DC magnetic field-assisted improvement of textile dye degradation efficiency with multi-capillary air bubble discharge plasma jet

Axial DC magnetic field-assisted multi-capillary underwater air bubble discharge plasma jet has been used to study the productions of reactive oxygen species. Analyses of optical emission data revealed that the rotational (T-r) and vibrational temperatures (T-v) of plasma species slightly increased with magnetic field strength. The electron temperature (T-e) and density (n(e)) increased almost linearly with magnetic field strength. T-e increased from 0.53 to 0.59 eV, whereas ne increased from 1.03 x-1015 cm(-3) to 1.33 x10(15) cm(-3) for B = 0 to B = 374 mT, respectively. Analytical results from the plasma treated water provided that the electrical conductivity (EC), oxidative reduction potential (ORP), and the concentrations of O-3 and H-2 -O2 enhanced from 155 to 229 mu S cm(-1), 141 to 17 mV, 1.34 to 1.92 mg L-1, and 5.61 to 10.92 mg L-1 due to the influence of axial DC magnetic field, while pH reduced from 5.10 to 3.93 for 30 min treatment of water with B = 0 and B = 374 mT, respectively. The model wastewater prepared with Remazol brilliant blue textile dye and the plasma treated wastewater studied by optical absorption spectrometer, Fourier transform infrared spectrometer, and gas chromatography mass spectrometer. The results show that the decolorization efficiency increased similar to 20% after 5 min treatment for the maximum B = 374 mT with respect to zero-magnetic field and, power consumption, and electrical energy cost reduced similar to 6.3% and similar to 4.5%, respectively, due to the maximum assisted axial DC magnetic field strength of 374 mT.

Automated summary

An axial DC magnetic field-assisted multi-capillary underwater air bubble discharge plasma jet was used to investigate the production of reactive oxygen species (ROS). The results showed that the rotational and vibrational temperatures of the plasma species slightly increased with magnetic field strength, while the electron temperature and density increased almost linearly. The plasma treated water exhibited enhanced electrical conductivity, oxidative reduction potential, and concentrations of O-3 and H-2-O2. Additionally, the model wastewater treated with the plasma jet demonstrated improved decolorization efficiency and reduced power consumption and electrical energy cost.