Highly Efficient and Rapid Cs+ Uptake by the Layered Metal Sulfide K2xMnxSn3-xS6 (KMS-1)
Φόρτωση...
Ημερομηνία
Συγγραφείς
Manos, M. J.
Kanatzidis, M. G.
Τίτλος Εφημερίδας
Περιοδικό ISSN
Τίτλος τόμου
Εκδότης
American Chemical Society
Περίληψη
Τύπος
Είδος δημοσίευσης σε συνέδριο
Είδος περιοδικού
peer reviewed
Είδος εκπαιδευτικού υλικού
Όνομα συνεδρίου
Όνομα περιοδικού
J Am Chem Soc
Όνομα βιβλίου
Σειρά βιβλίου
Έκδοση βιβλίου
Συμπληρωματικός/δευτερεύων τίτλος
Περιγραφή
The details of the ion-exchange properties of the layered sulfide material K2xMnxSn3-xS6 (x = 0.5-0.95) (KMS-1) with Cs+ and Rb+ cations are reported. X-ray photoelectron spectroscopy (XPS), elemental analyses, and powder and single-crystal diffraction studies revealed that the Cs+ and Rb+ ion exchange of KMS-1 is complete (quantitative replacement of K+ ions) and topotactic. These data also revealed that the Cs+ exchange is accompanied with a rare topotactic oxidation of Mn2+ to Mn3+ caused by atmospheric oxygen, while the Rb+ ion exchange only slightly alters the oxidation state of the layer manganese atoms. The absorption of Cs+ by KMS-1 follows the Langmuir model with a high exchange capacity of 226(4) mg/g (pH approximate to 7) and distribution coefficients as high as 2 x 10(4) mL/g. KMS-1 displays significant cesium uptake both under strongly acidic (pH 0.7-2.6) or basic conditions (pH 10-12). The kinetics of Cs+ capture by KMS-1 is fast (>90% removal of similar to 1 ppm of Cs+ within only 5 min). KMS-1 was also found capable to efficiently absorb Cs+ from complex solutions containing various competitive cations in large excess. KMS-1 (containing Mn3+ ions) can be regenerated and reused for Cs+ exchange with an exchange capacity very similar to that of the pristine KMS-1. The results indicate that layered metal sulfides with ion-exchange properties may be considered as highly selective and cost-effective sorbents for remediation of water contaminated with the radioactive Cs-137 isotope. The selectivity over other alkali ions for Cs originates not from a size effect but from the more favorable Cs center dot center dot center dot S soft Lewis acid/Lewis base interactions.
Περιγραφή
Λέξεις-κλειδιά
intercalation compounds, double hydroxide, ion-exchangers, intrinsic disorder, strontium removal, nanocomposites, adsorption, clay, chemistry, cesium
Θεματική κατηγορία
Παραπομπή
Σύνδεσμος
<Go to ISI>://000265939200062
http://pubs.acs.org/doi/pdfplus/10.1021/ja900977p
http://pubs.acs.org/doi/pdfplus/10.1021/ja900977p
Γλώσσα
en
Εκδίδον τμήμα/τομέας
Όνομα επιβλέποντος
Εξεταστική επιτροπή
Γενική Περιγραφή / Σχόλια
Ίδρυμα και Σχολή/Τμήμα του υποβάλλοντος
Πανεπιστήμιο Ιωαννίνων. Σχολή Θετικών Επιστημών. Τμήμα Χημείας