Aromatic nitration by mixed acid is one of the most widely used reactions in the organic chemical industries. Aromatic nitro compounds find wide use in the manufacture of dyes, drugs, polymers, solvents, agrochemicals and explosives. In this book, nitration of nitrobenzene using high-concentrations of sulfuric acid is described in a batch reactor at 298 K and at moderately higher temperatures. Various physicochemical properties of the nitrobenzene, sulfuric acid and nitric acid system are reported. The mass transfer coefficients of nitrobenzene in aqueous sulfuric acid solutions of different concentrations at different stirring speeds, and the reaction rate constants are reported at these temperatures. The activation energies of the reactions are also reported. A mathematical model is presented for simultaneous mass transfer and chemical reaction. The yields of the three isomers of dinitrobenzene and the isomer distributions at various sulfuric acid concentrations and temperatures are reported. The information presented in this book will be useful to the chemists and chemical engineers involved in the study of aromatic nitration.