abstract
Microporous silicate Eu-AV-20 has recently proved to be a promising ion exchange material for cesium removal from aqueous solutions, and its potential for Cs+ photoluminescence sensing was additionally demonstrated. In this work, Cs+ removal was performed in a fixed-bed column, and the influence of linear velocity and mass of ion exchanger on the breakthrough curves was analysed. The experimental data were modelled on the basis of Nernst-Planck (NP) equations and with four well-known analytic models. The analytic expressions provided low errors (root mean square deviation, RMSD, between 3.20% and 6.47%); the 2-parameter NP-based model fitted the data quite well (RMSD = 6.66% for correlation and 6.54% for prediction), yielding crucial information on both the transport mechanism within the Eu-AV-20 particles, and the intrinsic dynamic behaviour of the fixed-bed ion exchange column. Taking into account that Eu-AV-20 samples loaded with different amounts of Cs+ exhibited distinct photoluminescence spectra, our results reinforce the potential of AV-20 materials for Cs+ sensing, which raises the possibility of online monitoring the ion exchange in a fixed-bed column using an optical fibre and a spectrometer. (C) 2015 Elsevier B.V. All rights reserved.
keywords
CESIUM ION-EXCHANGE; TITANOSILICATE ETS-4; AQUEOUS-SOLUTIONS; CRYSTALLINE SILICOTITANATE; CHELATING RESIN; HG2+ IONS; MECHANISM; ZEOLITE; BATCH; WATER
subject category
Engineering
authors
Figueiredo, BR; de Melo, MMR; Portugal, I; Ananias, D; Rocha, J; Silva, CM
our authors
Bruno Reis Figueiredo
PhD Student
Carlos Manuel Silva
Associate Professor
Duarte Ananias
Assistant Researcher
Inês Portugal
Assistant Professor
João Rocha
Full Professor
Marcelo Morais Rodrigues de Melo
Post-Doc Fellowshipacknowledgements
B.R. Figueiredo acknowledges a Ph.D. Grant from Fundacao para a Ciencia e a Tecnologia (SFRH/BD/75457/2010). This work was developed in the scope of the project CICECO-Aveiro Institute of Materials (Ref. FCT UID/CTM/50011/2013), financed by national funds through the FCT/MEC and when applicable co-financed by FEDER under the PT2020 Partnership Agreement.