Methane generation from oil cracking: Kinetics of 9-methylphenanthrene cracking and comparison with other pure compounds and oil fractions
Methane generation from oil cracking: Kinetics of 9-methylphenanthrene cracking and comparison with other pure compounds and oil fractions
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DOI：
10.1021/ef980164p
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发表时间：
1999-03-01
期刊：
影响因子：
5.3
通讯作者：
Tang, Y
中科院分区：
文献类型：
--
作者：
Behar, F;Budzinski, H;Tang, Y
该研究的目的是确定在 120 bar 恒定压力下 375-450 摄氏度温度范围内 9-甲基菲 (9-MPh) 热裂解产生甲烷的表观归宿常数，以通过外推法评估地质条件下原油甲基化芳烃的热稳定性。第一步，仅基于 9-MPh 的转化，确定速率常数并鉴定生成的产物：将总体动力学方案与 L-甲基芘热裂解文献中提出的方案进行比较（Smith, C. M.；Savage, P. E. Energy Fuels 1992, 6, 195-202）。然后对 9 MPh 的一次和二次裂解过程中产生的甲烷进行定量，并确定其产生的相应表观速率常数。 9-MPh 降解的表观动力学参数 E 为 49.0 kcal/mol，A 为 4.5 x 10(10) s(-1)，而产生甲烷的 E 为 54.5 kcal/mol，A 为 1.1 x 10(12) s(-1)。当这些结果外推到地质条件（T < 200 摄氏度）时，对应于两个反应的阿累尼乌斯图与实验室和地质条件之间的 n-C-25 反应交叉。因此，甲基化化合物的早期转化和后期甲烷的产生都将在正烷烃发生显着裂解之前发生。还将 9-MPh 的热裂解与在封闭热解系统中代表有机质主要类型（I、II 和 PPI）的干酪根人工成熟过程中产生的甲基化芳烃的集总化学类别进行了比较。
The aim of the study is to determine the apparent fate constants for methane generation from the 9-methylphenanthrene (9-MPh) thermal cracking in the temperature range 375-450 degrees C under a constant pressure of 120 bar to evaluate by extrapolation the thermal stability of methylated aromatics of crude oils in geological conditions. In the first step, based on the conversion of 9-MPh only, rate constants were determined and the generated products were identified: the overall kinetic scheme was compared to that proposed in the literature for the l-methylpyrene thermal cracking (Smith, C. M.; Savage, P. E. Energy Fuels 1992, 6, 195-202). Then the methane generated during primary and secondary cracking of 9-MPh was quantified, and the corresponding apparent rate constants for its production were determined. The apparent kinetic parameters for the degradation of 9-MPh are 49.0 kcal/mol for E and 4.5 x 10(10) s(-1) for A, whereas E is 54.5 kcal/mol and A is 1.1 x 10(12) s(-1) for methane generation. When these results are extrapolated to geological conditions (T < 200 degrees C), the Arrhenius diagrams corresponding to the two reactions cross that of n-C-25 between laboratory and geological conditions. Consequently, both the early transformation of the methylated compounds and the late methane production will take place before the occurrence of a significant cracking of the n-alkanes. The thermal cracking of 9-MPh was also compared to that of the lumped chemical class of methylated aromatics generated during artificial maturation of kerogens representative of the main types of organic matter (I, II, and PPI) in closed pyrolysis systems.