Kinetics carbon removal

Oxidation kinetics, 292-293 Reduction kinetics, 288 Removal from solution, 443-445 pe-pH diagram, 256,441 Manganese carbonate, 59,433 Manganese oxides, 131 Methane, 257-258, 324 Mica, 102-108 Layer charge, 113 Structure, 115 Molecular Weight, 13,14 Mole fraction, 202 Equivalent fraction, 202 Montmorillonite., 102,104, 109, 123 C-axis spacings, 171 Layer charge, 120 Structure, 171 Composition, 104 Physical properties, 123-124 Chemical properties, 123-124 Muscovite, 104, 123 Structure, 108 Composition, 104... 

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,... 

Wisniewski C, Cruz AL, and Grasmick A. Kinetics of organic carbon removal by a mixed culture in a membrane bioreactor. Biochem Eng J. 1999 3 61-69. 

The kinetics of removal of both organic matter and nitrogen compounds in such a bioactive adsorber with fixed-bed and biofilm on the activated carbon surface is described by an equation for biofiltration [27 ] ... 

Such thermodynamic conclusions are only relevant when the system is completely at equilibrium for reactions (4), (5), and, say, (9), but in an open system, such as a catalyst zone in a reformer where the gas is not yet at equilibrium, reaction between the components of that non-equilibrated gas can produce carbon even when the equilibrated gas shows no affinity for carbon formation. This is particularly so when higher hydrocarbons are involved and reaction (7) is possible. Whether carbon is deposited in that zone depends upon the kinetics of the carbon-forming and carbon-removing reactions, which can be influenced... 

The decomposition of pure phase carbonate minerals has been extensively studied and reviewed (17). The influence of these minerals on oil shale pyrolysis kinetics has not been extensively studied, but the studies of Jukkola et al. (18) and Campbell (15) are notable. The results of both these studies indicate that the major calcite decomposition step is through reaction with silicate minerals in shale to produce Ca- and Ca-, Mg-silicates. The observed enhancement in pyrolysis yield after carbonate removal may be indicative of the catalytic role of silicate minerals in paraffinic and aromatic compound decompositions. In effect, an apparent preference for calcite-silicate interactions in raw shale limits silicate-catalyzed organic reactions which would presumably result in enhanced oil yields. It should be noted, however, that the silicate/carbonate ratio is increasing with net pyrolysis yield for the raw shales, Table I. This may reflect excess silicates becoming free to catalyze organic decomposition. 

Carbon removal by the reverse of reactions 6, 7 and 8 is possible, and operating conditions are generally adjusted to ensure that the feed and product gas compositions are far from values that, thermodynamically, would favour carbon formation (critical carbon limit) [1]. However, the approach to equilibrium is kinetical 1y controlled and, depending on the feed and on local conditions in the reactor, coke formation can and does occur [1,3,4]. 

Respirometric techniques have been extensively used for the determination of BOD and biokinetic parameters. A recent development is the use of this technique for the respiration inhibition kinetics analysis to quantify the toxic (or inhibitory) effect of xenobiotic compounds on the biogenic-carbon removal in biological wastewater treatment systems. 

These rate equations describe the kinetics and mechanisms of the gasification reactions of carbons by carbon dioxide and steam. As such, they describe the processes of activation by carbon dioxide and steam giving insights into mechanisms of carbon removal (the activation process), together with differences between activations by different agents and the effects of inhibition by product gases. 

There are several advantages associated with the MCFC system. First, the high operating temperature dramatically improves reaction kinetics and removes the need for a noble metal catalyst. The higher temperature also makes the cell less prone to carbon monoxide poisoning than lower... 

Except as an index of respiration, carbon dioxide is seldom considered in fermentations but plays important roles. Its participation in carbonate equilibria affects pH removal of carbon dioxide by photosynthesis can force the pH above 10 in dense, well-illuminated algal cultures. Several biochemical reactions involve carbon dioxide, so their kinetics and equilibrium concentrations are dependent on gas concentrations, and metabolic rates of associated reactions may also change. Attempts to increase oxygen transfer rates by elevating pressure to get more driving force sometimes encounter poor process performance that might oe attributed to excessive dissolved carbon dioxide. 

Moehida, I., Kuroda, K., Kawano, S., Matsumura, Y. and Yoshikawa, M., Kinetic study of the continuous removal of SO, on polyacrylonitrilc-bascd activated carbon fibres. 1. Catalytic activity of PAN ACF heat treated at 800 °C,Fuel, 1997, 76(6), 533 536. 

Metal carbonate decompositions proceed to completion in one or more stages which are generally both endothermic and reversible. Kinetic behaviour is sensitive to the pressure and composition of the prevailing atmosphere and, in particular, to the availability and ease of removal of C02. The structure and porosity of the solid product and its relationship with the reactant phase controls the rate of escape of volatile product by inter-and/or intragranular diffusion, so that rapid and effectively complete withdrawal of C02 from the interface may be difficult to achieve experimentally. Similar features have been described for the removal of water from crystalline hydrates and attention has been drawn to comparable aspects of reactions of both types in Garner s review [ 64 ]. 

The kinetics of desulphonation of sulphonic acid derivatives of m-cresol, mesitylene, phenol, p-cresol, and p-nitrodiphenylamine by hydrochloric or sulphuric acids in 90 % acetic acid were investigated by Baddeley et a/.701, who reported (without giving any details) that rates were independent of the concentration of sulphuric acid and nature of the catalysing anion, and only proportional to the hydrogen ion concentration. The former observation can only be accounted for if the increased concentration of sulphonic acid anion is compensated by removal of protons from the medium to form the undissociated acid this result implies, therefore, that reaction takes place on the anion and the mechanism was envisaged as rapid protonation of the anion (at ring carbon) followed by a rate-determining reaction with a base. 

Ethylene is selectively oxidized to ethylene oxide using a silver-based catalyst in a fixed-bed reactor. Ethylene and oxygen are supplied from the gas phase and ethylene oxide is removed by it. The catalyst is stationary. Undesired, kinetically determined by-products include carbon monoxide and water. Ideally, a pure reactant is converted to one product with no by-products. 

The reactivities of pure NaHCOa solid. Sorb NHR, NHR5, and NX30 sorbents were examined in a fast fluidized bed reactor. The CO2 removal of the pure NaHCOa solid increased from 3 % to 25 % when the variables were altered. Removal increased as gas velocity was decreased, as the carbonation temperature was decreased, or as the solid circulation rate was increased. The CO2 removal of Sorb NHR and NHR5 was initially maintained at 100 % for a short period of time but quickly dropped to a 10 to 20 % removal. However, the Sorb NX30 sorbent showed fast kinetics in the fast fluidized reactor, capturing all of the 10 % of the CO2 in the flue gas within 3 seconds in the fast fluidized reactor. 

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