Selective Nitration of Chlorobenzene on Super-acidic Metal Oxides

Abstract: The solid catalysts of SO42-/TiO2, SO42-/TiO2-ZrO2, SO42-/WO3-ZrO2, and SO42-/MoO3-ZrO2 have been prepared and regioselectiveties of chlorobenzene minonitration on these catalysts were investigated. When the reaction was carried out at 30 °C for 30 min, SO42-/TiO2-ZrO2(1:1) by a calcination step for 3 h at 550 °C enhanced the para-selectivity of chlorobenzene nitration by using nitric acid as nitrating agent, up to an ortho-para isomer ratio 0.17 in product distribution of chlorobenzene mono- nitration, and the yield of chlorobenzene mononitration was 55%. The catalysts could be reutilized for four times with a little decrease in activity