APPLICATION OF MAGNETIC NANOPARTICLES IN DRINKING WATER PURIFICATIONAutori: Yunfeng Xu
Data aparitiei: August / 2014
Revista: Environmental Engineering and Management Journal › Vol. 13 › Nr. 8
ISSN: 1843 - 3707
Pathogenic bacteria are fetal to human health, requiring cost-effective and safe approaches to be removed from drinking water
source. With poly-allylamine-hydrochloride (PAAH) stabilization, magnetic nanoparticles (MNPs) were introduced in this study
to remove pathogenic bacteria by electrostatic interaction and magnet capture. High removal efficiency was achieved for four
main pathogenic species, as Escherichia, Acinetobacter, Pseudomonas and Bacillus, and over 99.5% of the pathogens can be
removed when the bacterial count was less than 105 CFU/mL. Related to various species, the MNPs have respective adhesion
effects on bacterial cells, which are higher for Acinetobacter and Pseudomonas, due to the mechanisms of external cell structure
and ion exchange capacity, but not the zeta potential of bacterial cell surface. With the practical application in real drinking water
samples collected from reservoirs in Sheffield and Leeds, the results showed high bacteria removal efficiency (99.48%) and the
total bacteria residual counts was as low as 78 CFU/mL, which met the drinking water standard of WHO (<100 CFU/mL).
Further toxicity test indicated that no significant genotoxicity or cytoxicity existed in MNPs treated water, suggesting MNPs are
biocompatible for safety issues in drinking water. As an effective, easy-operation and low cost technique, MNPs have bright
future and great potential in practical drinking water treatment to remove pathogenic bacteria.