High-selective Ni-MgO catalysts for a clean obtention of 2-phenylethanol

Abstract

High-selective to 2-phenylethanol Ni-MgO catalysts have been obtained for the hydrogenation of styrene oxide in the liquid phase. This catalytic process constitutes an environment friendly alternative to the industrial traditional methods used to obtain this product, which is widely applied in the perfume industry due to its pleasant roses smell. Three bulk Ni and two Ni-MgO catalysts were prepared, characterized and tested for this reaction. Also, a commercial Raney-Ni catalyst was studied at the same reaction conditions for comparison. The nickel morphologic characteristics and the presence of magnesia in the catalysts play an important role in their catalytic behaviour. The bulk nickel catalysts prepared not only show high selectivity to 2-phenylethanol (60–95%) but also give to the formation of condensation products, which block the active centres, decreasing their conversion. On the other hand, the presence of magnesia, through its basicity, minimizes the ethylbenzene formation, and avoids the formation of the condensation products. Thus, the Ni-MgO catalyst prepared with the highest magnesia content showed 100% of selectivity to 2-phenylethanol for a total conversion despite having much lower metallic area than a commercial Raney-Ni.