Efficient degradation of mordant blue 9 using the fenton-activated persulfate system

In this study, a Fenton-activated persulfate (Fe2+ /PS) system was introduced for the efficient degradation of Mordant Blue 9 (MB 9) as a textile dye in an aqueous solution. Results showed that the degradation of MB 9 was markedly influenced by operational parameters, such as initial pH, PS concentration, Fe2+ concentration, and initial dye concentration. Optimal reaction conditions were then determined. Inorganic anions, such as Cl− and HCO−3, enhanced the degradation efficiency of MB 9 under optimal conditions. Addition of HCO−3 reduced the degradation performance of MB 9, whereas the addition of Cl− increased the degradation percentage of MB 9. In addition, quenching experiments were conducted using methanol and tert-butyl alcohol as scavengers, and methanol was identified as an effective scavenger. Thus, the degradation of MB 9 was attributed to SO•− 4 and• OH radicals. The degradation and mineralization efficiency of MB 9 was significantly reduced using the conventional Fenton process i.e., Fe2+ / hydrogen peroxide (HP) because of the formation of a Fe complex during degradation. Meanwhile, the Fe2+ /persulfate (PS) system improved the degradation and mineralization performance. © 2019 by the authors. Licensee MDPI, Basel, Switzerland.