Deep insight into methyl blue decolorization using non-thermal pulsed plasma: experimental and modeling approaches

Area of Science:

• Environmental Science
• Chemical Engineering
• Plasma Physics

Background:

• Methyl blue (MB) dye is a common water pollutant.
• Effective and rapid dye decolorization methods are crucial for environmental remediation.
• Non-thermal plasma offers a promising approach for advanced oxidation processes.

Purpose of the Study:

• To investigate the rapid decolorization of methyl blue (MB) dye using a novel atmospheric non-thermal pulsed plasma system.
• To elucidate the degradation mechanisms through kinetic modeling and spectroscopic analysis.
• To demonstrate the efficiency and scalability of the plasma system for water treatment.

Main Methods:

• Utilized a multi-pin-to-plate electrode configuration for atmospheric non-thermal pulsed plasma generation.
• Employed optical emission spectroscopy and UV-visible absorption spectroscopy for analysis.
• Applied response surface methodology for experimental design and optimization.
• Developed a global kinetic model to simulate over 150 species and 3500 reactions.

Main Results:

• Achieved 97% decolorization of 5 ppm MB within 120 seconds under optimized conditions.
• Observed significant increases in reactive species concentrations, including hydroxyl radicals (·OH) and ozone (O3).
• Documented changes in water chemistry, such as pH, oxidation-reduction potential (ORP), and electrical conductivity (EC).

Conclusions:

• The novel atmospheric non-thermal pulsed plasma system demonstrates high efficiency and scalability for MB dye decolorization.
• The study provides new mechanistic insights into plasma-based degradation of organic pollutants.
• The developed framework can be used to optimize plasma systems for effective water treatment.