Thermal transformation of copper incorporated hydrotalcite-derived oxides and their catalytic activity for ethanol dehydrogenation

Abstract

Thermal transformation of copper incorporated hydrotalcite-derived oxides is investigated in ethanol dehydrogenation. Among the copper supported catalyst c-10Cu/HT600 prepared by impregnation of thermally treated hydrotalcite at 600 °C with Cu(NO3)2 solution followed by a calcination provides a high catalytic activity, selectivity and stability. XRD, DR-UV, TGA, H2-TPR, CO2-TPD, TEM and XPS techniques reveal that the nature of the copper species depended on the thermal treatment process and support. Such treatment at high temperatures yields a homogeneous dispersion mixed metal oxide. After copper incorporation generated CuAl2O4 spinel structure linked to the copper oxide species can suppress copper agglomeration leading to the catalytic stability. Moreover, the c-10Cu/HT600 catalyst can provide a high activity and high selectivity to acetaldehyde even at low reaction temperatures (200 °C). However, the copper species may agglomerate to form relatively larger clusters upon increasing metal loading leading to the deactivation.