O_(3)质量浓度对低温等离子体氧化柴油机PM的影响

Effect of Ozone Mass Concentration on the Oxidation of Diesel Engine PM by Non-Thermal Plasma

为高效利用臭氧(O_(3))氧化去除柴油机颗粒物(PM),探究O_(3)自身热分解规律,分析不同O_(3)质量浓度的低温等离子体(NTP)气体对柴油机颗粒物的去除量和可溶性有机物(SOF)组分的影响.基于O_(3)热分解反应方程和Arrhenius公式推导出O_(3)热分解反应动力学计算公式,分析了反应温度对O_(3)变化的影响.搭建了低温等离子体氧化去除颗粒物的试验系统,对低温等离子体作用前、后的颗粒物去除量以及SOF进行分析.结果表明:O_(3)热分解的反应活化能为2.81×10^(4) J/mol、温度为80~100℃时O_(3)具有较低的分解率和较优的反应速率.O_(3)质量浓度的提高对NTP氧化去除柴油机颗粒物的效果非常显著.低温等离子体对PM中SOF的作用主要体现在碳链的缩减,并在碳链中键入O.随着O_(3)质量浓度的增加,SOF组分中含氧基团的组分比例提高,并且组分中的含氧基团数量增多.

In order to efficiently use ozone to oxidize and remove diesel particulate matter(PM),the thermal decomposition law of ozone was explored,and the influence of non-thermal plasma(NTP)gas with different ozone mass concentrations on the removal of PM and soluble organic fraction(SOF)was analyzed.According to the reaction equation of ozone thermal decomposition,the kinetics calculation formula of ozone thermal decomposition reaction were derived and the effect of the reaction temperature on ozone was analyzed.An experimental system was established for removal of PM by NTP oxidation at different ozone mass concentrations to analyze the removal amount and SOF before and after NTP treatment.The results show that the activation energy of ozone thermal de-composition is 2.81×10^(4) J/mol and ozone presents lower decomposition rate and better reaction rate when the temperature is 80—100℃.The increase of ozone mass concentration significantly improves the effect of NTP oxidation to remove PM.The effect of NTP on the SOF in PM is mainly reflected in the reduction of the carbon chain and bonding O into the carbon chain.As the ozone mass concentration increases,the proportion and number of oxygencontaining groups increase.