Introduction

This chapter examines the urgent need for rational methods to address plastic waste, focusing on polyethylene terephthalate (PET), which accounts for 8% of global plastic production and has significant environmental impacts. Current methods like landfill and incineration cause soil pollution and greenhouse gas emissions, while mechanical recycling often results in rPET with reduced properties. Chemical reforming emerges as a promising solution, capable of producing high-value products and preserving PET's original properties. This process involves converting waste PET into monomers through methods like glycolysis, methanolysis, and hydrolysis, and further upcycling into valuable chemicals via thermal, electrocatalytic, and photocatalytic reforming. The chapter explores emerging strategies such as photothermal and photo-electrocatalytic reforming, providing a comprehensive overview of chemical reforming methods and their potential to address PET waste sustainably. It begins with a chronological overview of key developments, from Zhang et al.'s (2013) introduction of phase transfer catalysts to recent advancements like selective electrocatalytic reforming and thermal processes. The chapter also compares advanced photo-driven/assisted reforming systems with traditional methods, highlighting their advantages.