介质阻挡放电中OH自由基对甲醛脱除的影响

Effect of OH Radicals on Formaldehyde Removal in Dielectric Barrier Discharge

对管线式介质阻挡放电中的甲醛脱除进行了实验研究,测量了介质阻挡放电产生的OH(A2Σ→X2Π,0-0)自由基发射光谱.研究了在一个大气压下不同放电峰值电压、放电频率、添加氩气和氧气时甲醛脱除率与OH自由基发射光谱强度的变化关系.实验结果表明:在氮气含甲醛体系中,提高放电峰值电压、放电频率和增大氩气含量时,甲醛脱除率随OH(A2Σ→X2Π,0-0)自由基发射光谱强度的增强而提高;当在氮气含甲醛体系中增大氧气含量时,甲醛脱除率随OH(A2Σ→X2Π,0-0)自由基发射光谱强度的减弱而降低.在11.5kV放电峰值电压和9kHz放电频率下,氮气含甲醛体系中甲醛脱除率达93.8%.

The removal of formaldehyde by dielectric barrier discharge in a coaxial cylindrical reactor has been studied at atmospheric pressure. The emission spectra of OH （A^2∑→X^2π,0-0） emitted from the dielectric barrier discharge have been successfully recorded. The relationship between the removal efficiency of formaldehyde and the emission intensity of OH （A^2∑→X^2π,0-0） has been investigated at different applied voltages, driving frequencies, concentrations of argon and oxygen. We find that the removal efficiency of HCHO increases when the emission intensity of OH （A^2∑→X^2π,0-0） increases with rising applied voltage, driving frequency, and concentration of argon. However, the removal efficiency of HCHO decreases when the emission intensity of OH （A^2∑→X^2π,0-0） decreases with an increase in the concentration of oxygen. The removal efficiency of HCHO is 93.8% in N2＋HCHO mixed gas at 11.5 kV applied voltage and 9 kHz driving frequency.