Copper-based catalysts prepared from hydrotalcite precursors for shift reaction at low temperatures

CuO/ZnO/Al2O3 catalysts were prepared from calcination of hydrotalcite-like compounds obtained by co-precipitation of Cu, Zn and Al nitrates. The characterization of the hydrotalcite-derived catalyst by XRD showed the formation of CuO and ZnO, with small contribution of spinel phase and diameter of CuO crystallite of about 10 nm; TPR analysis showed a higher reduction temperature due to the higher interaction of copper species with support. The commercial and synthesized catalysts were tested in the low temperature shift reaction. In the activity test, the commercial catalyst showed a higher conversion. On the other hand, in the stability test at 250 °C, the 30CuHTc catalyst showed the lower decrease in the activity, which can be attributed to its higher resistance to sinterization since the interaction of copper with the support helps to maintain the metallic dispersion with time on stream.