Functionalized SiO(2) with N-, S-containing ligands for Pb(II) and Cd(II) adsorption
Φόρτωση...
Ημερομηνία
Συγγραφείς
Grigoropoulou, G.
Stathi, P.
Karakassides, M. A.
Louloudi, M.
Deligiannakis, Y.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
Elsevier
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
Colloids and Surfaces a-Physicochemical and Engineering Aspects
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
Five novel organosilicas SiO(2)-L have been prepared by grafting organic ligands (L) bearing thiazolidine (TAMS), thiazole (TIMS), imidazole (DTIMS), mercaptopropyl (DETATS) or pyridine (DETAPS) functional groups. The SiO(2)-L materials have been evaluated for their capacity for Pb(2+) and Cd(2+) uptake from aqueous solution as a function of the pH. The present data demonstrate that the grafting of the silica may result in significant enhancement of metal uptake by the SiO(2)-L adsorbent. Noticeably, multifunctional ligands such as DTIMS and DETAPS, have exhibited the highest metal capacity between the studied materials. Significant metal uptake was observed for both Pb and Cd on those materials independent of pH. The adsorption data have been analyzed based on a surface complexation model (SCM) with FITEQL by considering the grafted ligands as additional surface sites. FT-IR data are provided in support of this approach. Based on the theoretical speciation results, we may conclude that the determining factors for the metal uptake by the modified silica are the following three: (a) the presence or absence of protonable groups on the ligand determines the pH-edge profile, (b) the complexing affinity of the particular ligand towards each metal, and (c) the amount of grafted ligand on the silica surface. The interplay of these factors will determine the final maximum loading capacity of the sorbing material. Both the nature of the ligand as well as its surface concentration are of equal importance for the sorbing capacity of the material. (C) 2008 Elsevier B.V. All rights reserved.
Περιγραφή
Λέξεις-κλειδιά
modified sio(2), cd, pb, metal uptake, speciation, fiteql, surface complexation model, ft-ir, atomic-absorption-spectrometry, modified silica-gel, heavy-metal ions, aqueous-solution, thiol functionality, mesoporous silica, iron-oxide, surface, separation, hg(ii)
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000256871100005
http://ac.els-cdn.com/S0927775708000241/1-s2.0-S0927775708000241-main.pdf?_tid=2163425375823f93c06bdd7f4db13435&acdnat=1339492882_fafe6e54302cb71f06a9dc2d5b224d24
http://ac.els-cdn.com/S0927775708000241/1-s2.0-S0927775708000241-main.pdf?_tid=2163425375823f93c06bdd7f4db13435&acdnat=1339492882_fafe6e54302cb71f06a9dc2d5b224d24
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Μηχανικών Επιστήμης Υλικών