Efficient mineralization of a novel fluorotelomer surfactant, 2H, 3H,3H,5H,5H, 6H, 6H-4-thia-perfluoro(2-methyl)-1-dodecanoic acid, in superheated water induced by a combination of potassium permanganate and dioxygen

Mineralization of a fluorotelomer surfactant containing a C(6)F(13 )end-group (FSC), in hot and superheated water was studied. The process was optimized by variation of parameters such as temperature and the presence or absence of O-2, Ar, KMnO4 and K2S2O8. Treatment of FSC with a combination of KMnO4 and O-2 efficiently decomposed the surfactant to F-, SO42-, and CO2. Specifically, when aqueous FSC (34.8 mu mol) and KMnO4 (0.50 mmol) were reacted at 350 degrees C for 18 h under O-2 (13.6 mmol), the F-, CO2, and SO42- yields reached 82, 84, and 97%, respectively, that is, most of fluorine, carbon, and sulfur atoms were mineralized. 1H-Perfluoroalkanes (CnF2n+1H, n = 1-6) were detected as minor products in the gas phase, in amounts that decreased with increasing reaction time. Taken together, these major and minor products accounted for 96% of the fluorine, 97% of the sulfur, and 91% of the carbon atoms in the initial FSC. The in situ formed MnO2 dominantly acted as the oxidizing agent for the mineralization of FSC.

Automated summary

The mineralization of a fluorotelomer surfactant in hot water was studied, and by optimizing conditions such as temperature and the presence of various chemicals, it was found that a combination of KMnO4 and O-2 efficiently decomposed the surfactant into F-, SO42-, and CO2. Minor products of perfluoroalkanes were detected in the gas phase, with majority and minor products accounting for high percentages of initial materials. The in situ formed MnO2 played a dominant role in the oxidation of the surfactant.