title: Fluorescence labelling as tool for zeolite particle tracking in nanoremediation approaches.
abstract: Colloidal Fe-zeolites such as Fe-BEA-35 are currently under study as new adsorbent and catalyst materials for in-situ chemical oxidation with H2O2. As for nanoremediation in general, the availability of suitable particle detection methods is a requirement for successful process development and particle tracing. Detection and distinguishing between natural colloids and introduced particles with a similar composition are a challenge. By means of fluorescence labelling, a highly specific detection option for Fe-BEA-35 was developed. 'Ship-in-a-bottle' synthesis of fluorescein within the zeolite pores, which was applied for the first time for a BEA type zeolite, provides a product with stable and non-extractable fluorescence. When the fluorescent labelled zeolite is added at a concentration of 1wt.% referring to the total zeolite mass, a very low detection limit of 1mg/L of total zeolite is obtained. Compared to commonly applied turbidity measurements, detection via fluorescence labelling is much more specific and sensitive. Fluorescence is only marginally affected by carboxymethyl cellulose, which is frequently applied as stabilizer in application suspensions but will be depleted upon contact with H2O2. Transport properties of fluorescent labelled and non-labelled Fe-zeolite particles are in agreement as determined in a column study with quartz sand and synthetic groundwater (classified as very hard).
authors: Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Engineering, Permoserstrasse 15, D-04318 Leipzig, Germany.
authors: Glenn
authors: G
authors: Gillies
authors: Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Engineering, Permoserstrasse 15, D-04318 Leipzig, Germany.
authors: Katrin
authors: K
authors: Mackenzie
authors: Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Engineering, Permoserstrasse 15, D-04318 Leipzig, Germany.
authors: Frank-Dieter
authors: FD
authors: Kopinke
authors: Helmholtz Centre for Environmental Research - UFZ, Department of Environmental Engineering, Permoserstrasse 15, D-04318 Leipzig, Germany.
authors: Anett
authors: A
authors: Georgi
keywords: Fe-zeolites; Fluorescence labelling; Nanoremediation; Particle detection; Particle tracking; Ship-in-a-bottle