This paper studied the surface functional groups and oxidation reactivity of soot in a methane/air diffusion flame at different heights above the burner(HAB)and analyzed the correlations between surface functional groups and the oxidation reactivity of soot. The soot was collected from an in-situ capillary sampling system and analyzed by Fou-rier transform infrared spectrometer(FT-IR),X-ray photoelectron spectrometer(XPS)and thermo gravimetric ana-lyzer(TGA). The results show that the content of both aliphatic C—H and oxygenated surface functional groups in-creases firstly and then decreases with the increase ofHAB. However,the apparent activation energies for the oxida-tion of soot decrease firstly and then increase with the increase ofHAB. Surface functional groups have a definite im-pact on the oxidation reactivity of soot,and higher content of surface functional groups leads to higher oxidation re-activity of soot. The content of aliphatic C—H functional groups acts as a more important factor in governing the soot oxidation than either of the two oxygenated functional groups.%基于甲烷/空气扩散火焰燃烧系统(初始温度25,℃,甲烷/空气流速比2:1)及毛细管取样技术,结合傅里叶变换红外光谱仪(FT-IR)、X射线光电子能谱仪(XPS)和热重分析仪(TGA),研究不同火焰高度碳烟颗粒表面官能团及其氧化活性,并分析了表面官能团对氧化活性的影响.结果表明:随着火焰高度的增加,碳烟颗粒表面脂肪族C—H 官能团和含氧官能团(C—OH 和 C=O)的含量呈先升高后降低的趋势,而其氧化特性温度参数和表观活化能则呈先降低后升高的趋势;碳烟颗粒表面官能团对其氧化活性有着直接的影响,表面官能团含量越多,其氧化活性也就越高;碳烟颗粒表面的脂肪族 C—H 官能团含量对其氧化活性的影响起着更为主要的作用,而含氧官能团含量则起着相对次要的作用.
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