Rapid photolysis of H₂S and the mechanism using high-frequency discharge electrodeless lamp

ABSTRACT

In the present study, the H₂S photolysis using the self-made high-frequency discharge electrodeless lamp (light distribution was 90% at 254 nm and 10% at 185 nm) was studied and simulated by MATLAB software. Firstly, the effects of the initial H₂S concentration, irradiation time, oxygen content and relative humidity on H₂S photolysis efficiency were experimentally investigated. The results indicated that the photolysis efficiency decreased from 100% to 90.13% with the increase in the initial concentration from 3 to 30 mg/m³, and the main product was H₂SO₄. With the relative humidity increased from 0% to 99%, H₂S photolysis efficiency was obviously improved under different atmospheres (O₂> air > Ar), indicating the significant effect of relative humidity and oxygen concentration. The simulation results were consistent with the experimental results, indicating the feasibility of the simulation model. Moreover, based on the photoreactions, model simulation and equilibrium analysis of sulphur species, the photodegradation pathway of H₂S was further inferred. H₂S was oxidized to H₂SO₄ by O₃ and other strong oxidizing radicals excited by 185 nm UV light.

GRAPHICAL ABSTRACT

KEYWORDS:

• H₂S photolysis
• high-frequency discharge electrodeless lamp
• simulation model
• influencing factors
• photolysis mechanism

Acknowledgements

We gratefully acknowledge the financial support of the development of Startup Foundation for Doctors (GC300502-18, GC300502-26), Department of Education of Guangdong Province (2017GKTSCX066).

Disclosure statement

No potential conflict of interest was reported by the author(s).

Additional information

Funding

We gratefully acknowledge the financial support of the development of Startup Foundation for Doctors (GC300502-18, GC300502-26), Department of Education of Guangdong Province (2017GKTSCX066).