Abstract Methanol-mixed fuels consisting of methanol, propane, and a small amount of auxiliary solvent are widely used as inexpensive industrial fuels, but the carbon deposition in the pyrolysis of this fuel seriously restrains its popularization. This paper studied the characteristics of gaseous products and carbon deposition in the pure propane and methanol-propane mixture pyrolysis experimentally, analyzed the effect of methanol addition on the reaction path of propane pyrolysis and production rate of key species by using detailed reaction mechanism. Results show that methanol addition can restrain C2H4 converting to C2H2 in the later stage of pyrolysis. The carbon deposition rate and particle diameter increase exponentially with the increase of reaction temperature in both pure propane and methanol-propane blend pyrolysis. Methanol addition can significantly reduce the carbon deposition rate and particle diameter. The reaction path analysis indicates that the main reaction paths forming benzene are C3H3 → A1 and C4H4 → I-C6H6 → A1, and C3H3 is a key specie to form benzene. The pyrolysis of methanol-propane mixture generates more H2 and H than that of pure propane pyrolysis, which makes most C3H6 convert to C2H4, reduces the amount of C3H3 and suppresses the conversion of C2H4 to C2H2. And then the amount of benzene is reduced significantly and the generation of subsequent PAHs and carbon deposition is inhibited. Lots of H2 also restrains the hydrogen abstraction from benzene resulting in the delay of the formation of PAHs and carbon deposition. This study is of great significance to research the soot formation in hydrocarbon combustion with alcohol fuel.

中文翻译：

---

添加甲醇对丙烷热解积炭的抑制作用

摘要 由甲醇、丙烷和少量辅助溶剂组成的甲醇混合燃料作为廉价的工业燃料被广泛使用，但这种燃料热解过程中的积碳严重制约了其推广应用。本文通过实验研究了纯丙烷和甲醇-丙烷混合物热解中气态产物和积炭的特征，通过详细的反应机理分析了甲醇添加对丙烷热解反应路径和关键物种产率的影响。结果表明，甲醇的加入可以抑制C2H4在热解后期转化为C2H2。在纯丙烷和甲醇-丙烷共混热解中，碳沉积速率和颗粒直径随着反应温度的增加呈指数增加。添加甲醇可以显着降低积碳速度和颗粒直径。反应路径分析表明，形成苯的主要反应路径为C3H3→A1和C4H4→I-C6H6→A1，C3H3是形成苯的关键物质。甲醇-丙烷混合物的热解比纯丙烷热解产生更多的H2和H，这使得大部分C3H6转化为C2H4，减少了C3H3的量并抑制了C2H4向C2H2的转化。然后苯的量显着减少，并抑制了后续多环芳烃的产生和积碳。大量的 H2 还抑制了从苯中提取氢，从而延迟了 PAHs 的形成和碳沉积。该研究对研究醇类燃料碳氢化合物燃烧的烟尘形成具有重要意义。