TY - JOUR AU - Klencsár, Zoltán AU - Köntös, Zoltán TI - EPR Analysis of Fe3+ and Mn2+ Complexation Sites in Fulvic Acid Extracted from Lignite JF - JOURNAL OF PHYSICAL CHEMISTRY A J2 - J PHYS CHEM A VL - 122 PY - 2018 IS - 12 SP - 3190 EP - 3203 PG - 14 SN - 1089-5639 DO - 10.1021/acs.jpca.8b00477 UR - https://m2.mtmt.hu/api/publication/30388793 ID - 30388793 N1 - Cited By :19 Export Date: 30 June 2023 CODEN: JPCAF Correspondence Address: Klencsár, Z.Pitvar u. 11., Hungary; email: z.klencsar@esr.hu LA - English DB - MTMT ER - TY - JOUR AU - Kovács, Eszter Mária AU - Baradács, Eszter AU - Kónya, Péter AU - Kovács-Pálffy, P AU - Harangi, Sándor AU - Kuzmann, Ernő AU - Kónya, József AU - M. Nagy, Noémi TI - Preparation and structure's analyses of lanthanide (Ln) -exchanged bentonites JF - COLLOIDS AND SURFACES A : PHYSICOCHEMICAL AND ENGINEERING ASPECTS J2 - COLLOID SURFACE A VL - 522 PY - 2017 SP - 287 EP - 294 PG - 8 SN - 0927-7757 DO - 10.1016/j.colsurfa.2017.02.085 UR - https://m2.mtmt.hu/api/publication/3208553 ID - 3208553 N1 - Funding Agency and Grant Number: EUEuropean Union (EU); European Regional DevelopmentEuropean Union (EU) [GINOP-2.3.2-15-2016-00008]; Hungarian National Research, Development, and Innovation Office [NKFIH K 120265] Funding text: This work was supported by the EU and co-financed by the European Regional Development [GINOP-2.3.2-15-2016-00008]; the Hungarian National Research, Development, and Innovation Office [NKFIH K 120265]. Imre Lajos Isotope Laboratory, Department of Colloid and Environmental Chemistry, University of Debrecen, 4032 Egyetem tér 1., Debrecen, Hungary Department of Solid State Physics, University of Debrecen, 4026 Bem tér 18/b, Debrecen, Hungary Geological and Geophysical Institute of HungaryH-1143, Hungary Department of Inorganic and Analytical Chemistry, Agilent Atomic Spectroscopy Partner Laboratory, University of Debrecen, Debrecen, H-4032, Hungary Institute of Chemistry, Eötvös Loránd University, 1117, Budapest, Hungary Cited By :8 Export Date: 5 February 2021 CODEN: CPEAE Correspondence Address: Nagy, N.M.; Imre Lajos Isotope Laboratory, 4032 Egyetem tér 1., Hungary; email: nagy.noemi@science.unideb.hu AB - The interaction between Lanthanides (Ln)- ions and Ca-bentonite and the structural changes accompanying were studied. Ln-exchanged bentonites were prepared from Ca-bentonite (Istenmezeje, Hungary) by ion exchange in three consecutive washings with lanthanide solutions. Scanning Eletronmicroscopy Energy Dispersive X-ray spectroscopy (SEM-EDX) studies showed even distribution of Lns and other components of bentonite. The natural bentonite and the lanthnide exchanged bentonites were characterized by X-ray diffraction (XRD), which revealed the same mineral composition, and the increase of the basal spacing of montmorillonite from 1.465 (Ca2+) to 1.577 nm (REE3+). The d001 basal spacing of lanthanide montmorillonite increases as the ion radius of the lanthanide cation increases. The Fe3+, and Lns3+ amount on the bentonite were determined by X-ray-fluorescence spectrometry (XRF) elemental analysis. The amount of exchanged Lns were determined by washing the Ln-bentonite with 1 M ammonium-acetate, and measuring the amount of Ln released, using inductively coupled plasma optical emission spectrometry (ICP-OES). In most Ln-bentonites, the quantity of the exchanged Ln ions was about 