TITLE:
Geosmin Sorption on Cyclodextrin Polymers
AUTHORS:
Redel Gutierrez, Niwooti Whangchai, Nakao Nomura
KEYWORDS:
Geosmin; Cyclodextrin Polymers; Water; Sorption Kinetics
JOURNAL NAME:
International Journal of Geosciences,
Vol.4 No.5B,
October
11,
2013
ABSTRACT: Geosmin is one of the major causative compounds of
earthy-musty odor and taste (off-flavor) in drinking water (lakes) and in
farmed fish. In this study, the sorption of cyclodextrin polymers (CDPs)
towards geosmin in aqueous solution was investigated. Sorption kinetics, the
effect of solution pH and contact time on the sorption capability of α-, β- and γ-cyclodextrin polymers was discussed.
Results disclosed that the sorption of geosmin by the CDPs followed the Ho and
McKay kinetic mechanism with the liquid film diffusion as the rate-determining
step. Both β-CDP and γ-CDP exhibit high removal efficiencies
of 93.4% and 96%, respectively, within 240 minutes at 25°C and pH 7, whilst α-CDP was not effective, removing only
40% geosmin, at an initial concentration of 5 μg·L—1and 5 g·L—1of CDP dose. The cyclodextrin polymers can adapt to a wide range of pH from 3.0
to 11.0 for geosmin adsorption with pH 7.0 as optimum. Results indicate that
these sorbents demonstrate significant potential in reducing the concentration
of geosmin in water that presents taint problems in both drinking water and
fish.