Excursions into multiphase reactions

Abstract

Multiphase reactions are ubiquitous in the chemical industry and a rational analysis of reactors where they are conducted requires an intimate knowledge of chemical kinetics, thermodynamics, mass transfer and fluid mechanics. In many situations in practice, conducting reactions in multiphase systems is advantageous as compared to that in a single liquid phase system.The use of phase transfer catalysts, micellar catalysts, emulsifiers, hydrotropic agents etc., can significantly enhance the rates of multiphase reactions. A change-over from gas-liquid to liquid-liquid mode of operation could also have favourable influence. Solid-liquid reactions have received limited attention and many aspects need to be studied intensively. Three-phase reactions offer some fascinating features. The effect of solid particles, which may be sparingly soluble reactant, catalyst or even alien material, can be very substantial.Multiphase biochemical and electrochemical reactions have many unique features and such reactions are becoming increasingly important. Novel strategies of conducting multiphase reactions have been developed of late, though there are plenty of problems yet to be tackled.