A hypothetical approach toward laser-induced high-density polyethylene pyrolysis: a review

Abstract

Laser-induced breakdown spectroscopy (LIBS) is a commonly employed technique in commercial plastic recycling for purposes including classification, sorting, identification, and elemental analysis. However, understanding the molecular-level kinetics, thermodynamic interactions, bonding cleavage, and process parameter impacts is crucial for identifying necessary modifications to enhance plastic recycling. A review of the literature revealed that LIBS can also facilitate plastic pyrolysis, a significant research area that remains largely unexplored. Based on theoretical hypotheses, it can be concluded that laser-induced pyrolysis may offer advantages over traditional pyrolysis, which requires understanding the chemistry of plastic bond-breaking during degradation, identifying resistant bonds, and uncovering the root causes of these challenges. This approach is described in detail in sections 9 and 10, focusing on high-density polyethylene (HDPE) under controlled conditions. The identified research gaps could be further investigated, and advancements could be made toward establishing efficient plastic recycling and designing laser-induced pyrolysis reactors.