(177ag) Exploring the Mechanism and Potential of Polystyrene-Zeolites Co-Pyrolysis System for Enhancing Styrene Recycling: A Molecule Dynamics Study

To help address the urgent challenge of polystyrene (PS) waste, our study employs an integrated computational approach that combines Monte Carlo simulations, reactive molecular dynamics (MD) simulations, and machine learning to explore the co-pyrolysis of PS with zeolites. By delving into the intricate reaction mechanisms and the influence of zeolites, we uncovered that a chain-breaking mechanism predominantly facilitates PS degradation. We identified styrene and alpha-methyl styrene (AMS) as the major products, and the yield of styrene can be interestingly significantly amplified in the presence of zeolites and through a multi-step screening process that explores the selectivity of styrene over AMS with the interface models of the PS adsorbed on the different zeolite surfaces. It is noted that zeolite structures that markedly enhance the pyrolysis selectivity and efficiency, particularly favoring the yield of styrene while reducing side products, were selected. Our investigations also reveal that the actions of zeolites, driven by the adsorption behaviors of PS polymers on their surfaces and the subsequent styrene adsorption within their frameworks, are pivotal in optimizing the pyrolysis process. This nuanced understanding not only paves the way for developing novel, sustainable recycling methods but also contributes to a broader application of similar computational techniques for environmental management challenges.

The study advances an efficient framework for PS-zeolite co-pyrolysis, significantly contributing to sustainable waste management efforts. The integration of Monte Carlo calculations and ReaxFF simulations, enriched by machine learning insights, elucidates the effects of zeolites in detail. It highlights the critical role of zeolite selection, through rigorous screening, in targeting enhanced selectivity towards valuable hydrocarbons. This holistic view of the PS-zeolite co-pyrolysis system emphasizes the transformative potential of zeolite catalysis in achieving improved product yields. By presenting a model for the chemical recycling of plastic waste, our research establishes a solid foundation for future investigations and underscores the significance of sophisticated computational approaches in tackling polymer simulation and environmental sustainability issues.