106-97-8Relevant articles and documents
Reductive dehydration of butanone to butane over Pt/γ-Al 2O3 and HZSM-5
Blass, Samuel D.,Rosenthal, Corey,Bhan, Aditya,Schmidt, Lanny D.
, p. 54 - 57 (2013)
We show that butanone can be reacted to form n-butane in an isothermal reactor containing a 1 wt.% Pt/γ-Al2O3 and an HZSM-5 catalyst (total mass of 12-400 mg, Si/Al = 11.5) below 160 C with up to 99% selectivity and 67% yield. The catalyst loading (12-400 mg) and temperature (100-250 C) were varied to obtain primary products whose selectivities decreased with conversion and secondary/tertiary products whose selectivities increased with conversion. As conversion increased, the selectivities of butanol and butene decreased, showing the formation of butane from butanone through a series reaction pathway: butanone → 2-butanol → butene → butane. Butane selectivity increased as the temperature was increased from 100 to 200 C when compared at similar conversions due to higher dehydration rates over the zeolite. Processing ketones at low temperatures over bifunctional catalysts may be an efficient means of obtaining high yields of stable paraffins from reactive oxygenates.
Deceptive Similarities in the Reactions of Fe+ and Co+ with Linear Nitriles in the Gas Phase
Lebrilla, Carlito B.,Drewello, Thomas,Schwarz, Helmut
, p. 5639 - 5644 (1987)
The gas-phase reactions of the transition-metal ions Fe+ and Co+ with linear C(4)-C(12) nitriles are reported.In spite of an overall similar reactivity pattern, a more detailed analysis, based on the study of labeled nitriles, reveals distinct differences with regard to the mechanisms of elimination of alkenes and alkanes.For both metal ions, hydrogen and alkenes are generated from linear C(4)-C(12) nitriles, and the intermediates are formed via oxidative addition to terminal and internal C-H bonds.For the RCN/Fe+ system insertion in an internal C-H bond commences at position C(8) of the nitrile; for the analogous RCN/Co+ system, the oxidative addition to an internal C-H bond starts at position C(7) of the nitrile.Similarly, alkane formation is different for the two transition-metal ions.For RCN/Fe+ the generation of alkanes is observed for nitriles having at least eight carbon atoms; in contrast, the elimination of alkanes from RCN/Co+ is already observed for C(6) nitriles.Alkane elimination seems to follow the conventional mechanism (i.e., oxidative addition to a C-C bond, β-hydrogen transfer, and reductive elimination) for the RCN/Co+ system, whereas for the RCN/Fe+ complex there exists an additional mechanism.This mechanism corresponds to the loss of H2 from an internal position of the alkyl chain followed by the elimination of an alkene.Some possible origins of the different behavior of Fe+ vs.Co+ are discussed.
Cobalt-Iron-Manganese Catalysts for the Conversion of End-of-Life-Tire-Derived Syngas into Light Terminal Olefins
Falkenhagen, Jan P.,Maisonneuve, Lise,Paalanen, Pasi P.,Coste, Nathalie,Malicki, Nicolas,Weckhuysen, Bert M.
, p. 4597 - 4606 (2018)
Co-Fe-Mn/γ-Al2O3 Fischer–Tropsch synthesis (FTS) catalysts were synthesized, characterized and tested for CO hydrogenation, mimicking end-of-life-tire (ELT)-derived syngas. It was found that an increase of C2-C4 olefin selectivities to 49 % could be reached for 5 wt % Co, 5 wt % Fe, 2.5 wt % Mn/γ-Al2O3 with Na at ambient pressure. Furthermore, by using a 5 wt % Co, 5 wt % Fe, 2.5 wt % Mn, 1.2 wt % Na, 0.03 wt % S/γ-Al2O3 catalyst the selectivity towards the fractions of C5+ and CH4 could be reduced, whereas the selectivity towards the fraction of C4 olefins could be improved to 12.6 % at 10 bar. Moreover, the Na/S ratio influences the ratio of terminal to internal olefins observed as products, that is, a high Na loading prevents the isomerization of primary olefins, which is unwanted if 1,3-butadiene is the target product. Thus, by fine-tuning the addition of promoter elements the volume of waste streams that need to be recycled, treated or upgraded during ELT syngas processing could be reduced. The most promising catalyst (5 wt % Co, 5 wt % Fe, 2.5 wt % Mn, 1.2 wt % Na, 0.03 wt % S/γ-Al2O3) has been investigated using operando transmission X-ray microscopy (TXM) and X-ray diffraction (XRD). It was found that a cobalt-iron alloy was formed, whereas manganese remained in its oxidic phase.
