A new experimental reaction cell which enables the recording of combined EXAFS/XRD data over a wide range of temperatures of a solid that catalyses liquid reactions in the liquid state has been designed and constructed. The cell is particularly suitable for the in situ study of both short-range and long-range structural changes during solid/liquid heterogeneous catalytic reactions. It is also suitable for the study of intercalation phenomena and may be readily adapted for certain types of electrochemical investigations. The use of this cell is exemplified by the oxidation of cyclohexene over a Zn(II)Al(III)-hydrotalcite containing intercalated cobalt phthalocyaninetetrasulphonate anions.