Characteristics of Potassium Permanganate Encapsulated in Polymer

Potassium permanganate was encapsulated in various polymers to create microcapsules with slow-release properties. Batch tests were conducted to evaluate the rates at which the microcapsules release permanganate. The release histories of 18 different polymer formulations varied strongly, but average initial release rate was 2.70  g KMnO4 released g KMnO4 initial1  d-1, and the release rate typically decreased with time. The total duration of release ranged from 3  to  80  days, with an average of 27  days. In other batch tests trichloroethene (TCE) was degraded to below detectable amounts by the microcapsules. The degradation rate for TCE was three to four times faster during the initial reaction period than predicted based on permanganate release rates. There appear to be several promising environmental applications for this method of creating a slow-release oxidant.