Biosynthesis of silver nanoparticles as catalyst by spent coffee ground/recycled poly(ethylene terephthalate) composites

摘要

Spent coffee ground (SCG) and poly(ethylene terephthalate) (PET) bottles are common wastes in the beverage industries. In this study, SCG and PET sheets from waste PET bottles were utilized to prepare PET/SCG composites. Those composites were embedded with silver nanoparticles (AgNPs) prepared from AgNO3 solutions (0-100 mM) without addition of catalyst or reducing agent, to be AgNPs@PET/SCG sheets. The generation of AgNPs was confirmed by field emission scanning electron microscopy (FESEM) and X-ray diffraction (XRD). According to inductively coupled plasma (ICP) analysis, the loaded amount of AgNPs on PET/SCGs was in the range of 0.9-7.3 mu g/cm(2). The catalytic performance and kinetics of AgNPs@PET/SCGs for the reduction of 4-nitrophenol with NaBH4 was studied, where 100% conversion can be reached in 20 min. The prepared AgNPs@PET/SCGs sheets allow easy separation from the reaction media, and can be reused for at least seven cycles while maintaining >90% conversion rate. The durable and reusable AgNPs@PET/SCGs made from waste materials may provide a promising alternative for further industrial applications. (C) 2020 Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.