Home Page

Solvent effects in liquid phase heterogeneous catalysis

Several liquid phase catalytic reactions show large variations in activity or selectivity when the solvent is changed. The reasons for this are not well understood and the primary aim of this project is to develop a fundamental understanding of the interactions between liquids and solids that will help us to understand such solvent effects.

An example of the effect of the solvent on a liquid phase reaction is the hydrogenation of  benzylacetone:

 

The dramatic effect of the choice of solvent on the activity is shown below:

 

The selectivity to different products is also affected by the solvent:

SELECTIVITY TO CYCLOHEXYLBUTAN-2-OL

 

SELECTIVITY TO PHENYLBUTANOL

Nuclear magnetic resonance (NMR) can be used as a probe to see if there are different interactions between the benzylacetone and the solvents. The results for the CH2 resonances in different solvents, as shown below, indicate that there are different interactions: