Kinetic and thermodynamic reaction

Example 7.5. Reversible competing reactions kinetic and thermodynamic reaction control [4]... 

One can add reverse reactions to the parallel reaction model to illustrate what chemists refer to as kinetic and thermodynamic reaction control. Often a reactant A can form two (or more) products, one of which (B) is formed rapidly (the kinetic product) and another (C) which forms more slowly (the thermodynamic... 

Figure 7.7. Plot of the numbers of A, B, and C ingredients illustrating kinetic and thermodynamic reaction control as described in Example 7.5...

The reaction can be truly adiabatic for a wide range of experimental conditions. It initiates in the kinetic region and reaches a limit of 94-96 % conversion, which corresponds to the topological limit for these systems 5>14, l617-5169). The reaction kinetics is well described by the adopted mechanism 51,69 and the resulting experimental kinetic and thermodynamic reaction parameters are similar to those obtained in isothermal experiments. 

Figure 24 Illustration of kinetic and thermodynamic reaction control B is the kinetically favored product (higher probability of formation from A), and C is the thermodynamically favored product (greater equilibrium constant with A).

The anomeric oxygen activations described above could not fulfill the requirements put forward. Either they failed to provide both activated intermediates or both anomeric glycosides were not obtained. Obviously, for a stereocontrolled activation of the anomeric oxygen, the anomerisation of the 1-OH, or the 1-0", group in the presence of base has to be taken into account (Scheme 16). Thus, in a reversible activation process and with the help of kinetic and thermodynamic reaction control both activated anom-ers should eventually be obtainable. 

NaH, both anomers can be isolated in pure form and high yield via kinetic and thermodynamic reaction control. Both anomers are thermally stable and can be stored easily. 

Provided that the necessary amount of physicochemical substance data as well as kinetic and thermodynamic reaction data has thoroughly been obtained experimentally, one can choose today whether to base the vent design for a monoproduction process on either a steady model or on a simulation of the dynamic reactor behaviour with the help of specifically developed computer codes, such as e.g. SAFIRE and RELIEF . 

Zogg, A. Fischer, U. Hungerbuehler, K. (2004). Identification of kinetic and thermodynamic reaction parameters from online calorimetric and IR-ATR data using a new combined evaluation algorithm. Chemical Engineering Science, Vol.59, No.24, 5795-5806, ISSN 0009-2509... 

Table 3. Values of kinetic and thermodynamic reactions for back reactions (T=363 K)...

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