The Fenton reaction is the oxidation of ferrous iron (Fe2+) by hydrogen peroxide (H2O2) for the generation of hydroxyl radicals. The hydroxyl radicals can be used to oxidize and dechlorinate toxic organics. Typical application of the Fenton reaction involves the reaction of Fe2+ and H2O2 in homogeneous solution. This study focused on synthesizing a membrane that could serve as the hydroxyl-radical generation sites and the reaction medium for the dechlorination. The model species used for the dechlorination study was pentachlorophenol (PCP). This is a common wood preservative and also has many other applications: insecticides, herbicides, etc. There have been several reported cases of PCP contamination of soil and groundwater. The membrane is especially useful because it allows for the immobilization of the Fe2+ through ion exchange with COOH functional groups in membrane pores. This could potentially allow for reuse of membranes. Also, the typical Fenton reaction can only take place at low pH (pH 3). This is because, Fe2+ in solution precipitates as a hydroxide at and above pH 6. Thus, by immobilizing the Fe2+ within a membrane, the precipitation of iron hydroxide is eliminated and Fenton's reaction can be employed at near neutral conditions. This study utilized polyacrylic acid (PAA) functionalized polyvinylidene fluoride (PVDF) microfiltration membranes. The PVDF membrane was chosen for its non-reactive nature. 5.85 mg of Fe2+ was immobilized in the membrane. This membrane system was shown to degrade H2O2 consistently up to 40%. PCP dechlorination was studied by studying chloride generation during the membrane reaction. The experimental results with membrane systems include: Fe(II) to Fe(III) conversion by H2O2, degradation rates of H202, and PCP dechlorination. This research has been supported by the NSF-REU program and by NIEHS.