Abstract:

Non-thermal plasma-photocatalysis （NTP-P） is employed to remove the toluene existing in volatile organic compounds （VOCs）. The mechanisms of toluene removal including the reaction mechanism and the macrodynamics are then analyzed in the case of adding 02 and Ar to the NTP-P system. The results show that photocatalyst TiO₂ improves the removal rate of toluene in not only the nitrogen plasma field （NTP-P-O₂/N₂） eradiating ultraviolet light but also the argon plasma field （NTP-P-Ar） eradiating visible light. This supports the idea that both the UV light and the high-energy electron in the plasma field can activate TiO₂. Furthermore, the toluene removal rate in NTP-P-Ar system is 5% higher than that in NTP-P-O₂/N₂ system, confirming that high-energy electron has greater effect on the degradation performance of toluene, as compared with UV light. Based on the classical kinetic analysis method, a dynamic model of toluene degradation in non-thermal plasma-photocatalysis system is established, whose validity is proved from the consistency between the calculated data and the experimental ones.

Key words: non-thermal plasma, photocatalysis, titania, toluene, reaction mechanism, degradation dynamics