Please use this identifier to cite or link to this item: http://hdl.handle.net/1959.13/43274

OpenURL Link
Title
The effect of ozonation on aggregation of humic substances on mica studied by atomic force microscopy
Author/Creator
Donose, Bogdan C.;  Nguyen, Anh V.;  Evans, Geoffrey M.;  Yan, Yaode
Institution
The University of Newcastle. Faculty of Engineering & Built Environment, School of Engineering
Description
Humic substances influence adsorption and aggregation of colloids and ions in natural aquatic environment and thereby affect drinking water treatment by ozonation. In this paper the effect of ozonation on the ability of humic substances to form supramolecular structures was investigated by atomic force microscopy(AFM) surface topography. Ozonated and unozonated solutions of Suwannee River humic acid and fulvic acid were deposited onto molecularly smooth mica surfaces, left to dry and then imaged by AFM in non-contact mode. Two solutions with pH 4 and pH 7 were investigated. At each pH, significant differences in the aggregation behavior between these humic substances before and after ozonation were observed. In particular, ozonation increased the aggregate size of fulvic acid at the neutral pH. Size exclusion chromatography also revealed similar molecular weight distributions for the humic substances after ozonation. It was argued that difference in the molecular hydrophobicity or factors other than molecular weight could be responsible for the observed aggregation behavior. The outcome of this study is important for a better understanding of supramolecular structures of humic substances in ozonation, particularly those in drinking water treatment.
Relation
Colloids and Surfaces A: Physicochemical and Engineering Aspects Vol. 329, Issue 1-2, p. 100-105
Publisher Link
http://dx.doi.org/10.1016/j.colsurfa.2008.06.054
Date
2008
Publisher
Elsevier
Keyword(s)
humic substances;  ozonation;  aggregation;  atomic force microscopy
Resource Type
journal article
Identifier
http://hdl.handle.net/1959.13/43274
Identifier
ISSN:0927-7757
Reviewed
Reviewed
16 Visitors 17 Hits 0 Downloads
Save/E-mail Citation
Citation Format
E-mail Address
Subject
"Colloids and Surfaces A: Physicochemical and Engineering Aspects"
 
OR