Ponente
Descripción
Dayaris Hernández1, Frank González-Sanz2, Juan Jiménez3, Aramis Rivera1*
1Zeolites Engineering Laboratory, Institute of Materials Science and Technology (IMRE), University of Havana, Havana, Cuba
2 Chemistry Faculty, University of Havana, Havana, Cuba
3 University Laboratory of Characterization of the Structure of the Substance, (LUCES), Institute of Materials Science and Technology (IMRE), University of Havana, Cuba
* Corresponding author: aramis@imre.uh.cu
The industrial use of clays is based on their exceptional physical-chemical properties. The detailed study of their structure and behavior through different characterization techniques is essential to achieve a full understanding of their properties, and a more efficient use. Their abundance in Cuba, and friendly environmental character, promote their academic and economical interest. The exploitation of natural clays deposits such as bentonite (Managua, Havana) and palygoskite (Pontezuela, Camagüey), first involves the application of purification procedures in order to remove contaminants and spurious phases, and then the performance of a thorough physical-chemical analysis.
The aim of this work is to clarify the mineralogical formula of the main phases in samples of bentonite (Bent) and palygorskite (Pal). In order to purify both samples, they were submitted to a hydrothermal procedure to remove the iron (Fe3+), followed by grinding and sieving. Bent and Pal samples, before and after being chemically treated with hydrochloric acid (HCl 0.1 M) and sodium chloride (NaCl 1 M) solutions, were characterized by X-ray fluorescence and X-ray diffraction. The results indicated an important decrease in the calcium amount, as well as a significant increment in the sodium percent, suggesting the obtaining of a sodic sample without calcite as spurious phase. The main mineralogical phases present in the samples were montmorillonite and palygorskite. Other mineral phases, as quartz and calcite were also identified.
