An extensive literature review of the mechanistic modeling of n-heptane and cyclohexane pyrolysis was carried out. It was shown that Rice–Kossiakoff free radical theory does not adequately account for product distributions of n-heptane pyrolysis in the high conversion regime. Secondary reactions of alpha higher olefins and di-olefins accounted for the major products (ethene, propene and 1-butene) of n-heptane pyrolysis. Predicted product distributions (CH₄, C₂H₄, C₃H₆, 1-C₄H₈ and 1,3-C₄H₆) of n-heptane pyrolysis showed very good agreement with experimental data. The product distributions of cyclohexane pyrolysis in the high conversion regime were rationalized and adequately accounted for using decomposition reactions of cyclohexyl bi-radicals followed by secondary reactions of major primary products such as C₃H₆ and 1,3-C₄H₆. The latter expanded mechanism can be used to model cyclohexane pyrolysis in the high conversion regime. Rate parameters (pre-exponential factors and activation energy) for each of the elementary reactions of n-heptane mechanistic model were either obtained from the literature or estimated using thermochemical parameters. The use of steady state approximation in mathematical modeling of n-heptane pyrolysis led to erroneous results.

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正庚烷和环己烷热解的机理和数学模型综述

对正庚烷和环己烷热解机理进行了广泛的文献综述。研究表明，赖斯-科西亚科夫自由基理论不能充分解释高转化率条件下正庚烷热解产物的分布。α-高级烯烃和二烯烃的副反应是正庚烷热解的主要产物（乙烯，丙烯和1-丁烯）。预测的产物分布（CH ₄，C ₂ H ^ ₄，C ₃ H ^ ₆，1-C ₄ H ^ ₈和1,3--C ₄ H ^ ₆）的Ñ庚烷热解表明与实验数据非常吻合。在高转化率条件下，对环己烷热解产物的分布进行了合理化处理，并充分利用了环己基双基团的分解反应，接着进行了主要初级产物（例如C ₃ H ₆和1,3-C ₄ H _6）的次级反应来进行适当解释。后者的扩展机理可用于模拟高转化率条件下的环己烷热解。n的每个基本反应的速率参数（指数前因子和活化能）-庚烷机理模型可以从文献中获得或使用热化学参数进行估算。在正庚烷热解数学模型中使用稳态近似会导致错误的结果。