Pyrolysis is a potential approach to treat post-consumer waste natural rubber (NR), however, unclear pyrolysis mechanism restricts its actual utilization. In this work, thermal degradation of NR was investigated combining dynamical method with pyrolysis on the infrared-heating fixed-bed reactor. Results show that thermal degradation of NR is an apparently exothermic and multistep reaction, tar yield reaches up to 96.59 wt%. Pyrolysis tar mainly consists of cycloolefin with a small quantity of chain olefins and mono-ring aromatic hydrocarbons. High temperature reduces the cycloolefin yield but promotes the generation of mono-ring aromatic hydrocarbons. Tar is mainly composed of dimer (C10) or trimer (C15) of isoprene with different structures. H type in tar is mainly aliphatic hydrogen. Besides, a possible pyrolysis mechanism based on the β bond breakage was proposed. The work can provide a theoretical basis for direct control of high value-added products during NR pyrolysis and achieve high efficiency pyrolysis of NR.

中文翻译：

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红外快速加热固定床结合热解动力学深入研究天然橡胶热解特性及机理


热解是处理消费后废弃天然橡胶（NR）的一种潜在方法，然而，不清楚的热解机制限制了其实际利用。本工作将动态方法与红外加热固定床反应器上的热解相结合，研究了天然橡胶的热降解。结果表明，天然橡胶的热降解是一个明显放热的多步反应，焦油产率高达96.59 wt%。热解焦油主要由环烯烃及少量链烯烃和单环芳烃组成。高温降低了环烯烃收率，但促进了单环芳烃的生成。焦油主要由不同结构的异戊二烯二聚体（C10）或三聚体（C15）组成。焦油中的H型主要是脂肪族氢。此外，还提出了一种基于β键断裂的可能热解机制。该工作可为天然橡胶热解过程中高附加值产物的直接控制提供理论依据，实现天然橡胶的高效热解。