Synthesis of Porous Carbons from the Valorization of Polyethylene Terephthalate Waste

Abstract

Upcycling plastic waste for water remediation is a promising paradigm for enabling a circular economy. This study aimed at investigating the synthesis of porous carbons from waste polyethylene terephthalate (PET) bottles using potassium hydroxide and zinc chloride as activating agents at temperatures ranging from 700 to 800°C. The influence of different activating agents and activation temperatures on the characteristics of porous carbons was investigated. The morphological and structural characteristics of the resultant porous carbons were analyzed using scanning electron microscopy (SEM), Raman spectroscopy, and nitrogen physisorption surface area analysis. The SEM data revealed interconnected porous morphologies for all the porous carbons obtained. Raman spectra showed two distinct D and G bands at 1336-1347 cm⁻¹ and 1587-1599 cm⁻¹, respectively, indicating carbon graphitic structures. The ID/IG ratios revealed varying degrees of graphitization depending on the activation agent and temperature. The highest surface area obtained was 289 m²g⁻¹ at 800°C with porous carbons synthesized using KOH as the activating agent. This study demonstrates that waste PET is a viable and sustainable precursor for fabricating porous carbons.