Integral reactor, catalytic reaction rate data

Tubular Reactors. The tubular reactor is exceUent for obtaining data for fast thermal or catalytic reactions, especiaHy for gaseous feeds. With sufficient volume or catalyst, high conversions, as would take place in a large-scale unit, are obtained conversion represents the integral value of reaction over the length of the tube. Short tubes or pancake-shaped beds are used as differential reactors to obtain instantaneous reaction rates, which can be computed directly because composition changes can be treated as differential amounts. Initial reaction rates are obtained with a fresh feed. Reaction rates at... 

Equation 8.3.4 may also be used in the analysis of kinetic data taken in laboratory scale stirred tank reactors. One may directly determine the reaction rate from a knowledge of the reactor volume, flow rate through the reactor, and stream compositions. The fact that one may determine the rate directly and without integration makes stirred tank reactors particularly attractive for use in studies of reactions with complex rate expressions (e.g., enzymatic or heterogeneous catalytic reactions) or of systems in which multiple reactions take place. 

The kinetic modelling of complex multiphase catalytic reactions needs a careful consideration of various complexities of adsorption and desorption of reactants and products. In such cases the kinetic model developed based on the initial rate data may not be adequate to explain the integral batch reactor performance. Hence it was thought appropriate to use mainly the integral rate data for developing a suitable kinetic model. Different rate equations were derived based on various Langumir-Hinshelwood mechanisms and a few of them are given below. 

The intrinsic kinetic data obtained from an integral reactor operated at 4 atm and 488°K are given below for the catalytic reaction, A 2B + D. The bulk volume of catalyst is 20 cm and the feed rate is 30 1/hr. Obtain a power-law rate expression that best fits the data. 

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