Oxidation n-heptane

TJ. Held, A.J. Marchese, and F.L. Dryer. A Semi-Empirical Reaction Mechanism for n-Heptane Oxidation and Pyrolysis. Combust. Sci. Techn., 123 107-146,1997. 

E. Ranzi, P. Gaffuri, T. Faravelli, and P. Dagaut. A Wide-Range Modeling Study of n-Heptane Oxidation. Combust. Flame, 103 91-106,1995. 

PEAK CYCLE TEMPERATURE, °C Figure 8. Effect of tetraethyllead on n-heptane oxidation... 

Although studies have emerged from a number of different research groups, there are fewer examples of the validation of kinetic models for higher alkanes at present. Minetti et al. [101] have adapted a kinetic model developed by Warnatz to represent n-heptane oxidation. It comprises 168 species in 904 reversible reactions. There is a strong emphasis on the... 

Although the data of Layng and Youker4 were obtained in a bulb type of apparatus, they show the progressively increasing rate of oxidation of n-heptane, heptaldehyde, and heptoic add and the stability of n-heptyl alcohol to oxidation (Fig. 32). No alcohol was found in the products from n-heptane oxidation. 

CURRAN H.J., GAFFURI P., PITZ W.J., WESTBROOK C.K., A comprehensive modeling study of n-heptane oxidation. Combustion and Flame, 114. 149 (1998). 

One result of the reaction lumping above is the removal of the highly reactive species D. This means that a fast timescale was removed from the system, and the stiffness of the corresponding ODE system was decreased. The calculation of lifetimes of species is discussed in Sect. 6.2. Reaction lumping based on timescales may remove species and decrease stiffness, and thus may lead to increases in simulation speed. For example, its application was successful for the further reduction of a skeletal scheme describing n-heptane oxidation in Peters et al. (2002). This will be discussed more fully in connection with the application of the QSSA in Sect. 7.8.6. 

Ahmed, S.S., MauB, F., Moreacz, G., Zeuch, T. A comprehensive and compact n-heptane oxidation model derived using chemical lumping. PCCP 9, 1107-1126 (2007)... 

Davis, S.G. and Law, C.K., Laminar flame speeds and oxidation kinetics of zso-octane-air and n-heptane-air flames, Proc. Combust. Inst., T1,521,1998. 

This paper is concerned with the synthesis of Y zeolite with Si02/Al203 ratio of 4.5 from kaolin taken in Yen Bai-Vietnam and their catal3dic activity for the cracking of n-heptane. The synthesized sample (NaYl) showed the Y zeolite crystallinity of 53% and PI zeolite crystallinity of 32%, and exhibited good thermal stability up to 880 C. The activity and the stability of HYl turned out to be lower than those of standard sample (HYs), but the toluene selectivity was higher. The conversion of n-heptane to toluene might be due to the metal oxide impurities, which was present in the raw materials and this indicates the potential application of this zeolite for the conversion of n-parafRn to aromatics. 

Chromium zeolites are recognised to possess, at least at the laboratory scale, notable catalytic properties like in ethylene polymerization, oxidation of hydrocarbons, cracking of cumene, disproportionation of n-heptane, and thermolysis of H20 [ 1 ]. Several factors may have an effect on the catalytic activity of the chromium catalysts, such as the oxidation state, the structure (amorphous or crystalline, mono/di-chromate or polychromates, oxides, etc.) and the interaction of the chromium species with the support which depends essentially on the catalysts preparation method. They are ruled principally by several parameters such as the metal loading, the support characteristics, and the nature of the post-treatment (calcination, reduction, etc.). The nature of metal precursor is a parameter which can affect the predominance of chromium species in zeolite. In the case of solid-state exchange, the exchange process initially takes place at the solid- solid interface between the precursor salt and zeolite grains, and the success of the exchange depends on the type of interactions developed [2]. The aim of this work is to study the effect of the chromium precursor on the physicochemical properties of chromium loaded ZSM-5 catalysts and their catalytic performance in ethylene ammoxidation to acetonitrile. 

Fe2 + /02 Air oxidation much faster in Aerosol-OT reverse micelles in cyclohexane and n-heptane than in H20 Inouye et al., 1982... 

This section presents the result of the catalytic performances in the case of phenylacetylene hydrogenation reaction. The catalytic evaluation was performed in a classical well-stirred stainless steel reactor operating in batch mode under constant H2 pressure (10 bar) at 17°C using n-heptane as the solvent. As mentioned in Section 13.2.2, no modification of the particle size distribution has been observed by transmission electron microscopy before or after reduction of colloidal oxide particles. 

Stepped surfaces withstand cyclic oxidation-reduction treatments (146) like [111] and some other low-index planes. Steps have either [311] or [110] structures. They are claimed to be the only places where orbital hybridization does not take place (136). No wonder that such platinum (138) and iridium (147) surfaces have enhanced activity in Cg dehydrocyclization of n-heptane. 

More drastic conditions of temperature, pressure and time gave carbon as the product from both aromatic and aliphatic compounds. This carbon is an activated char with decolorizing properties. Tars, tarry substances, the oxides of carbon, and the usual products of the oxidation of aromatic compounds (dicarboxylic acids) were all conspicuous by their absence. Benzotrifluoride oxidized to benzoyl fluoride. The aliphatic compounds cyclohexane, methycyclohexane, n-heptane, etc., could be oxidized to carbon and water. 

W3 (0) j ] were used, as ("Bu N) salts, as complex/aq. Na(lO )7DCE/60°C to effect oxidative cleavage of styrene to benzaldehyde and benzoic acid. Kinetic studies and activation parameters were determined [707]. The system a-( Hx N)j[Ru Si(H30)W,(0)3, ] /TBHP/C H oxidised cyclohexane, n-heptane, n-decane and ethylbenzene to alcohols and ketones [708]. 

The exchange of a number of compounds in this category with deuterium has been examined by Burwell and his colleagues. n-Heptane has been exchanged over nickel-keiselguhr (43), reduced nickel oxide (29), a series of nickel catalysts of varying crystallite size (37), and over palladium supported on 7-alumina (43). Less extensive studies were also made with 2,3-dimethylbutane (29, 43) and n-hexane (42). 

G.M. Come, V. Warth, P.A. Glaude, R. Foumet, F. Battin-Leclerc, and G. Scacchi. Computer-Aided Design of Gas-Phase Oxidation Mechanisms—Application to the Modeling of n-Heptane and Iso-Octane Oxidation. Proc. Combust. Inst., 26 755-762,1996. 

To the Co complex (1.28 g, 2.32 mmol) in heptane (23 mL, purged with carbon monoxide for 3 h before use) was added tri-n-butylphosphine oxide (506 mg, 2.32 mmol). The solution was sealed in a screw-cap resealable tub under an atmosphere of CO and heated to 85°C (over glyme heated at reflux) for 71 h. After cooling, the solution was applied directly to a bed of Fluorisil and eluted with ethyl acetate-petroleum ether 95 5 to 50 50) giving the tricyclic enone 304 mg, 45%) as a colorless oil [a]D 22 +116° (c 2.47, CHC13). 

Oxidation of saturated hydrocarbons. Although the initial oxidation step is chemically difficult, the tissues of our bodies are able to metabolize saturated hydrocarbons such as n-heptane slowly, and some microorganisms oxidize straight-chain hydrocarbons rapidly.30 31 Strains of Pseudomonas and of the yeast Candida have been used to convert petroleum into... 

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