关键词: 轮胎橡胶, 分子动力学, 热解, 废物处理

Abstract:

In order to further understand the pyrolysis mechanism of tire rubber, the molecular dynamics method was used to simulate the pyrolysis process of tire rubber, and the reaction paths of gas-phase products were speculated by combining the simulation results and density function. The simulation results showed that the pyrolysis process was mainly divided into two stages: the low temperature pyrolysis stage where the main reaction was the long chain fracture of rubber to form monomers and the main products were isoprene, styrene and 1,3-butadiene, and the high temperature pyrolysis stage where the main reaction was that the monomers further generated small molecular gas in which CH₄, H₂ and C₂H₄ accounted for the majority with a small amount of C₂H₆ and C₃H₆. Among them, CH₃· attacking isoprene and styrene monomer to capture the H· at a specific position was the optimal path to generate CH₄, H· attacking styrene monomer to capture the H· at a specific position was the optimal path to generate H₂ and CH₂CH· attacking 1,3-butadiene monomer to capture the H· at a specific position was the optimal path to generate CH₂CH₂. The pyrolysis products were compared with those of natural rubber alone and natural rubber/butadiene styrene rubber co-pyrolysis. This would provide a theoretical basis for pyrolysis of waste tire rubber to obtain specific gaseous products and catalytic pyrolysis.

Key words: tyre rubber, molecular dynamics, pyrolysis, waste treatment