Molecular dynamics study on hydrogen production from supercritical water decomposition of Polyethylene terephthalate

Abstract

Polyethylene terephthalate (PET) is widely used in packaging, electronics, and synthetic fibers. Due to the need for adequate recycling methods, it leads to environmental pollution. Exploring new efficient PET degradation technologies is particularly important. As an efficient and clean method for treating synthetic polymers, supercritical water gasification (SCWG) technology has broad application prospects. In this paper, PET was modeled using Materials Studio software, and a supercritical water reaction system was established. The detailed mechanism of PET decomposition in supercritical water was studied using reactive molecular dynamics simulations. The effects of different operating conditions on the gasification products were analyzed. The results show that higher temperatures help increase the hydrogen yield, while high feedstock concentrations are not conducive to hydrogen production. Additionally, the decomposition pathways of PET were analyzed based on the reaction routes. This provides an effective method for polymer degradation and has significant implications for optimizing hydrogen production through SCWG.