Variations in surface functional groups, carbon chemical state and graphitization degree during thermal deactivation of diesel soot particles  

作　　者：Ye Liu Sijin Wu Chenyang Fan Xin Wang Fangjie Liu Haibo Chen 

机构地区：[1]Institute for Transport Studies,University of Leeds,Leeds LS29JT,UK [2]Vehicle&Transportation Engineering Institute,Henan University of Science and Technology,Luoyang 471003,China

出　　处：《Journal of Environmental Sciences》2023年第2期678-687,共10页环境科学学报（英文版）

基　　金：supported by the National Natural Science Foundation of China (No.52006054);the State Key Laboratory of Engines at Tianjin University (No.K2021-05);the European Union’s projects MODALES (No.815189);nPETS (No.954377)

摘　　要：The thermal deactivation of diesel soot particles exerts a significant influence on the control strategy for the regeneration of diesel particulate filters(DPFs).This work focused on the changes in the surface functional groups,carbon chemical state,and graphitization degree during thermal treatment in an inert gas environment at intermediate temperatures of 600℃,800℃,and 1000℃ and explore the chemical species that were desorbed from the diesel soot surface during thermal treatment using a thermogravimetric analyser coupled with a gas-chromatograph mass spectrometer(TGA-GC/MS).The surface functional groups and carbon chemical statewere characterized using Fourier transform infrared spectroscopy(FT-IR)and X-ray photoelectron spectroscopy(XPS).The graphitization degree was evaluated by means of Raman spectroscopy(RS).The concentrations of aliphatic C–H,C–OH,C=O,and O–C=O groups are reduced for diesel soot and carbon black when increasing the thermal treatment temperature,while the sp^(2)/sp^(3) hybridized ratio and graphitization degree enhance.These results provide comprehensive evidence of the decreased reactivity of soot samples.Among oxygenated functional groups,the percentage reduction during thermal treatment is the largest for the O–C=O groups owing to its worst thermodynamic stability.TGA-GC/MS results show that the aliphatic and aromatic chains and oxygenated species would be desorbed from the soot surface during 1000℃ thermal treatment of diesel soot.

关 键 词：Diesel soot particles Surface functional groups Carbon chemical state Graphitization degree Thermal deactivation 

分 类 号：X701.2[环境科学与工程—环境工程]