The liquid phase hydrocarbon oxidation is studied in a packed bed membrane reactor. A mathematical model is developed, reaction simulations are performed and interpreted using the conversion, organic peroxide efficiency and oxidation product separation factor. The influence of several process parameters, such as space time, overall membrane mass transfer coefficient and aqueous-organic phase distribution coefficient is investigated. A substantial increase in organic peroxide efficiency was observed in the packed bed membrane reactor configuration as compared to a conventional packed bed reactor. (C) 1999 Elsevier Science Ltd. All rights reserved.