煤焦油精制软沥青非等温热转化动力学研究

Study on Non-isothermal Heat Conversion Kinetics of Coal-tar Refined Soft Pitch

用热重(TG)-微分热重(DTG)-差热分析(DTα)法分析煤焦油精制软沥青及其族组成在氮气保护下,从室温到800℃的热转化过程。采用Freeman-Carroll的非等温微分法对煤焦油精制软沥青及其族组成的TG-DTG曲线进行处理。煤焦油精制软沥青各族组分的热转化动力学方程证明,自制煤焦油精制软沥青的热转化的三段反应可看成是庚烷可溶族(HS),庚烷不溶甲苯可溶族(HI-TS)和甲苯不溶喹啉可溶族(TI-QS)混合组分的连串反应;HS族段的热转化动力学属二级反应,HI-TS和TI-QS族段都属一级;其活化能和频率因子分别为:48.512,28.575,60.210 kJ/mol和3.110×107,2.328×106,1.483×107。

Composition and conversion of coal - tar refined soft pitch from room temperature to 800 ℃ under nitrogen atmosphere was analyzed by thermogravimetry - differential thermogravimetry - differential thermal analysis, and the thermo- gravimetry - differential thermogravimetry curve was treated by Freeman - Carroll differential method. Heat conversion of coal -tar refined soft pitch could be considered as a consecutive reaction of heptane soluble, heptane insoluble - toluene soluble and toluene insoluble - quinoline soluble. Reaction of heptane soluble was a second order reaction, and those of heptane insoluble - toluene soluble and toluene insoluble - quinoline soluble were first order reaction, with activation energy of 48.512, 28. 575 and 60.210 kJ/mol and frequency factor of 3.110 ×10^7, 2. 328 ×10^6 and 1. 483 ×10^7 respectively, which provided a theoretical basis for the optimizing and reasonable design of heat conversion parameters of coal - tar refined soft pitch.