Preparation of ZnNiMo/γ-alumina catalysts from recycled Ni for hydrotreating reactions

Ni, recovered from Ni-Cd cellular phone batteries, was used in the preparation of ZnNiMo/Al2O3 catalysts. The catalysts were characterized by temperature programmed reductions (TPR), surface area determinations (BET) and chemical analysis. Vanadyl octaethyl porphyrin (VOOEP) hydrodeporphyrinization (HDP) and thiophene hydrodesulfurization (HDS) were used as catalytic tests. It was found that the addition of Zn increases the ratio between octahedral and tetrahedral Mo in ZnMo and ZnNiMo catalysts, and that Ni addition lowers the reduction temperature of Mo species. Both results induce a positive synergetic effect for HDP and HDS reactions. An activity maximum was found for the catalyst with a Zn/(Zn + Ni) atomic ratio equal to 0.29, for both reactions. Finally, the use of a possible pollutant (Ni-Cd batteries) to produce a catalyst to eliminate contaminants in fuels was shown to be feasible.