Transformation of acetaminophen using manganese dioxide − mediated oxidative processes: Reaction rates and pathways

► APAP was rapidly oxidized by δ-MnO2. ► APAP transformation were increased with the decreased pH or increased temperature. ► APAP transformation was inhibited by some inorganic ions and phenols co-solutes. ► The UV-Vis spectra show that APAP may polymerize to form oligomer. ► The products of APAP were formed by the coupling oxidation of aromatic carbon.