Decomposition of Dissolved Methylene Blue in Water Using a Submerged Arc Between Titanium Electrodes

作者：Parkansky Naum^*; Simon Evelina Faktorovich; Alterkop Boris A; Boxman Raymond L; Berkh O

来源：Plasma Chemistry and Plasma Processing, 2013, 33(5): 907-919.

DOI：10.1007/s11090-013-9465-5

• Submerged pulsed arc
• Electro-hydraulic discharge
• Water treatment
• Plasma
• Decontamination

Low voltage, low energy submerged pulsed arcs between Ti electrodes with a pulse repetition rate of 100 Hz, energies of 2.6-192 mJ and durations of 10-40 mu s, followed by aging in the dark, were used to decompose 10 mg/l methylene blue (MB) contamination in 40 ml aqueous solutions, with and without the addition of 0.5 % H2O2. The impact of the arc treatment on the MB removal ratio (C-0-C-ta)/C-0 was considered as a function of aging time t(a), where C-0 and C-ta are the MB concentrations initially and after t(a) (the time needed to complete removal of MB after cessation of exposure of the arc). Particles eroded from the electrodes during the discharge enabled MB decomposition during aging. The particles were studied by XRD, XPS and Raman analysis, and titanium oxides and peroxides were found. MB decomposition during aging is explained by the formation of a surface layer of titanium peroxide that forms by the interaction of titanium dioxide with H2O2, which produce radicals which oxidize the MB. The 99.6 % MB removal yield (G(99.6) = 90 g/kWhr) of the submerged pulsed arc process with Ti electrodes and addition of 0.5 % H2O2 was more than 60 times larger than obtained at 50 % removal with other plasma methods.

• 出版日期2013-10