The effect of the catalyst on the synthesis of 2,2′-dichlorohydrazobenzene during the electrochemical reduction of o-chloronitrobenzene

In this paper, 2,2′-dichlorohydrazobenzene was synthesized by the electrochemical reduction of o-chloronitrobenzene using the ion-exchange membrane method. The effects of different catalysts (litharge, lead tetroxide, and lead nitrate) on the synthesis were investigated. The influence of different catalyst loading approaches on the electrochemical reduction were also examined. The structure and surface morphology of the catalysts were characterized by X-ray diffraction and scanning electron microscopy. Catalyst activity was examined by dynamic potential analyses and cyclic voltammetry. Litharge was found to induce the greatest improvement in the electrolysis reaction rate and also decreases the reaction time. Coating the catalyst on the cathode helps enhance the product yield. The possible reaction mechanism was studied, and the catalyst was found to play a key role in transforming raw substances into intermediates. However, there is little effect on intermediate product transformation into the desired product.

► 2,2′-dichlorohydrazobenzene was synthesized by electrochemical reduction. ► The ion-exchange membrane method was used in synthesis. ► The main active substance in the electrochemical reduction is litharge. ► Coating the catalyst on the cathode can improve the product yield. ► A possible reaction mechanism is proposed.