80–90% of the cation exchange capacity (CEC) of the bentonite. In case of some lanthanides bentonite (La3+, Ce3+, and Gd3+), however, the sorbed quantity of lanthanum ions was higher than the cation exchange capacity. In case of lanthanum-bentonite, the lanthanide quantity is as high as 136% of CEC. Moreover, the iron(III) content of lanthanum bentonite is less than that of the original Ca-bentonite. Mössbauer spectra of the La-, Ce-, and Gd-exchanged samples at 78 K revealed an unexpected magnetically split component that was absent from the Ca-bentonite. This component may belong to interlayer Fe. This iron can be released from the octahedral positions crystal lattice. © 2017 Elsevier B.V. LA - English DB - MTMT ER - TY - JOUR AU - Kuzmann, Ernő AU - Garg, VK AU - Singh, H AU - de Oliveira, AC AU - Pati, SS AU - Homonnay, Zoltán AU - Rudolf, M AU - Molnár, ÁM AU - Kovács, Eszter Mária AU - Baranyai, Edina AU - Kubuki, S AU - M. Nagy, Noémi AU - Kónya, József TI - Mössbauer study of pH dependence of iron-intercalation in montmorillonite JF - HYPERFINE INTERACTIONS J2 - HYPERFINE INTERACT VL - 237 PY - 2016 IS - 1 PG - 6 SN - 0304-3843 DO - 10.1007/s10751-016-1314-5 UR - https://m2.mtmt.hu/api/publication/3097530 ID - 3097530 N1 - WoS:hiba:000379534100001 2020-12-06 01:42 cikkazonosító nem egyezik Institute of Chemistry, Eötvös Loránd University, Budapest, Hungary Institute of Physics, University of Brasília, Brasília, DF, Brazil Imre Lajos Isotope Laboratory, Department of Colloid and Environmental Chemistry, University of Debrecen, Debrecen, Hungary Department of Inorganic and Analytical Chemistry, University of Debrecen, Debrecen, Hungary Department of Chemistry, Tokyo Metropolitan University, Tokyo, 192-0397, Japan Cited By :4 Export Date: 5 February 2021 CODEN: HYIND Correspondence Address: Kuzmann, E.; Institute of Physics, Brazil; email: kuzmann@caesar.elte.hu AB - 57Fe Mössbauer spectroscopy and XRD have successfully been applied to show the incorporation of Fe ion into the interlayer space of montmorillonite via treatment with FeCl 3 in acetone. The 78K 57Fe Mössbauer spectra of montmorillonite samples reflected magnetically split spectrum part indicating the intercalation of iron into the interlayer of montmorillonite via the treatment with FeCl 3+acetone and washed with water until the initial pH=2.3 increased to pH=4.14. It was found that the occurrence of intercalated iron in the form of oxide-oxihydroxide in montmorillonite increases with the pH. Intercalation was confirmed by the gradual increase in the basal spacing d001 with pH. © 2016, Springer International Publishing Switzerland. LA - English DB - MTMT ER - TY - JOUR AU - Kuzmann, Ernő AU - Singh, LH AU - Garg, VK AU - de Oliveira, AC AU - Kovács, Eszter Mária AU - Molnár, ÁM AU - Homonnay, Zoltán AU - Kónya, Péter AU - M. Nagy, Noémi AU - Kónya, József TI - Mössbauer study of the effect of rare earth substitution into montmorillonite JF - HYPERFINE INTERACTIONS J2 - HYPERFINE INTERACT VL - 237 PY - 2016 IS - 1 PG - 8 SN - 0304-3843 DO - 10.1007/s10751-016-1225-5 UR - https://m2.mtmt.hu/api/publication/3030404 ID - 3030404 N1 - N1 Funding Details: A127/2013, CAPES, Coordenação de Aperfeiçoamento de Pessoal de Nível Superior Institute of Physics, University of Brasília, Brasília DF, 70919-970, Brazil Institute of Chemistry, Eötvös Loránd University, Budapest, 