热老化对炭黑颗粒氧化特性影响的试验研究

Experimental Investigation on the Influence of Thermal Aging on Oxidation Characteristics of Carbon Black Particles

基于热重分析仪,首先开展不同热老化温度、时间、氧气质量分数的热重试验,并分别采用微分法(Achar-Brindley-Sharp-Wendworth,ABSW)和阿仑尼乌斯法(Arrhenius)进行氧化动力学分析。结果表明:当老化温度区间在325～400℃时,随着老化温度的增加,活化能从181kJ/mol降低到170kJ/mol。随着老化时间的增加,颗粒的活化能从180kJ/mol降低到172kJ/mol之后在172kJ/mol保持不变。当老化氧气质量分数低于5%时,随着老化氧气质量分数的增加,活化能逐渐升高到188kJ/mol;而高于5%时,活化能从188kJ/mol降低到170kJ/mol。此外,基于高分辨透射电镜对炭黑颗粒的微观结构分析发现,随着老化温度、时间及氧气质量分数的降低,基本碳粒的壳结构更加趋于有序化,石墨化程度相对较高,氧化活性较低。

The thermogravimetric experiments of different thermal aging temperatures,times and oxygen concentrations were carried out by a thermogravimetric analyzer,and then the oxidation kinetics of carbon black particles was analyzed by the differential(ABSW)and Arrhenius methods,respectively.Results show that when the aging temperature is within the range of 325℃to 400℃,the activation energy of carbon black particles decreases from 181 kJ/mol to 170 kJ/mol with the thermal temperature increases.As the aging time increases,the activation energy of the particles decreases from 180 kJ/mol to 172 kJ/mol and remains unchanged.When the aged oxygen concentration is less than 5%,the activation energy gradually increases to 188 kJ/mol with the aged oxygen concentration increases,and when the aged oxygen concentration is higher than 5%,the activation energy decreases from 188 kJ/mol to 170 kJ/mol.In addition,based on the analysis of microstructure of carbon black particles by a high-resolution transmission electron microscopy,it is found that as the aging temperature,time and oxygen concentration decrease,the shell structure of basic carbon particulates tends to be more ordered,which leads to a higher degree of graphitization and lower oxidation activity.