F:Flammable;
71-23-8Relevant articles and documents
Hydrogenation catalysts based on platinum- and palladium-containing nanodiamonds
Magdalinova,Kalmykov,Klyuev
, p. 33 - 39 (2014)
Platinum and palladium nanoparticles of 4-5 nm size applied at nanodiamonds have been shown to efficiently catalyze liquid-phase hydrogenation of different organic compounds (nitrocompounds, azomethines, and unsaturated hydrocarbons and alcohols) under mild conditions (T = 318 K, hydrogen pressure of 0.1 MPa, solution in ethanol). Using of palladium on nanodiamond containing 3 wt % of metal has been most efficient.
Hydrogenation of unsaturated compounds in the presence of palladium-containing modified carbon nanofibers
Osipov,Klyuev
, p. 928 - 931 (2013)
Palladium-containing carboxylated carbon nanofibers were studied as catalysts for hydrogenation of double bond >C=C in olefins, unsaturated alcohols, and acids, as well as for hydrogenation of nitroarenes. The developed catalyst is 7 times more efficient than the industrial analog (Pd/C).
Preparation of highly active heterogeneous Au@Pd bimetallic catalyst using plant tannin grafted collagen fiber as the matrix
Ma, Jun,Huang, Xin,Liao, Xuepin,Shi, Bi
, p. 8 - 16 (2013)
Au@Pd bimetallic nanoparticles (NPs) catalysts were synthesized by a seeding growth method using bayberry tannin grafted collagen fiber (BT-CF) as the matrix. In this method, Au3+ was first reductively adsorbed onto BT-CF to form Au NPs, and then they serve as the seeds for the over growth of Pd shell. The morphology of BT-CF-Au@Pd catalyst was observed by TEM and SEM, and the core-shell structure of the Au@Pd was confirmed by EDS and XRD. It was found that the as-prepared BT-CF-Au9@Pd3 catalyst showed excellent synergy effect in liquid-phase hydrogenation of cyclohexene, whose reaction time was three times faster than that catalyzed by BT-CF-Pd catalyst under the same conditions. Meanwhile, the BT-CF-Au9@Pd3 catalyst could be re-used four times without significant loss of activity. In the fourth run, the substrate conversion was still as high as 92.70%, much better than that by using commercial Pd/C catalyst (42.60%). Additionally, BT-CF-Au9@Pd3 catalyst exhibited high hydrogenation activity to various alkenes and nitro-compounds. For example, the TOF of allyl alcohol, styrene and nitrobenzene hydrogenations reached 10,980, 14,732 and 1379 mol mol-1 h-1, respectively.
An Innovative Approach for Highly Selective Direct Conversion of CO2into Propanol using C2H4and H2
Ahlers, Stefan J.,Bentrup, Ursula,Linke, David,Kondratenko, Evgenii V.
, p. 2631 - 2639 (2014)
Multifunctional catalysts are developed for converting CO2with C2H4and H2into propanol. Au nanoparticles (NP) supported on TiO2are found to facilitate this reaction. The activity and selectivity strongly depend on NP size, which can be tuned by the method of Au deposition and by promoting with K. The promoter improves the selectivity to propanol. Under optimized reaction conditions (2 MPa, 473 K, and CO2/H2/C2H4=1:1:1), CO2is continuously converted into propanol with a near-to-100 % selectivity. Catalytic tests as well as mechanistic studies by in situ FTIR and temporal analysis of products with isotopic tracers allow the overall reaction scheme to be determined. Propanol is formed through a sequence of reactions starting with reverse water–gas shift to reduce CO2to CO, which is further consumed in the hydroformylation of ethylene to propanal. The latter is finally hydrogenated to propanol, while propanol hydrogenation to propane is suppressed.
Pd nanoparticles immobilized on boehmite by using tannic acid as structure-directing agent and stabilizer: A high performance catalyst for hydrogenation of olefins
Liu, Jing,Liao, Xuepin,Shi, Bi
, p. 249 - 258 (2014)
Boehmite-supported Pd nanoparticles (Pd-TA-boehmite) were successfully synthesized by a hydrothermal method using tannic acid as the structure-directing agent as well as stabilizer. The physicochemical properties of the Pd-TA-boehmite catalyst were well characterized by XPS, XRD, N 2 adsorption/desorption, and TEM analyses. Catalytic hydrogenation of olefins was used as the probe reaction to evaluate the activity of the Pd-TA-boehmite catalyst. For comparison, the Pd-boehmite catalyst prepared without tannic acid was also employed for olefin hydrogenation. For all the investigated substrates, the Pd-TA-boehmite catalyst exhibited superior catalytic performance than the Pd-boehmite catalyst. For the example of hydrogenation of allyl alcohol, the initial hydrogenation rate and selectivity of the Pd-TA-boehmite catalyst were 23,520 mol/mol h and 99 %, respectively, while those of the Pd-boehmite catalyst were only 14,186 mol/mol h and 93 %, respectively. Additionally, the hydrogenation rate of the Pd-TA-boehmite catalyst could still reach 20,791 mol/mol h at the 7th cycle, which was much higher than that of the Pd-boehmite catalyst (5,250 mol/mol h) at the 4th cycle, thus showing an improved reusability.
