0438732 - ÚACH 2015 RIV NL eng J - Journal Article
Štengl, Václav - Popelková, Daniela - Matys Grygar, Tomáš
Composite pigments based on surface coated kaolin and metakaolin.
Applied Clay Science. Roč. 101, NOV (2014), s. 149-158. ISSN 0169-1317. E-ISSN 1872-9053
R&D Projects: GA MPO FR-TI1/006
Institutional support: RVO:61388980
Keywords : Kaolin * Homogeneous hydrolysis * Thioacetamide * Urea * Mullite * Metakaolin
Subject RIV: CA - Inorganic Chemistry
Impact factor: 2.467, year: 2014 ; AIS: 0.674, rok: 2014
DOI: https://doi.org/10.1016/j.clay.2014.07.030

Synthesis: The method of homogeneous hydrolysis of Fe, Co, Cr, Ni, Mn,Ti, Al, and Zn salts with urea in aqueous solutions in the presence of substrates (kaolin, metakaolin and mullite) was used for the preparation of composite pigments. In these composites individual kaolinite platelets were covered by a thin layer of hydroxide or oxy-hydroxides of selected metals, which were transformed into a metal oxide layer strongly bond to the aluminosilicate surface by heat treatment. An analogous method, homogeneous hydrolysis of thioacetamide in the presence of Cd and Zn salts was used for pigments based on sulphides. Characterization: The mineralogical composition of the pigments was identified by X-ray powder diffraction (XRD), the particle morphology was studied by transmission electron microscopy (TEM) and the color was characterized in CIEL*a*b colours coordinates. Results: The kaolin and metakaolin coated with layer of metal oxides are interesting new composite materials, obtained by a very simple preparation process at a low cost. (C) 2014 Elsevier B.V. All rights reserved.
Permanent Link: http://hdl.handle.net/11104/0242157