Selective Oxidation of H 2 S to Elemental Sulfur over Waste PET-Derived Biochar-Supported Metal Catalysts
Year: 2025
Type: article
Abstract: High Resolution Image Download MS PowerPoint Slide The upcycling of plastic waste into high-value functional materials offers a sustainable pathway aligned with green chemistry and circular economy principles. In this study, activated carbon (aPAC) was synthesized from waste PET bottles via KOH activation and employed as a support for trivalent metal catalysts (Fe, Bi, and Ce) aimed at low-temperature catalytic oxidation of hydrogen sulfide (H 2 S). Among the prepared catalysts, Fe/aPAC exhibited the most promising performance, achieving nearly complete H 2 S conversion (∼95%) and a high sulfur yield (∼90%) under humid air at 30 °C. Textural and surface characterizations (X-ray diffraction, Fourier transform infrared, X-ray photoelectron spectroscopy, CO 2 -temperature-programmed desorption, and scanning electron microscopy [SEM]/EDS) revealed that the presence of Fe 2 O 3 /FeOOH, abundant oxygenated groups (C–O, C─O, O–H), and surface basicity collectively enhanced redox activity and H 2 S adsorption. Notably, the catalyst maintained over 80% conversion after three regeneration cycles, demonstrating excellent stability and reusability. Extracted sulfur products were confirmed via SEM and visible recovery. A reaction mechanism involving H 2 S dissociation, Fe 3+ /Fe 2+ redox cycling, and surface-assisted O 2 activation was proposed. This work not only provides mechanistic insights into H 2 S oxidation under mild conditions but also proposes a cost-effective and scalable approach for converting PET waste into efficient catalytic materials, offering dual environmental benefits in sulfur recovery and plastic valorization.
Source: ACS Omega
Authors: Jia-Yin Lin, Guan-Jie Wang, Jia-Yu Lee, Yu-Lun Wu, Chih-Ying Wang
Institution: National Chung Hsing University
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: gold
Estimated APC paid: $1,935
OpenAlex ID: W7110077304