Trambouze reactions

The Trambouze Reactions—Reactions in parallel. Given the set of elementary reactions with a feed of AO = 1 mol/liter and v = 100 liters/min we wish to maximize the fractional yield, not the production of S, in a reactor arrangement of your choice. 

Example 2 The Trambouze reaction (Trambouze and Piret, 1959) involves four components and has the following reaction scheme ... 

The internal effectiveness factor is a function of the generalized Thiele modulus (see for instance Krishna and Sie (1994), Trambouze et al. (1988), and Fogler (1986). For a first-order reaction ... 

A variety of models of chemical reactors is discussed in more detail in Section 5.4. Readers who are interested in modelling of chemical reactors are also referred to books of Carberry and Varma (1987), Fogler (1986), Froment and Bischoff (1990), Levenspiel (1999), Smith (1981), Trambouze et al. (1988), Walas (1959), and Westerterp et al. (1990). With respect to heterogeneous reactions athe book of Doraiswamy and Sharma (1984) is also recommended. 

General discussions of several aspects concerning the treatment of chemical reactions with diffusion are given by Damkohler (D2), Horn and Kiichler (H12), Prager (P7), Schoenemann and Hofmann (SlO), and Trambouze (Til). Corrsin (C21) has discussed the effects of turbulence on chemical reactions from the fundamental point of view of turbulence theory. We will first discuss the application of each type of model to chemical reactors. Then a short comparison will be made between the different approaches. 

The discussion in Section III,C showed that there was no unique way to compare the stirred tank and dispersion models based on the tracer curves. Each different basis of comparison gave different results. The two models have been compared for chemical reactions by van Krevelen (V6), Trambouze (TIO), and Levenspiel (L13a). Levenspiel used Figs. 28 and 29 to determine the correspondence of the models. His results are shown in Fig. 30. The various criteria give results that differ increasingly with rise in reaction order, conversion, and degree of mixing. 

A proper laboratory or process development unit (PDU) is required if there is a lack of information on the reaction mechanism, kinetics, and the reactor hydrodynamics, especially for a new reaction system (Dutta and Gualy, 2000). In laboratory experiments, certain aspects of the process are investigated by handling small amounts of raw materials to reduce the material constraints to a minimum. In these experiments, all mechanisms that do not depend on size, such as thermodynamics and chemical kinetics, can be illuminated (Trambouze, 1990). 

Trambouze, P., Computational fluid dynamics applied to chemical reaction engineering. Rev. Inst. Francois du Petrole 48(6), 595 (1993). 

Of primary interest for the industrial application of monolith reactors is to compare them with other conventional three-phase reactors. Two main categories of three-phase reactors are slurry reactors, in which the solid catalyst is suspended, and packed-bed reactors, where the solid catalyst is fixed. Generally, the overall rate of reactions is often limited by mass transfer steps. Hence, these steps are usually considered in the choice of reactor type. Furthermore, the heat transfer characteristics of chemical reactors are of essential importance, not only due to energy costs but also due to the control mode of the reactor. In addition, the ease of handling and maintenance of the reactor have a major role in the choice of the reactor type. More extensive treatment of conventional reactors can be found in the works by Gianetto and Silveston [11], Ramachandran and Chaudhari [12], Shah [13,14], Shah and Sharma [15], and Trambouze et al. [16], among others. 

The number of independent reactions is an index of the stoichiometric complexity of the system. As Piret and Trambouze (1959) have pointed out, the expressions r, or /, may be found to contain fewer than the m concentrations. In this case it is possible to work with fewer than m equations, but integral, rather than algebraic, relations will be needed to recover the other concentrations. This observation has also been made by Horn (1961). 

Piret, E. L., and Trambouze, P. J. 1959. Continuous stirred tank reactors Designs for maximum conversions of raw material to desired product. Homogeneous reactions. A.I.Ch.E. Journal 5, 384-390. 

J. P. Vignes and P. J. Trambouze, Diffusion et Reaction Chimique dans un Reacteur Tubuiaire en Regime Laminaire, Chem. Eng. Sci., 17, 73 (1962). 

Reactant A decomposes by three simultaneous reactions to form three produc one that is desired, B, and two that are undesired. X and Y. These gas-ph reactions, along with the appropriate rate laws, arc called the Trambouze re tions [AlChEJ. 5. 384 (1959)]. 

As our first illustration we consider the co-dimerization of propene and butene to produce heptenes (Reaction 1). This reaction is accompanied by two competing, undesirable, reactions dimerization of propene to hexene (Reaction 2), and dimerization of butene to octene (Reaction 3). The second reaction proceeds extremely rapidly and in order to suppress the formation of hexenes we should have progressive injection of propene into the reactor with all the butenes at the beginning of the operation, as is shown in Fig. 22 (Trambouze et al., 1988). 

The analysis here is sufficiently general that it can be applied to liquid-liquid reactions as well, with only minor modifications [See P. Trambouze, M.T. Trambouze and E.L. Piret, Am. Soc. Chem. Eng. Jl., 7, 138 (1961).]... 

Piret,E.L., W.M.Penney and P.Trambouze. "Extractive Reaction Batch or continous flow chemical reaction systems. Dilute case" AIChEJl 6 (1960) 394-402. 

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