naa a22 4500 51082093X CHVBK 20180411083531.0 cr unu---uuuuu 180411e20130801xx s 000 0 eng 10.1007/s11814-013-0077-9 doi (NATIONALLICENCE)springer-10.1007/s11814-013-0077-9 Silica nanoparticles modified with a Schiff base ligand: An efficient adsorbent for Th(IV), U(VI) and Eu(III) ions [Elektronische Daten] [Zahra Shiri-Yekta, Mohammad Yaftian, Abdolreza Nilchi] Modification of SiO2 nanoparticles by salicylaldiminepropyl results in efficient adsorbents for removal of Th4+, UO 2 2+ and Eu3+ ions from aqueous solutions. The effect of parameters influencing the adsorption efficiency such as aqueous phase pH, contact time, initial metal ions concentration, adsorbent dosage and temperature dependency of the process was verified and discussed. Under optimal conditions (pH 5.5, adsorbent dosage 0.05 g, contact time 30 min. and 25 °C), thorium and uranyl ions (initial concentration 20 mg/l) were quantitatively removed from 20 ml of sample solution. Under such conditions 85% of europium ions was removed. Comparison of the adsorption efficiency of the studied modified nano-particles with those unmodified ones shows a shift for uptake of the metal ions vs. pH curves towards lower pH values by applying the modified adsorbents. In addition, a significant improvement of europium ions adsorption was observed by using the modified nanoparticles. Kinetics of the process was studied by considering a pseudo second-order model. This model predicts chemisorption for the adsorption mechanism. Freundlich, Langmuir and Temkin models were suitable for describing the equilibrium data of Th4+, UO2 2+ and Eu3+ adsorption process, respectively. Thermodynamic investigation reveals the adsorption process of the studied ions is entropy driven. Korean Institute of Chemical Engineers, Seoul, Korea, 2013 Modified Silica Nano-particles nationallicence Schiff Base nationallicence Th(IV) nationallicence U(VI) nationallicence Eu(III) nationallicence Removal nationallicence Separation nationallicence Shiri-Yekta Zahra Phase Equilibria Research Laboratory, Department of Chemistry, Faculty of Science, University of Zanjan, P. O. Box 45371-38791, Zanjan, Iran aut Yaftian Mohammad Phase Equilibria Research Laboratory, Department of Chemistry, Faculty of Science, University of Zanjan, P. O. Box 45371-38791, Zanjan, Iran aut Nilchi Abdolreza Jaber Ibn Hayan Research Laboratories of Iran, P. O. Box 11365-8486, Tehran, Iran aut Korean Journal of Chemical Engineering Springer US; http://www.springer-ny.com 30/8(2013-08-01), 1644-1651 0256-1115 30:8<1644 2013 30 11814 https://doi.org/10.1007/s11814-013-0077-9 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11814-013-0077-9 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shiri-Yekta Zahra Phase Equilibria Research Laboratory, Department of Chemistry, Faculty of Science, University of Zanjan, P. O. Box 45371-38791, Zanjan, Iran aut NATIONALLICENCE 700 1- Yaftian Mohammad Phase Equilibria Research Laboratory, Department of Chemistry, Faculty of Science, University of Zanjan, P. O. Box 45371-38791, Zanjan, Iran aut NATIONALLICENCE 700 1- Nilchi Abdolreza Jaber Ibn Hayan Research Laboratories of Iran, P. O. Box 11365-8486, Tehran, Iran aut NATIONALLICENCE 773 0- Korean Journal of Chemical Engineering Springer US; http://www.springer-ny.com 30/8(2013-08-01), 1644-1651 0256-1115 30:8<1644 2013 30 11814 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer