Effect of discharge parameters on mercury oxidation efficiency in pulsed corona discharge

Non-thermal plasma (NTP) technology is effective for oxidation of atmospheric elemental mercury. This study focuses on the critical power supply parameters, including voltage, frequency, and pulse width, in a nanosecond pulsed corona discharge system and systematically investigates their influence on both Hg0 oxidation and ozone generation under varying discharge conditions. Experimental results demonstrate that increasing the pulse voltage significantly enhances the discharge intensity and the generation of reactive species, thereby raising the Hg0 oxidation rate to above 90%. Increasing the discharge frequency leads to a higher overall energy input per unit time and further improves Hg0 oxidation efficiency, although the energy per pulse reduces slightly. But changing the pulse width in the range of 400–2000 ns, the Hg0 oxidation rate exhibits only minor variation, remaining nearly constant at approximately 90%. These findings provide a theoretical basis and parameter optimization strategy for the industrial application of non-thermal plasma in atmospheric mercury pollution control.