O2介质阻挡放电微等离子体制备O3

Preparation of O3 by O2 DBD microplasma

介质阻挡放电(DBD)是工业生产臭氧(O3)最有效的方法。研究以O2为原料气采用DBD微等离子体放电制备O3,研究了放电间距、放电长度、放电功率以及停留时间对产生O3的影响。此外,通过向正弦AC等离子体电源中叠加调制脉冲,探讨了脉冲占空比与调制频率对O3生成的影响。结果表明:O3浓度与DBD反应器的放电间距呈负相关,与O2的停留时间呈正相关,放电功率及有效放电长度对O3浓度的影响呈现火山形变化趋势。综合考虑O3浓度及能量产率确定了适宜的参数。与普通正弦交流电源相比,在其基础上叠加脉冲调制电源有利于O3的产生,而能量产率与占空比呈正相关,与调制频率呈负相关,据此确定了合适的占空比与调制频率。

Dielectric barrier discharge(DBD)is considered to be the most efficient method for industrial production of ozone(O3).O3 was prepared by using DBD microplasma discharge with O2 as the raw material gas.The effects of the discharge interval,discharge length,discharge power and residence time on the production of O3 were studied.In addition,the modulated pulse was added to the sinusoidal AC power supply,and studied the effect of pulse duty cycle and modulation frequency.The results showed that the concentration of O3 decreased with the increase of discharge length,while the energy efficiency increased first and then decreased.At the discharge length of 0.75 mm,both were in a higher range.Excessive or too small discharge length was not conducive to the formation of O3.The suitable discharge length was 80-90 mm.With the increase of discharge power,the concentration of O3 rose first and then decreased,and the energy efficiency decreased almost linearly.The residence time of O2 was positively correlated with the concentration of O3,and negatively correlated with energy efficiency.The optimal discharge power was(6.7±0.2)W,and the appropriate residence time was 1.0-1.4 s.It was found that the superposition of pulse modulation power supply on the basis of common sinusoidal alternating current is beneficial to the generation of O3,and the energy efficiency decreased with the increase of the duty cycle,increased with the enhancement of the modulation frequency.The appropriate duty cycle and modulation frequency was 60%,800 Hz,respectively.