1117, Hungary Isotope Laboratory, Department of Colloid and Environmental Chemistry, University of Debrecen, Debrecen, Hungary Geological and Geophysical Institute of Hungary, Hungary, 1143, Hungary Cited By :8 Export Date: 5 February 2021 CODEN: HYIND Correspondence Address: Kuzmann, E.; Institute of Chemistry, Hungary; email: kuzmann@caesar.elte.hu Funding details: Coordenação de Aperfeiçoamento de Pessoal de Nível Superior, CAPES, A127/2013 Funding details: Hungarian Scientific Research Fund, OTKA, K115913, K115784 Funding text 1: The financial supports from the CAPES (No A127/2013) and OTKA (No K115913 and K115784) grants are acknowledged. E.K. thanks to Dr. P. Kovacs-Palffy for the valuable discussion. AB - Novel montmorillonites were prepared by the exchange of the interlayer cations with a series of rare earth cations (La, Ce, Pr, Nd, Sm, Eu, Gd, Dy, Ho, and Er) and characterized by XRD, XRF, SEM, chemical analysis and 57Fe Mössbauer spectroscopy. An unexpected magnetically split component, assigned to iron being in the interlayer space, was observed in the Mössbauer spectra at 78K in some rare earth cation exchanged montmorillonite. This paper is the initial report about this observation. The transition of iron from the octahedral site to the interlayer and possible incorporation of rare earths in sites different from those which are in the interlayer space was concluded. © 2016, Springer International Publishing Switzerland. LA - English DB - MTMT ER - TY - JOUR AU - Komlosi, A AU - Kuzmann, Ernő AU - M. Nagy, Noémi AU - Homonnay, Zoltán AU - Kubuki, S AU - Kónya, József TI - Incorporation of Fe in the interlayer of Na-bentonite via treatment with FeCl3 in acetone JF - CLAYS AND CLAY MINERALS J2 - CLAY CLAY MINER VL - 55 PY - 2007 IS - 1 SP - 89 EP - 95 PG - 7 SN - 0009-8604 DO - 10.1346/CCMN.2007.0550107 UR - https://m2.mtmt.hu/api/publication/1354713 ID - 1354713 N1 - Megjegyzés-20477956 DOI: 10.1346/CCMN.2007.0550107 AB - The effect of FeCl3 in acetonic medium on the structure of Na-bentonite was studied using X-ray diffraction (XRD), Fe-57 Mossbauer spectroscopy, X-ray fluorescence spectroscopy and infrared spectroscopy to describe the structure of the bentonite before and after treatment. In the samples treated with FeCl3, an increase in the basal spacing was found by XRD, while a new magnetically split component assigned to Fe3+ incorporated within the interlayer regions of montmorillonite showed up in the low-temperature Mossbauer spectra. The Mossbauer parameters observed were close to those of Fe oxyhydroxides, suggesting the presence of some kind of nanoparticles. These results show that the treatment with acetonic FeCl3 solution is an effective method for introducing Fe into montmorillonite in the form of Fe3+ accommodated in the interlayer region. The treated samples proved to be efficient Lewis catalysts in the acylation of aldehydes (benzaldehyde and 4-OH-benzaldehyde) by acetic acid anhydride. LA - English DB - MTMT ER - TY - JOUR AU - Klencsár, Zoltán AU - Kuzmann, Ernő AU - Vértes, Attila TI - User-Friendly Software for Mössbauer-Spectrum Analysis JF - JOURNAL OF RADIOANALYTICAL AND NUCLEAR CHEMISTRY J2 - J RADIOANAL NUCL CHEM VL - 210 PY - 1996 IS - 1 SP - 105 EP - 118 PG - 14 SN - 0236-5731 DO - 10.1007/BF02055410 UR - https://m2.mtmt.hu/api/publication/117882 ID - 117882 LA - English DB - MTMT ER -