The application of surfactant systems is an excitingly new concept to perform reactive separations. One of the applications is the incorporation of homogeneous catalysts in micelles to perform reactions: micellar catalysis. Nonpolar reactants are converted into polar products, using the micelles as nano-reactors. The polar products are extracted towards the surrounding water phase, allowing for selectivity tuning. In this study, propene and I-octene have been successfully epoxidized by hydrogen peroxide, catalysed by micelle-incorporated porphyrin catalysts. Preliminary experiments show that an ultrafiltration membrane can retain the micelles containing the homogeneous catalyst. This opens up the industrial application of homogeneous catalysis for the production of commodity chemicals. (C) 2003 Elsevier Science B.V. All rights reserved.