Estudio de las propiedades físicas de zeolita natural (aluminosilicato) de tipo clinoptilolita para remplazo parcial del cemento portland

Abstract

This study shows physical and chemical characteristics of natural zeolites (ZN) called ZA, ZZ, ZI from outcrops of the Chongón Colonche Mountain range located in the Guayas province of Ecuador and of the cement Type GU (CGU) for commercial use, with the purpose to determine if they can be supplemental cement material (SCM). Physical characteristics (density and fineness applying INEN and ASTM standards), morphological characteristics in the Scanning Electron Microscope (SEM) and elemental composition are determined by X-ray scattering spectroscopy (EDS). Prior to the tests, the samples that require grinding are prepared to obtain granules smaller than 75 microns. Densities of 3,071, 2,449, 2,511 and 2,494 grams per cubic centimeter and fineness percentages of 99.95, 99.04, 99.51, and 99.35 are obtained for CGU, ZA, ZZ and ZI, respectively. The experimental results, SEM micrographs and EDS spectra reveal that all samples have potential as SCM, highlighting ZA and ZZ with characteristics closer to CGU. All have a high pozzolanic capacity in the content of silica, alumina and iron oxide, exceeding the minimum specified by the ASTM C 618 standard. On the other hand, the siliconaluminum ratio between 2.67 and 4.83 shows the presence of clinoptilolites that have demonstrated efficacy as SCM. The compatibility in terms of its structure, sizes and chemical composition is obvious, however, for subsequent studies it should be taken into account that CGU cement is highly silicic compared to other cements used in studies with zeolites.