摘要
通过添加不同焦粉含量的煤焦油沥青非等温中间相转化动力学研究，测定了中间相转化动力学参数。并借助偏光显微镜对热转化残留物的光学显微结构进行了观察。结果表明，煤焦油沥青中间相转化属于一级动力学反应．在400-500℃其表观活化能为222．6-241．8kJ／mol。添加焦粉降低了中间相转化活化能，加快了中间相转化速率，缩短了中间相转化特征温度区间．导致热转化残留物中形成大量镶嵌结构，不利于针状焦光学显微结构生成。随着焦粉添加量的增加，这种不利影响加剧。
In the paper, the non-isothermal kinetics of mesophase transformation for coal tar pitches with addition of different amount of coke powder was studied and some kinetic parameters were obtained. The microstructures of the resultant residues after mesophase transformation were analyzed by the polarizing optical microscope. The result shows that the transformation of the mesophase for coal tar pitch belongs to the first order kinetic reaction and its apparent activation energy at the temperatures from 400 ℃ to 500 ℃ is in the range of 222.6-241.8 kJ/mol. The addition of coke powder can decrease the activation energy of mesophase transformation, increase the rate of mesophase transformation and shorten its characteristic temperature range, leading to the formation of lots of mosaic structures in the optical textures of thermal transformation residue. These are disadvantage to the formation of optical texture of needle coke. The harmful effect of coke powder on the mesophase transformation is intensified with increasing the amount of coke powder in coal tar pitch.
出处
《炭素技术》
CAS
北大核心
2014年第4期1-4,13,共5页
Carbon Techniques
关键词
煤沥青
中间相转化
非等温动力学
Coal tar pitch
mesophase transformation
non-isothermal kinetics
