Synergetic effect of the mineralization of organic contaminants by a combined use of permanganate and peroxymonosulfate

A novel bi-component oxidizing system of KMnO4 and peroxymonosulfate (PMS, in the form of Oxone®) is proposed for mineralization of organic contaminants. Our results demonstrated that the combined use of KMnO4 and PMS (CUPP) caused a synergetic effect on the mineralization of organics in solution. The reduction products of KMnO4, suspended particulate MnO2, activated the subsequently added PMS, promoting the sulfate radicals-involved oxidation of acid orange 7 (AO7) and degradation intermediates. The suspended amorphous MnO2, as the PMS activator, featured a so-called sea urchin nanostructure with many flakes radiating from its center. The addition of Oxone acidified the solution and, in turn, improved the reactivity of KMnO4. The results indicated that the time interval between KMnO4 and Oxone additions did not impact the efficiency of the bi-component oxidizing system. The ratio of KMnO4/PMS can be optimized to achieve the highest mineralization rate of AO7 or the best utilization of oxidants. We concluded that the combined use of KMnO4 and PMS facilitated the utilization of both oxidants and exhibited powerful oxidizing capability without the need of an additional catalyst for PMS activation. This bi-component system can be developed as an innovative chemical oxidation technology for the transformation of a variety of organic pollutants.