Effective catalysts, prepared from several hydrotalcites aged with and without microwaves, for the clean obtention of 2-phenylethanol Original Research Article

Several Ni/Mg/Al hydrotalcites have been aged by different methods (conventional refluxing, conventional autoclaving, microwaves refluxing and microwaves autoclaving). The resulting catalysts have been tested in the hydrogenation of styrene oxide to obtain 2-phenylethanol, widely used in the perfumery industry. The catalysts obtained from the hydrotalcites aged under microwaves showed higher metallic areas than those obtained from the hydrotalcites aged by conventional heating. All catalysts showed total conversion and very high selectivity to 2-phenylethanol (around 95%) after 1 h of reaction. The higher metallic area and the more homogeneous distribution of low amounts of basic sites of these catalysts based on hydrotalcites when compared with other basic catalysts, as Ni-MgO systems, can explain these best catalytic results. After reusing 10 times, all catalysts showed high resistance to deactivation since they maintain high conversion and high selectivity values to 2-phenylethanol. However, some differences in their catalytic behaviour were observed that have been explained from H2-TPD studies.