Green cellulose-based adsorbent as an effective PFAS sampling tool

• Main Author: Lim, Kang Brian
• Other Authors: Dalton Tay Chor Yong
• Format: Final Year Project
• Language: English
• Published: Nanyang Technological University 2023
• Subjects: Engineering::Materials
• Online Access: https://hdl.handle.net/10356/167142
• Institution: Nanyang Technological University

The development of efficient, sustainable sorbents with high reusability is a key issue in PFAS removal from water. This project aims to develop an amine-functionalised cellulose adsorbent with magnetic properties to facilitate reusability and enhance adsorption. Increasing amounts of polyethylenimine were grafted onto cellulose nanofibrils to improve the overall surface functionalisation while adding adsorption sites. They were then characterised by elemental analysis, acid base titration, fourier transform infrared (FT-IR) spectroscopy, transmission electron microscopy and scanning electron microscopy to determine the most optimal ratio. Thereafter, silica coated ferrous magnetic nanoparticles are synthesised and functionalised with amine groups to facilitate grafting to the amine-functionalised cellulose product, thus providing the magnetic properties for reuptake. The final product was synthesised with increasing amounts of amine functionalised magnetic nanoparticles, and characterised with the techniques mentioned before, along with vibrating-sample magnetometer (VSM) analysis to determine the optimal ratio. A 2:1 mass ratio of polyethylenimine to cellulose nanofibrils was determined to provide the most amine loading among the synthesised formulations, while a 1:1 mass ratio of amine functionalised magnetic nanoparticles to the 2:1 polyethylenimine:cellulose nanofibrils ratio was ascertained to provide the most amine group loading and saturation magnetism.