High Speed Sterilization of Water using Cellulose Grafted Membranes with Metallic Nanoparticles

Sinclair, Terica Raquel
Arruebo Gordo, Manuel (dir.)

Universidad de Zaragoza, CIEN, 2013

Master Erasmus Mundus en Ingeniería de Membranas

Resumen: The removal of bacteria and other organisms from water is an extremely important process, not only for drinking and sanitation but also industrially as bio-fouling is a commonplace and serious problem. This project presents a cellulose membrane filter grafted with silver nanoparticles for the high speed sterilization of water. In order to study the antimicrobial effects of silver nanoparticles, silver nano wires and nano spheres were synthesized , dispersed in water and characterized by Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) to reveal their formation and corresponding morphologies, dynamic light scattering (DLS) particle size analyser for particle size distribution, RadWag for concentration and finally Ultraviolet visible (UV-vis) scanning spectrophotoscopy to detect the distinct spectrum of the silver nanoparticles produced. These nanoparticles were then covalently bonded to commercially available cellulose filters, and functionalized by either thiol or amine groups. Followed by characterization by HR(S)-TEM, FE-SEM, energy-dispersive X-ray spectroscopy (EDXS), inductively coupled plasma atomic emission spectroscopy (ICP-AES), Attenuated total reflection Fourier-transform infrared (ATR FT-IR) to reveal that the cellulose membranes were effectively modified by the thiol or amine groups and highly loaded with well dispersed nanoparticles. As well as X-ray photoelectron spectroscopy (XPS) analysis was used showed that the nanoparticles were immobilized in the membrane by a stable covalent bond with the respective functional groups. The resulting cellulose-metal membranes were subjected to mechanical release testing, thus proving their robustness and suppression to release of the nanoparticles from their cellulose backbone. The metal cellulose filters showed high antimicrobial activity in excess of 99.9% growth inhibition against E. coli a member of the total coliform group. Thus we anticipate our filters with their high antibacterial property and durability can be produced in a cost effective manner and if developed is capable of producing affordable, clean and safe drinking water.

Tipo de Trabajo Académico: Trabajo Fin de Master