The influences of the gas rate dissolution and mass-transfer limitation atthe interfaces on selectivity of gas-liquid processes in stirred reactors with a suspended catalyst

A complex mathematical model accounting for the hydrogen dissolution proces s in suspensions and mass-transfer steps at the Liquid-solid interface for the gas and Liquid components is given. The calculated data according to th e model for the reaction A --> B --> C shows, that the yield of an intermed iate product B is very much affected by the relation of the gas component m ass-transfer coefficient on the gas-liquid interface to that on the liquid- solid one. The hydrogenation of chlornitroaromatic compounds was analysed. The kinetics of the catalytic reduction of p-chlornitrobenzene to p-chloran iline via corresponding arylhydroxilamine on the Ir/C catalyst experimental ly in a batch reactor has been studied. In this process the first reactions depend on the hydrogen concentration but the second ones are not dependent - this is a disproportion of the intermediate product to the final product - amine. (C) 2001 Elsevier Science B.V. All rights reserved.