Aromatic sulfonation. Part 23: Sulfonation of p‐xylene in aqueous sulfuric acid

The rate of the homogeneous sulfonation of p-xylene in aqueous sulfuric acid varying in concentration from 72 to 89% H2SO4 has been determined. Pseudo first order rate constants and apparent activation energies are reported as a function of the sulfuric acid concentration. The mechanism of the sulfonation of p-xylene is briefly discussed.