延迟焦化石油焦热重分析及热解动力学

对延迟焦在CO2和Ar两种气氛下，从室温至1 000 ℃进行热重分析，探讨其热解机理。研究表明, 延迟焦热解过程首先经历50~100 ℃的脱水阶段，较明显的失重从400 ℃开始，在620~640 ℃失重速率达到峰值，800 ℃之后快速失重，热失重速率不断增加。以三级化学反应模型模拟热解过程，在433~904 ℃的热解温度范围内，CO2气氛下的平均活化能为29.70~44.81 kJ/mol，Ar气氛下的平均活化能为57.68~69.44 kJ/mol。

STUDY ON THE THERMOGRAVIMETRIC ANALYSIS AND PYROLYSIS KINETICS OF COKE FROM DELAYED COKING

Pyrolysis of coke from delayed coking was performed by thermogravimetric analysis(TGA) in argon and carbon dioxide atmosphere from room temperature to 1 000 ℃ respectively.The mechanism of pyrolysis was discussed.TGA results showed that during the pyrolysis of coke dehydration happened at 50—100 ℃;then significant weight loss started from 400 ℃ and reached a maximum value around 620—640 ℃,which is commonly attributed to the release of volatile matter due to the rupture of side chains from organic compounds;above 800 ℃,weight loss increased remarkably,indicating rapid pyrolysis occurred.The average activation energy was determined using a third-order chemical reaction model to simulate the pyrolysis of coke from delayed coking.In the temperature range of 433—904 ℃,the average activation energy under CO2 and Ar atmosphere was 29.70—44.81 kJ/mol and 57.68—69.44 kJ/mol,respectively.