Catalytic: N -pentane conversion on H-ZSM-5 at high pressure
Schreiner, Edward P.,Teketel, Shewangizaw,Lobo, Raul F.
, p. 4245 - 4251 (2016)
The effect of temperature (633-723 K), pressure (10-60 bar) and weight hourly space velocity (WHSV) (400-1500 gC5 gcat-1 h-1) on the conversion of n-pentane on H-[Al]ZSM-5 type catalysts has been investigated. Catalyst properties were tested using a packed-bed laboratory microreactor and reaction products were analyzed via online gas chromatography. 5-25% pentane conversion was observed at a pressure of 40 bar and temperatures in the range of 633-723 K. Reactant consumption rate approached saturation kinetics at pressures above 30 bar (～14% conversion, 673 K). At 40 bar and 673 K, increasing WHSV (400-1500 gC5 gcat-1 h-1) resulted in a reduction in pentane conversion (26-10%). In all cases, propane and butane were the major products, followed by heavier C6+ compounds and other lighter products (C1-C4 paraffins and olefins). Propane carbon selectivity increased from 24% at 633 K to 34% at 723 K, while butane carbon selectivity (～40%) was nearly constant. An inverse relationship between the production of C6+ and light products was observed with changes in reaction conditions. The carbon selectivity to C6+ compounds increased from 20% at 10 bar to 27% at 60 bar and decreased from 28% at 633 K to 18% at 723 K. At all reaction conditions, the observed product distribution can be explained as the result of fast bimolecular reactions, including hydride transfer and alkylation.
Hyrogenation of Carbon Monoxide, Aldehydes, and Unsaturated Hydrocarbons on Titania-Supported Palladium Catalysts
Wu, Jihong,Funakoshi, Masaki,Nagamoto, Hidetoshi,Komiyama, Hiroshi,Inoue, Hakuai
, p. 493 - 498 (1989)
Pd/TiO2 catalysts prepared by different methods showed quite different catalytic activities in the hydrogenation of CO and other unsaturated compouds.The catalyst prepared by coprecipitation od Pd acetate and titanium tetraisopropoxide contained smaller Pd particles than those in catalysts prepared by impregnation methods.In the hydrogenation of CO, activities of the catalysts increased with increase in the Pd dispersion.The coprecipitated catalyst was much more active for this reaction than the other catalysts and showed high activity for methanol formation under normal pressure.In the hydrogenation of propionaldehyde to 1-propanol, the catalysts showed similar behavior to that in the CO/H2 reaction.However, in hydrogenation of C=C double bonds, the activity order of the catalysts was reverse.Higher activity was obtained on the impregnated catalysts with larger Pd particle size and this trend was stronger in hydrogenation of the conjungated butadiene and C=C bond in acrylaldehyde than in the hydrogenation of ethylene.
Role of Ga3+promoter in the direct synthesis of iso-butanolviasyngas over a K-ZnO/ZnCr2O4catalyst
Zhang, Tao,Zeng, Chunyang,Wu, Yingquan,Gong, Nana,Yang, Jiaqian,Yang, Guohui,Tsubaki, Noritatsu,Tan, Yisheng
, p. 1077 - 1088 (2021)
The direct synthesis of iso-butanol is an important reaction in syngas (composed of CO and H2) conversion. K-ZnO/ZnCr2O4(K-ZnCr) is a commonly used catalyst. Here, Ga3+is used as an effective promoter to boost the efficiency of the catalyst and retard the production of CO2. X-ray diffraction, X-ray photoelectron spectroscopy, ultraviolet-visible diffuse reflection spectroscopy and electron microscopy were used to characterize the structural variations with different amounts of Ga3+, the results showed that the particle size of the catalyst decreases with the addition of Ga3+. The temperature-programmed desorption of NH3and CO2, and diffuse reflectance infrared Fourier-transform spectroscopy (DRIFTs) analysis of the CO adsorption revealed that the acidity and basicity were altered owing to the different forms of Ga3+adoption. X-ray photoelectron spectroscopy and density functional theory (DFT) calculations revealed that the formation of Ga clusters that are coordinated on the exposed surfaces of ZnCr2O4, and undergo a tetra-coordinated Ga3+exchange with one of the Zn in ZnCr2O4(ZG) and ZnGa2O4, probably depends on the amount of Ga added. The structural evolution of the Ga3+promoted K-ZnO/ZnCr2O4catalysts can be described as follows: (i) the main forms are ZG and Ga coordinated ZnCr2O4, in which the amount of Ga3+is below 1.10 wt%; and (ii) the Ga3+containing compound is gradually changed from ZG to ZnGa2O4and the amount of gallium clusters increased when the amount of Ga3+was higher than 1.10 wt%. The catalytic performance evaluation results show that K-Ga1.10ZnCr exhibits the highest space time yield and selectivity of alcohols, in which the three compounds play different roles in syngas conversion: ZG is the main active site that boosts the efficiency of the catalysts, owing to the intensified CO adsorption and decreased activation energy of CHO formation through CO hydrogenation; ZnGa2O4only modifies the surface basicity and acidity on the catalyst, thereby impacting the carbon chain growth after the CO is adsorbed. The effects of Ga coordinated with ZnCr2O4shows little impact on the CO adsorption owing to the weak electron donating effects of Ga.
