. The role of added acid may be to protonate the surface of ReOx cluster to increase the number of hydroxorhenium site, which activates glycerol by the formation of glyceride species.
Nanoparticulate Pt on mesoporous SBA-15 doped with extremely low amount of W as a highly selective catalyst for glycerol hydrogenolysis to 1,3-propanediol
Fan, Yiqiu,Cheng, Shijie,Wang, Hao,Ye, Danhong,Xie, Songhai,Pei, Yan,Hu, Huarong,Hua, Weiming,Li, Zhen Hua,Qiao, Minghua,Zong, Baoning
, p. 2174 - 2183 (2017)
It has been documented that W-modified Pt catalysts with relatively high tungsten contents are effective for the catalytic transformation of biodiesel-derived glycerol to 1,3-propanediol (1,3-PDO). Herein, we report a new finding that Pt/W-SBA-15 catalysts with extremely low W/Si atomic ratios (≤1/80) exhibit excellent catalytic performance in the hydrogenolysis of glycerol to 1,3-PDO. In particular, a Pt/W-SBA-15 catalyst with the W/Si ratio of as low as 1/640 (Pt/W-SBA-15(1/640)) gave rise to the highest 1,3-PDO selectivity of 70.8% at a high glycerol conversion of 86.8% and thus afforded the highest yield of 1,3-PDO of 61.5%. A combination of characterization techniques evidenced that tungsten was homogeneously incorporated into SBA-15 in the form of isolated tetragonal WO4 and only displayed Lewis acidity. The particle size of Pt evolved in a reverse volcanic curve with the W/Si ratio, with the smallest size being observed for Pt/W-SBA-15(1/640). Control experiments indicated strong synergy between Pt nanoparticles (NPs) and WO4 in the hydrogenolysis of glycerol. A probe reaction suggested that Br?nsted acid sites were generated in situ on the Pt/W-SBA-15 catalysts in a H2 atmosphere by the reaction between WO4 and spillover H atoms from the Pt NPs. It is plausible that the hydrided WO4 functioned as a highly selective active centre in the hydrogenolysis of glycerol to 1,3-PDO, whereas the Pt NPs played the role of a reservoir of spillover H atoms. Thus, a good match between the isolated WO4 and the small Pt NPs was responsible for the superior catalytic performance of Pt/W-SBA-15(1/640).
1-Butanol production from glycerol by engineered Klebsiella pneumoniae
Wang, Miaomiao,Fan, Lihai,Tan, Tianwei
, p. 57791 - 57798 (2014)
To utilize the by-product of biodiesel production, Klebsiella pneumoniae, a well-known glycerol-fermenting microorganism, was engineered to produce 1-butanol. The modified CoA-dependent and 2-keto acid pathways were established by expressing the genes ter-bdhB-bdhA and kivd, respectively. The 1-butanol titer and specific BuOH yield were 15.03 mg L-1 and 27.79 mg-BuOH per g cell in KpTBB (K. pneumoniae overexpressing the genes ter-bdhB-bdhA), and 28.7 mg L-1 and 51.58 mg-BuOH per g cell in Kp-kivd (K. pneumoniae overexpressing the gene kivd), respectively. Moreover, the native products in K. pneumoniae fermentation were down regulated using the antisense RNA strategy. The resulting yield of 1,3-propanediol and 2,3-butanediol was reduced by 81% and 15%, respectively. This work reports a new strain, K. pneumoniae, for 1-butanol production and the application of an antisense RNA strategy as an effective method for reducing the main by-products.
