Reaction kinetics 26 INDEX

RCM. See Ring-closing metathesis (RCM) Reaction by-products, removing, 83 Reaction extrusion, 204 Reaction index, 237 Reaction injection molding (RIM), 205 Reaction-in-mold (RIM) nylon, 149 Reaction kinetics, 76, 77 Reaction mechanisms, polyesterification, 66-69... 

Metal Ion Catalyzed Autoxidation Reactions Kinetics and Mechanisms Istvdn Fabian and Viktor Csordds INDEX... 

Index Entries Alcoholysis vegetable oils lipases reaction kinetics biodiesel. 

Index Entries Reaction kinetics glucose decomposition dilute acid hydrolysis kinetic modeling acid-soluble lignin acid-base catalysis rules. 

The performance indexes, which define an optimal catalyst distribution, include effectiveness, selectivity, yield and deactivation rate. The key parameters, affecting the choice of the optimal catalyst profile, are the reaction kinetics, the transport resistances, and the production cost of the catalyst. An extensive review of the theoretical and experimental developments in this area is available [20]. Two typical examples to demonstrate the importance of an appropriate distribution of the active components are now described. 

It needs to be stated clearly that the conditions of saturation thus calculated in the process of water analyses are determined exclusively on the basis of the prevalent analytical data and the employed data available on equilibria. A mineral shown to be supersaturated must not immediately, or at a later instance, be precipitated from this solution, but can be formed, for example, when other conditions are fulfilled, e.g. such standing in relation to the reaction kinetics. At the same time, a mineral found to be anJersaturated does not have to become dissolved immediately or at a later time - after all, it is possible that this mineral will never come in contact with the solution. The result of such a model calculation should just be understood as the statement that certain minerals can be either dissolved or precipitated. It goes without saying that mostly such minerals are of particular interest that have a calculated saturation index close to zero, because this circumstance often refers to set equilibria and hence to corresponding reactions. 

The principles of homogeneous reaction kinetics and the equations derived there remain valid for the kinetics of heterogeneous catalytic reactions, provided that the concentrations and temperatures substituted in the equations are really those prevailing at the point of reaction. The formation of a surface complex is an essential feature of reactions catalyzed by solids and the kinetic equation must account for this. In addition, transport processes may influence the overall rate heat and mass transfer between the fluid and the solid or inside the porous solid, > that the conditions over the local reation site do not correspond to those in the bulk fluid around the catalyst particle. Figure 2.1-1 shows the seven steps involved when a molecule moves into the catalyst, reacts, and the product moves back to the bulk fluid stream. To simplify the notation the index s, referring to concentrations inside the solid, will be dropped in this chapter. 

Investigation of the reaction kinetics in an inert atmosphere using DSC confirms the difference between evaporation and cracking processes. However, the extrapolated onset temperatures of the evaporation exceed the T5 % index numbers of thermogravimetry considerably. On the contrary the start temperatures (onset) of the cracking reaction in DSC were found at nearly equal temperatures, to those from thermogravimetry, T ... 

The enzymatic reaction kinetics on the HRP-catalyzed oxidation of p-cresol in aqueous 1,4-dioxane or methanol showed that the cataljdic turnover niunber and Michaelis constant were larger than those in water (235). Numerical and Monte Carlo simulations of the peroxidase-catalyzed polymerization of phenols were demonstrated (236). The simulations predicted the monomer reactivity and polymer molecular weight, leading to synthesis of polymers with specific molecular weight and index. In an aqueous 1,4-dioxane, the formation of monomer aggregate was observed (237), which might elucidate the specific polymerization behaviors in such a medium. 

The techniques for measuring rate constants and prodnct distribntion (branching ratios) for ion-molecule reactions are varied, but the majority of the data have been determined using the FA, drift-tube (DT), selected ion flow tube (SIFT), high-pressure mass spectrometric techniques, or ICR. These methods are detailed in Chap. 4. A number of surveys of all classes of ion-molecule reactions have appeared in the literature Ferguson [16], Sieck et al. [17], Albritton [18], Anicichet al. [19], Ikezoe et al. [20], some of which include termolecular reactions or are limited to selected methods. Anicich listed [21] an index to the hterature for gas phase bimolecular positive ion-molecule reactions as a comprehensive survey of ion-molecule reaction kinetics and product distribution of the reactions. Over 2300 references are cited. This index covers the hterature from 1936 to 2003. It was limited to selected reactions, listed by reactant ion, that were important for chemical modehng ionic processes in planetary atmospheres, cometary comas, and intersteUar clouds. 

Anicich VG. An index of the literature for bimolecular gas phase cation-molecule reaction kinetics. JPL Publication U.S. (03-19) 2003. p. 1172... 

For application in fluidization and fluid-particle systems, the attrition index is probably the most important particle characteristic. The particle attrition can affect the entrainment and elutriation from a fluidized bed and thus subsequently dictate the design of downstream equipment. The attrition in a pneumatic transport line can change the particle size distribution of the feed material into a fluidized bed reactor and thus alter the reaction kinetics. Davuluri and Knowlton (1998) have developed standardized procedures to evaluate the Attrition Index employing two techniques, solids impaction on a plate and the Davison jet cup. The two test units used are shown in Figs. 6 and 7. They found that these two test techniques are versatile enough to be applicable for a wide range of materials, such as plastic, alumina, and lime-... 

In Section 1.4 the topological concept of rotation was used to prove the existence of equilibrium states. When the reaction kinetics are not restricted by Postulate 1.5.1, each invariant manifold may include more than one equilibrium states and it is interesting to obtain information about the number and stability of these states. In the present section we shall use one more topological concept, the index of a fixed point, to show that the equilibrium states are odd in number, 2m+1, among which m at least are unstable. As in the preceding sections, the discussion concerns isolated systems, but extension to other closed systems should not present difficulties. 

Anicich, V.G., 2003. An Index of the Literature for Bimolecular Gas Phase Cation-Molecule Reaction Kinetics. Jet Propulsion I-aboratory—California Institute of Technology, Pasadena, CA, USA, p.ll94, JPI--Ihiblication-03-19. 

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