Propriedades redox da matéria orgânica isolada de material ultrafiltrado das águas do rio Paraíba do Sul

Abstract

Previous studies indicated that free radicals control organic matter redox activities. In the present study, organic matter of an ultra-filtrated material collected from seven samples taken seasonally from the Paraiba do Sul River for two years were titrated with an oxidizer (I2) in an inert atmosphere. Standrad formal potential values for the electrode MOox MO Red ranged from 0.754 to 0.786 V at a 25 °C temperature. Organic matter oxidation capacity (COx) per carbon mass variea according to pH values, and changes in COx were related to rainfall and river flow intensities.