Hydrogenation of Propoinaldehyde by Nickel Catalysts Supported on Al2O3, SiO2, TiO2, Ta2O5, and Nb2O5
Funakoshi, Masaki,Inoue, Hakuaki
, p. 1205 - 1208 (1987)
The hydrogenation of propionaldehyde with various nickel catalysts was studied kinetically for a wide range of reaction conditions.The catalysts were supported on Al2O3, SiO2, TiO2, Ta2O5, and Nb2O5.The reaction rates were well correlated with the irreversibly adsorbed hydrogen uptakes.A detailed analysis concluded that this reaction was structure-insensitive under all reaction conditions tested.
Solvent Effects in the Homogeneous Catalytic Reduction of Propionaldehyde with Aluminium Isopropoxide Catalyst: New Insights from PFG NMR and NMR Relaxation Studies
Muhammad, Atika,Di Carmine, Graziano,Forster, Luke,D'Agostino, Carmine
, p. 1101 - 1106 (2020)
Solvent effects in homogeneous catalysis are known to affect catalytic activity. Whilst these effects are often described using qualitative features, such as Kamlet-Taft parameters, experimental tools able to quantify and reveal in more depth such effects have remained unexplored. In this work, PFG NMR diffusion and T1 relaxation measurements have been carried out to probe solvent effects in the homogeneous catalytic reduction of propionaldehyde to 1-propanol in the presence of aluminium isopropoxide catalyst. Using data on diffusion coefficients it was possible to estimate trends in aggregation of different solvents. The results show that solvents with a high hydrogen-bond accepting ability, such as ethers, tend to form larger aggregates, which slow down the molecular dynamics of aldehyde molecules, as also suggested by T1 measurements, and preventing their access to the catalytic sites, which results in the observed decrease of catalytic activity. Conversely, weakly interacting solvents, such as alkanes, do not lead to the formation of such aggregates, hence allowing easy access of the aldehyde molecules to the catalytic sites, resulting in higher catalytic activity. The work reported here is a clear example on how combining traditional catalyst screening in homogeneous catalysis with NMR diffusion and relaxation time measurements can lead to new physico-chemical insights into such systems by providing data able to quantify aggregation phenomena and molecular dynamics.
Highly efficient hydrogenation of methyl propionate to propanol over hydrous zirconia supported ruthenium
Fan, Guangyin,Zhou, Yafen,Fu, Haiyan,Ye, Xiaoli,Li, Ruixiang,Chen, Hua,Li, Xianjun
, p. 229 - 236 (2011)
Hydrous zirconia supported ruthenium catalyst Ru/ZrO2? xH2O, prepared by co-precipitating ruthenium trichloride and zirconium oxychloride with ammonia, was able to catalyze efficiently methyl propionate to propanol under the mild conditions. In aqueous system, the propanol yield of >99% was achieved under the conditions of reaction temperature of 150 °C and hydrogen pressure of 5.0 MPa, while in non-aqueous system the maximum propanol yield was only 47.0%. FTIR spectra and hydrogenation results indicated that the high catalytic performance of Ru/ZrO2?xH2O in aqueous phase results from the cooperation effect between water as a solvent and hydroxyl groups on the surface of carrier.
Palladium-containing nanodiamonds in hydrogenation and hydroamination
Magdalinova,Kalmykov,Klyuev
, p. 299 - 304 (2012)
Palladium catalysts in the form of Pd nanoparticles supported on nanodiamonds have been studied in the hydrogenation of nitrobenzene, allyl alcohol, and cyclohexene and in the hydrogenating amination of propanal with 4-aminobenzoic acid. The ratio of two valence states of palladium, i.e., Pd 2+ and Pd0, in the catalysts has been determined by XPS. The dependence of hydrogenation reaction rate on electron density at the reaction site of nitrobenzene, allyl alcohol, cyclohexene, and 4-(propylideneamino)benzoic acid molecules has been studied using quantum chemical calculations (HF/6-31G, PCM). Pleiades Publishing, Ltd., 2012.
Sulphonated "click" dendrimer-stabilized palladium nanoparticles as highly efficient catalysts for olefin hydrogenation and Suzuki coupling reactions under ambient conditions in aqueous media
Ornelas, Catia,Ruiz, Jaime,Salmon, Lionel,Astruc, Didier
, p. 837 - 845 (2008)
Water-soluble 1,2,3-triazolyl dendrimers were synthesized by "click chemistry" and used to stabilize palladium nanoparticles (PdNPs). These new "click" dendrimer-stabilized nanoparticles (DSN) are highly stable to air and moisture and are catalytically active for olefin hydrogenation and Suzuki coupling reaction, in aqueous media, under ambient conditions using a low amount of palladium (0.01 mol% Pd). Kinetic studies show high catalytic efficiency and high stability for the new "click" DSN in both reactions. The complexation of potassium tetrachloropalladate (K 2PdCl4) to the triazole ligands present in the dendritic structures was monitored by UV/vis and, after reduction, the nanoparticles were characterized by transmission electron microscopy (TEM).
