Enhanced colour removal of large molecular reactive dye by corona discharge plasma technology with Fe2+ catalysts

Abstract

This study aims to investigate the performance of corona discharge plasma in removing textile dyes, especially those with large molecular weight and complexity. Reactive Blue 21 was selected as a model contaminant due to the molecular size exceeding 1000 g/mol, contains heavy metals, nonbiodegradable, is widely used in textile industry for turquoise blue, but rarely studied, especially its removal using plasma technology. In this study, the plasma was generated by a 21 kV voltage generator connected to the point-to-plane electrode, adding O2 gas flow. The effects of pH, dye concentration, exposure time, and catalyst addition were analyzed based on the removal of color and COD from the solution. The results showed that pH, catalyst concentration, and exposure time affected dye removal efficiencies. For 60 minutes, the colour removal efficiency of Reactive Blue 21 was 73.83 % without a catalyst. The addition of a Fe2+ catalyst increased the colour removal efficiency to 100 % within 50 minutes, the dye degradation to 82.93 %, and the energy yield to 0.27 g/kWh at 60 minutes. This research proved that corona discharge plasma with Fe2+ catalyst could remove complex dye with large molecular weight, indicating its potential to eliminate all types of textile dyes.

Keywords

• Colour removal
• Large molecular weight reactive dye
• Corona discharge plasma