Effect of Nickel Promoted Niobium Catalyst on Toluene Nitration Reaction

A series of Ni–Nb₂O₅/SiO₂ catalysts with varying Ni loadings (5–25 wt %) were prepared. The catalytic activity of the materials was evaluated by nitration of toluene. Ni–Nb₂O₅/SiO₂ catalyst showed good catalytic activity, selectivity, and reusability for the nitration of toluene. Under the optimal conditions, conversion of toluene by 88% to mononitrotoluene was achieved with 100% selectivity. Experiments were designed by the Minitab software, and the effect of reaction conditions was investigated. The optimal reaction condition was also achieved for the high amount of total products and the lowest amount of meta-isomer using this software. The reusability of catalyst also was studied in this work at the same operating conditions, and the catalyst was stable for four runs without losing catalytic activity.