Enzymatic Electrosynthesis of Alkanes by Bioelectrocatalytic Decarbonylation of Fatty Aldehydes
Abdellaoui, Sofiene,Macazo, Florika C.,Cai, Rong,De Lacey, Antonio L.,Pita, Marcos,Minteer, Shelley D.
, p. 2404 - 2408 (2018)
An enzymatic electrosynthesis system was created by combining an aldehyde deformylating oxygenase (ADO) from cyanobacteria that catalyzes the decarbonylation of fatty aldehydes to alkanes and formic acid with an electrochemical interface. This system is able to produce a range of alkanes (octane to propane) from aldehydes and alcohols. The combination of this bioelectrochemical system with a hydrogenase bioanode yields a H2/heptanal enzymatic fuel cell (EFC) able to simultaneously generate electrical energy with a maximum current density of 25 μA cm?2 at 0.6 V and produce hexane with a faradaic efficiency of 24 %.
Influence of Strong Metal-Support Interaction on Exchange with Deuterium and other Reactions of Hydrocarbons. Part 1. - Studies with Rh/TiO2 and Rh/SiO2
Costa Faro, Arnaldo da,Kemball, Charles
, p. 741 - 748 (1995)
The changes in the catalytic properties of Rh/TiO2 caused by raising the reduction temperature from 473 to 773 K have been investigated for four reactions, the exchange with deuterium of methane and cyclopentane, and the hydrogenolysis of 2,2-dimethylpropane and methylcyclopentane.The so-called strong metal-support interaction (SMSI) brought about by the high-temperature reduction had least effect on the exchange of methane but reduced the rate of hydrogenolysis of 2,2-dimethylpropane by factors of 1E4 or 1E5.The SMSI was reversible and its influence on each of the reactions was eliminated by oxidation of the catalyst followed by low-temperature reduction.No marked changes in the catalytic behaviour of Rh/SiO2 resulted from increasing the reduction temperature.The results provide further evidence for the existence of a number of kinds of catalytic sites on Rh/TiO2.The sites for the more structure-sensitive reactions tend to be more seriously affected by SMSI and probably involve more metal atoms than the sites responsible for methane exchange.
Skeletal Rearrangement of Alkanes over Ir/Al2O3. Transformation of n-Pentane, 2-Methylbutane and 2,2-Dimethylbutane
Sarkany, Antal
, p. 1511 - 1522 (1989)
Transformation of n-pentane, 2-methylbutane and 2,2-dimethylbutane has been investigated as a function of the H2/hydrocarbon ratio over a 10 wtpercent Ir/Al2O3 catalyst of 14 percent dispersion.The selectivity of isomer formation has been observed to decrease with the increase of the H2/hydrocarbon ratio and follow the sequence n-pentane > 2-methylbutane >> 2,2-dimethylbutane.The effect of the experimental conditions on the product selectivity has been interpreted considering the actual surface state of the working catalyst.
On the Active Species of Aluminium(III) Bromide-Copper(II) Bromide Mixtures as Catalysts for the Isomerization of Pentane
Kitajima, Nobumasa,Sakuma, Shigeharu,Ono, Yoshio
, p. 1201 - 1205 (1980)
Mixtures of AlBr3 and CuSO4 have high catalytic activity and selectivity for the isomerization of pentane at room temperature.The isomerization obeys the first-order kinetics with respect to pentane and proceeds both in the liquid phase and on the surface of copper(II) sulphate.The complex formed from the two substances seems responsible for the catalytic activity.
