MULTIPHASIC CATALYSIS WITH IONIC LIQUIDS - ENGINEERING ASPECTS

3 MULTIPHASIC CATALYSIS WITH IONIC LIQUIDS - ENGINEERING ASPECTS 

Liquid-liquid multiphasic catalysis with the catalyst present in the ionic liquid phase relies on the transfer of organic substrates into the ionic liquid or reactions must occur at the phase boundary. One important parameter for the development of kinetic models (which are crucial for up-scaling and proper economic evaluation) is the location of the reaction. Does the reaction take place in the bulk of the liquid, in the diffusion layer or immediately at the surface of the ionic liquid droplets  

The answer to this question depends mainly on the relative speed of the chemical reaction vs. mass transfer of the substrate into the ionic liquid layer. If the chemical reaction is fast vs. the mass transfer rate, a significant part of the reaction will take place at the surface or in the diffusion layer. If the chemical reaction is slow relative to 

TABLE 7.2. Viscosities of selected ionic liquids with l-ethyl-3-methyHmidazohum ([EMIM]) as the cation 

It is important to be able to identify mass transfer limitations that occur when the reaction rate is high compared with the rate of mass transfer. For a heavily mass transfer limited reaction, preliminary experiments in a non optimised laboratory reactor 

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