A comparative oxidation of cyclohexane catalyzed by N-hydroxyphthalimide and ZSM-5 supported Co(II), Mn(II), Ni(II), Zn(II), Fe(III) with molecular oxygen in the absence of solvents and reductants

A catalytic system consisting of ZSM-5 supported metal ions (M/ZSM-5) and N-hydroxyphthalimide (NHPI) for the selective oxidation of cyclohexane with dioxygen was reported, and the catalytic activity of various M/ZSM-5 was investigated. Cyclohexane was successfully oxidized in good conversion, the highest conversion of cyclohexane could be obtained using Co(II)/ZSM-5 and NHPI, however, the highest selectivity of adipic acid was from Mn(II)/ZSM-5 and NHPI. The stability and recycling of the catalyst were also reviewed.