Copper-based Catalysts for Synthesis of Methylamines: The Effect of the Metal and the Role of the Support

Three Cu-based catalysts supported in different materials were prepared. The textural properties showed that the thermal treatment and the presence of CuO resulted in decrease of BET area. The surface areas of the Cu on alumina and zeolite decay with Cu addition, which can be attributed to the formation of CuO particles, blocking the pores. Contrary, the based like-hydrotalcite catalysts surface areas increased, which may be attributed to the destruction of the structure and formation of oxide mixtures. The acid sites with moderate strength favored the methylamines production, due to the easier desorption of products. The metallic sites affect the reaction since they provide a decrease in desorption temperature of the amines and enhance the disproportionation. The metallic sites in the based like-hydrotalcite catalysts Cu/Mg–Al enhance the formation of methylamines. The Cu/Al₂O₃ was more active and stable than the other Cu based catalysts.