%0 Journal Article
%T Aplicaciones de los minerales arcillosos de Cayo Guan, Cuba, como adsorbentes de metales pesados y materia prima cer芍mica
%A Fonseca
%A D.
%A Barba
%A F.
%A Calejas
%A P.
%A Recio
%A P.
%J Bolet赤n de la Sociedad Espaˋola de Cer芍mica y Vidrio
%D 2012
%I Sociedad Espa?ola de Cer芍mica y Vidrio
%R 10.3989/cyv.372012
%X It has been studied by Analysis Heating Microscope 每 Optical the behaviour of some kaolinitic clays from a reservoir of Cayo Guan rich in iron oxides and low silica content proving to be a refractory materials whose softening appears after 1500 ∼C. It has obtained the workability diagram of the different clay minerals calculating the plasticity by the method of Casagrande spoon; only one of the samples is in the area suitable for extrusion. Vitrification diagrams report that the capacity of water absorption is < 0.6 % when the temperature of 1400 oC is achieved. We have designed a program to calculate compositions of porcelain stoneware prepared from these modified clays adding low-cost raw materials that facilitate the formation of glassy phase ((potassium feldspar and glass cullet) and/or increase the silica (sand and diatomaceous earth used as filters in the brewing industry). With one of these compositions, prepared in the laboratory (60 % of clay, 30 % feldspar and 10 % of diatomaceous earth), calcined at 1250 oC with a heating rate of 15 ∼C/min, the results were: water absorption 0.8 %, and linear shrinkage 21 % without any deformation observed. These clays have been treated with acid to eliminate its high iron content and study its application as an sorbent of heavy metals as Cd2+, Cr3+. The results of the immobilization of these elements have been compared with those obtained with thermally activated vermiculite at 800 ∼C, showing that the treated samples show sorption of both cadmium and chromium below the vermiculite, but the non-treated ones are suitable to remove chromium; this is because these clays do not contain in its composition exchangeable ions (Ca2+, Mg2+, Na+, K+), and even if they are chemically activated only the presence of Fe ions is which produces form bindings (Crx.Fe1-x) (OH)3 which favor Cr sorption. En Cayo Guan, municipio de Moa, hay junto a las importantes explotaciones industriales de lateritas, minerales arcillosos cuya caractarizaci車n qu赤mica, mineral車gica y evoluci車n de fases con la temperatura han sido objeto de estudio por estos autores en un anterior trabajo; entre las caracter赤sticas f赤sicas, qu赤micas y mineral車gicas del yacimiento destacan los altos contenidos de 車xidos de hierro y aluminio, bajas concentraciones de SiO2 y 車xidos alcalinos, y la caolinita como mineral m芍s abundante, adem芍s de hematita, gibsita y goethita en forma de geles. Se pretende en esta investigaci車n estudiar sus propiedades tecnol車gicas para dilucidar la posible aplicabilidad a estos recursos minerales en la fabricaci車n de ladrillos, baldos
%K clay minerals
%K heavy metals adsorptions
%K porcelain stoneware
%K ceramic raw material
%K minerales arcillosos
%K adsorci車n de metales pesados
%K gres porcel芍nico
%K materia prima cer芍mica
%U http://ceramicayvidrio.revistas.csic.es/index.php/ceramicayvidrio/article/view/1158/1191