Atmospheric Plasma Supported by TiO2 Catalyst for Decolourisation of Reactive Orange 16 Dye in Water

Abstract

Purpose Every advanced oxidation process (AOP) has its limitations in water purification. Novel designs with simultaneous application of different AOPs can offer better solutions for cleaner water. Methods We have comparatively studied two advanced oxidation processes (AOPs) on decolourisation of Reactive Orange 16 (RO 16) azo dye pollutant from water: gas plasma treatment by low power atmospheric pressure plasma using novel plasma needle configuration, and semiconductor heterogeneous photocatalysis using titanium dioxide (TiO 2 ) nanopowders. Additionally, simultaneous application of two advanced oxidation processes on azo dye decolourisation was studied. Results It was found that plasma treatment is very efficient system for the dye removal even for low flow rates (1 slm) of the Ar as feed gas. The presence of 10% of O 2 in Ar flow intensified dye oxidation process and shortened required time for total decolourisation. When plasma and catalyst were simultaneously applied, TiO 2 was activated with a few Watts plasma source as well as 300 W UV lamp source. The synergic effect of two AOPs was more pronounced for higher feed gas flow rates, resulting in improved decolourisation efficiency. Conclusion Plasma needle can efficiently remove Reactive Orange 16 azo dye from water with a power consumption of only few Watts. With the addition of TiO 2 the removal efficiency is significantly improved.

Pathways of organic micropollutants degradation in atmospheric pressure plasma processing – A review

“…Several other authors evaluated different plasma configurations for dyes removal and up to this date, most of them concluded that the best efficiency is usually achieved when oxygen is used as a working gas. The details can be found in the reports (Iervolino et al, 2019;Jiang et al, 2012;Mitrović et al, 2020;Pankaj et al, 2017;Reddy & Subrahmanyam, 2012;Ruma et al, 2013;Sarangapani et al, 2017). (Jiang et al, 2012) time, it was founded that higher concentration of H2O2 was generated in water.…”

“…Therefore, development of an effective wastewater treatment process for dye elimination had been in the focus of interest of many researchers. Recently, several plasma systems using different type of working gas (argon, air, oxygen) have been evaluated: DBD discharge with cylindrical configuration (He et al, 2018;Iervolino et al, 2019), pin to surface configuration (Kasih et al, 2019;Mitrović et al, 2020), flow reactor system (Yamada et al, 2020), corona discharge (Ruma et al, 2013), parallel plane type DBD reactor (Reddy & Subrahmanyam, 2012).…”

“…Several studies report application of NTP in a combination with other treatments. For example, (Mitrović et al, 2020), combined NTP with titanium dioxide (TiO2) catalyst for the Reactive orange 16 (RO 16) dye degradation. The authors investigated the processes separately and in combination to compare energy efficiency of all systems.…”

Removal of chemical and microbial water pollutants by cold plasma combined with Ag/TiO2-rGO nanoparticles

“…A heterogeneous photo-oxidation process effectively using TiO 2 for removal of organic water pollutants 3 , 4 , 6 , 7 and disinfection 5 , 7 was reported. Mainly, TiO 2 is inexpensive and has been combined with plasma because it has a strong oxidation power, a reasonable bandgap, nontoxicity, and stability against photo- and chemical-corrosions 8 .…”

Non-Thermal Plasma Coupled with Catalyst for the Degradation of Water Pollutants: A Review

“…To overcome these limitations, an interesting strategy, consisting of the combination of NTP and heterogeneous catalysis, has been proposed to enhance pollutant degradation efficiency and, simultaneously, reduce the formation of reaction by-products [19][20][21]. The effect of NTP combined with catalysts enhances the generation of different types of active species (such as hydroxyls) and the activity and stability of photocatalytic materials [22][23][24][25][26]. For example, when a photocatalyst is introduced into an NTP reactor, the generation of the active species through the plasma, including ultraviolet light, can induce photocatalytic reactions, for example through the following path [27]:…”