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 

作者机构：Institute for Transport StudiesUniversity of LeedsLeeds LS29JTUK Vehicle&Transportation Engineering InstituteHenan University of Science and TechnologyLuoyang 471003China 

出 版 物：《Journal of Environmental Sciences》 (环境科学学报（英文版）)

年 卷 期：2023年第124卷第2期

页      面：678-687页

核心收录：

学科分类：083002[工学-环境工程] 0830[工学-环境科学与工程（可授工学、理学、农学学位）] 08[工学] 0804[工学-仪器科学与技术] 0703[理学-化学] 

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) 

主　　题：Diesel soot particles Surface functional groups Carbon chemical state Graphitization degree Thermal deactivation 

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.