BRs FOR TWO- AND THREE-PHASE PROCESSES

The gas-liquid and liquid-solid mass transfer resistances are suppressed by vigorous agitation of the reactor contents, and the mass transfer resistance inside the catalyst particles is minimized by using finely dispersed particles (of micrometer scale). The addition of the gas-phase component is controlled by pressure regulation thus, the pressure in the gas phase is kept constant, which implies that the mass balance of the gas phase can be excluded from the mathematical treatment. The concentrations of dissolved gases in the liquid phase are equal to the saturation concentrations (Chapter 6). Under these circumstances, the mass 

FIGURE A9.8 Test reactors (autoclave and shaking reactor) for the measurement of the kinetics of three-phase processes. 

As shown by Equation A9.18, the formal treatment of the data obtained from the slurry reactor is similar to the procedure for the homogeneous BRs. The only difference arises from using the proportionality factor, that is, the catalyst bulk density, pb. 

For noncatalytic and homogeneously catalyzed gas-liquid reaction systems, BRs are frequently used. Provided that the reactor operates at the kinetic regime (mass transfer resistances and reactions in the films are negligible see Chapter 7), the component mass balance is given by 

FIGURE A9.9 Verification of the kinetic regime for a three-phase process in a slurry reactor (O, X, represent various catalyst amounts). 

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