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Radiochim. Acta 99, 349–357 (2011) / DOI 10.1524/ract.2011.1838 © by Oldenbourg Wissenschaftsverlag, München Neptunium(V) sorption on kaolinite By S. Amayri∗, A. Jermolajev and T. Reich Institue of Nuclear Chemistry, Johannes Gutenberg-Universität, 55099 Mainz, Germany (Received May 15, 2010; accepted in final form February 16, 2011) Sorption / Neptunium / Kaolinite / Clay Summary. The sorption behavior of neptunium(V) onto the clay mineral kaolinite was studied in batch experiments under different experimental condi- tions: [Np(V)] = 7×10−12–8×10−6 M, solid

American Mineralogist, Volume 95, pages 651–654, 2010 0003-004X/10/0004–651$05.00/DOI: 10.2138/am.2010.3408 651 Letter Pressure-induced transformations in kaolinite Mark D.WeLch1,* anD WiLson a. crichton2,3 1The Natural History Museum, Cromwell Road, London SW7 5BD, U.K. 2The European Synchrotron Radiation Facility, Rue Jules Horowitz, 38043 Grenoble, Cedex 9, France 3Department of Earth Sciences, University College London, Gower Street, London WC1E 6BT, U.K. abstract The compressional behavior of kaolinite (space group C1) from Keokuk, Iowa, has been

American Mineralogist, Volume 99, pages 681–695, 2014 0003-004X/14/0004–681$05.00/DOI: 681 * E-mail: Kaolinite transformation into dickite during burial diagenesis Javier Cuadros1,*, raquel vega1, aleJandro TosCano1 and Xabier arroyo2 1Department of Earth Sciences, Natural History Museum, Cromwell Road, London SW7 5BD, U.K. 2Faculty of Geological Sciences, Complutense University of Madrid, C/ José Antonio Novais no. 2, Ciudad Universitaria, 28040 Madrid, Spain absTraCT The mechanism of kaolinite

Kinetic behavior of partially dehydroxylated kaolinite Victor A. Drits1,* AnD ArkADiusz Derkowski2 1Geological Institute of the Russian Academy of Science, Pyzhevsky per. 7, 119017 Moscow, Russia 2Institute of Geological Sciences, Polish Academy of Sciences, Senacka 1, 31-002 Krakow, Poland AbstrAct The multi-cycle heating and cooling thermogravimetric (TG) method was used to study the kinetic behavior of three kaolinite samples: defect-free Keokuk kaolinite, KGa-2 with a very low degree of structural order, and KGa-1 having intermediate structural order. In

are natural materials, inexpensive, commonly available, non-toxic, and environmentally harmless. Clays include clay minerals, especially phyllosilicates with layered structures. Phyllosilicates can be used as sorbents of heavy metals cations, for fixing metal or metal oxide NPs ( Weiss & Kužvart, 2005 ). Kaolinite/TiO 2 composite is an example of an extremely useful material that improves the photocatalytic degradation of organic contaminants in water and air, particularly subsequent to calcination. The photoactivity of the kaolinite/TiO 2 composite increased

Cuadros and Dudek (2006). In the light of these studies, smectite kaolinization is a solid-state transformation that proceeds through progressive removal of tetrahedra from smectite layers and the corresponding increase of OH groups in the octahedral sheet. This process leads to the development of kaolinite-like patches or domains within smectite layers. However, the development of the patches and their collapse to ~7 Å (as measured by XRD) do not progress si- multaneously, because the collapse happens only when the patches acquire sufÞ cient size. In a similar

Zeitschrift für Kristallographie, Bd. 119, S. 161—175 (1963) Structure defects in kaolinite By G. B. Mitra Department of Physics, Indian Institute of Technology, Kharagpur, India With 4 figures (Received November 13, 1962; in revised form March 8, 1963) Auszug Zur Bestimmung der Art und des Umfangs der Unordnung des Kaolinits wurde eine Probe dieses Minerals von Singhbhum in Indien röntgenographisoh und elektronenmikroskopisch untersucht. Aus der Verbreiterung der Inter- ferenzlinien und aus Fourier-Analysen ergab sich, daß die Teilchen blättchen- förmig sind bei

fluid/rock ratio ( Rozalén et al. 2008 ). In comparison to the two above-mentioned transformation pathways, the transformation of 1:1 type clay minerals to 2:1 type ones is less commonly observed. The illitization of kaolinite is mostly reported for the transformation of 1:1 to 2:1 type ones, mainly occurring in diagenesis and low-grade metamorphism ( Dunoyer de Segonzac 1970 ; Sommer 1978 ; Dutta and Suttner 1986 ; Lanson et al. 1996 , 2002 ), and under hydrothermal conditions ( Šucha et al. 1998 ; Bentabol et al. 2003a , 2003b , 2006 ). Such transformation

Radiochim. Acta 95, 569–575 (2007) / DOI 10.1524/ract.2007.95.10.569 © by Oldenbourg Wissenschaftsverlag, München Sorption of tetravalent plutonium and humic substances onto kaolinite By N. L. Banik, R. A. Buda, S. Bürger#, J. V. Kratz∗ and N. Trautmann Institut für Kernchemie, Johannes Gutenberg-Universität, 55099 Mainz, Germany (Received July 24, 2006; accepted in revised form May 9, 2007) Plutonium / Oxidation state / Kaolinite / Sorption / Desorption / Humic acid / Fulvic acid Summary. The sorption of tetravalent plutonium onto kaoli- nite, a clay mineral

detailed studies on kaolinite and illite clays in relation to geotechnical properties;whether or not both clays have an important role in engineering design. The reduction in strength of soft clays causes a decrease in bearing capacity and excessive settlement [ 7 ]. Kaolinite does not respond to chemical modifications but Na-smectite is highly sensitive to the variation of the chemistry of the pore fluid [ 8 ]. Lime-clay reactions depend on several factors such as mineralogical composition of clayey soil, the quantity of lime employed for treatment, and moisture content