Kinetics, carbonization

The overall benefits of this high efficiency combustor over a conventional bubbling- or turbulent-bed regenerator are enhanced and controlled carbon-bum kinetics (carbon on regenerated catalyst at less than 0.05 wt %) ease of start-up and routiae operabiUty uniform radial carbon and temperature profiles limited afterbum ia the upper regenerator section and uniform cyclone temperatures and reduced catalyst iaventory and air-blower horsepower. By 1990, this design was well estabUshed. More than 30 units are ia commercial operation. 

All the oxidants convert primary and secondary alcohols to aldehydes and ketones respectively, albeit with a great range of velocities. Co(III) attacks even tertiary alcohols readily but the other oxidants generally require the presence of a hydrogen atom on the hydroxylated carbon atom. Spectroscopic evidence indicates the formation of complexes between oxidant and substrate in some instances and this is supported by the frequence occurrence of Michaelis-Menten kinetics. Carbon-carbon bond fission occurs in certain cases. 

Most of the normally encountered applications of proton and carbon NMR spectroscopy have been applied in studies of vanadate complexes, complexation reactions, equilibria, and kinetics. Carbon-13 studies of the influence of complexation... 

As mentioned, three types of kinetics are involved in the removal of nitrogen nitrification kinetics, denitrification kinetics, and carbon kinetics. Carbon kinetics refer to the kinetics of the heterotrophic aerobic reactions. By analogy with the nitrification or denitrification kinetics,... 

Kinetic carbon-13 isotope effects in the decarboxylation of 2,4-dihydroxybenzoic acid at 85 °C [247, 249]... 

The main evidence for this cyclic mechanism over an alternative stepwise mechanism lies in the failure of Maruyama et al. to observe any partial reactions catalysed by PEPC. The mechanism is also consistent with the stereochemistry of carboxylation at vinyl carbon determined by Rose et al. (1969). O Leary et a/. (1981) have studied the kinetic (carbon) isotope effect associated with PEPC-catalysed carboxylation of PEP, employing isotopi-cally equilibrated HC03 /C02. Comparison of these KIEs with those for standard C—C bond forming and breaking processes led to the proposal of a stepwise mechanism, involving the intermediacy of carboxyphosphate (Scheme 42b). 

In actual practice, the thermal reaction is often catalyzed by silver salts. Under these conditions, there is no detectable kinetic carbon-isotope effect when the... 

Even gas type pressurizing crystalhzing poly(lactic acid) has influence on crystallization kinetics. Carbon dioxide, because of its solubility in molten polymer, increased... 

Thermodynamically carlxMi is less stable in acid media than, for example, Pt, but due to the slow reaction kinetics, carbon can still be used in fuel cell [143]. Carbon (graphite) can be electrochemically oxidized to CO2 at quite low potentials ... 

Ivers-Tiffee E, Timmermann H, Leonide A, Mentzer NH, Malzbender J (2009) Methane reforming kinetics, carbon deposition, and redox durability of Ni/8 yttria stabilized zirconia (YSZ) anodes. In Vielstich W, Yokokawa H, Gasteiger HA (eds) Handbook of fuel cells fundamental technology and applications vol 6. Advanced in electrocatalysis, materials, diagnostics and durability Part 2. Wiley, Chichester, pp 933-956... 

Kinetically, carbon is oxidized through the following mechanism, expressed by reactions (vii-ix) [57, 58], where the carbon in the lattice structure is oxidized to generate surface oxide, followed by hydrolysis and gasification of oxidized carbon to CO2. The subscript s in reactions (vii-ix) denotes the surface species. 

Marsh H, Martinez-Escandell M, Rodrfguez-Reinoso F. Review Semicokes from pitch pyrolyses mechanisms and kinetics. Carbon 1999 37(3) 363-390. 

Formation.—The lack of a kinetic carbon isotope effect in the formation of MeMgl (3) from Mel in EtaO indicated that the r.d.s. involved radical ion-pair formation [equation (1)], by outer-sphere electron transfer from Mg to Mel (RX) rather than by an inner-sphere electron transfer mechanism in which the C—I bond is cleaved in the r.d.s. [equation (2)]. During the formation of (3) in the weakly basic CHa CHCHaOPh, side-products, Me—Me and CH2=CHCH8CH3,... 

TI Non-Flory product distributions in Fischer - Tropsch synthesis catalyzed by ruthenium, cobalt. and iron KW Fischer Tropsch synthesis hydrocarbon distribution. Flory kinetics carbon monoxide hydrogenation, chain growth carbon monoxide hydrogenation, ruthenium catalyst carbon monoxide hydrogenation, cobalt iron catalyst hydrocarbon distribution IT Hydrocarbons, preparation... 

Lapidus G, Barton D, Yankovich PE (1966b) Reversing the intramolecular kinetic carbon isotope effect in the gas phase decomposition of oxalic acid. J Phys Chem 70 3155-3159... 

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