Characterization and potential applications of different powder volcanic ash

Abstract

Objectives: In this study, the crystalline phase, microstructure, chemical composition, and morphology of the powder of volcanic ashes from three different places have been investigated. Methods: The raw materials were initially milled and the particle size was decreased to approximately 74 µm. X-ray diffraction (XRD), chemical analysis (XRF and ICP-OES technique), Fourier transform infrared spectroscopy and scanning electron microscopy were used to examine the obtained samples. Results: It was found that the volcanic ashes exhibit clear variations in mineralogy, chemical compositions, stretching vibrational modes, and morphological structure. All the samples have an amorphous phase and contain SiO2, Al2O3, CaO, and Fe2O3 as their major constituents. Other oxides such as K2O, MgO, MnO, Na2O, P2O5, TiO2, and SO3 were found in minor percentages. The morphology of the samples showed a variety of volcanic mixtures with irregular shapes. Conclusions: The abundant volcanic ash can be used as a new low-cost natural material in several applications such as in construction materials, ceramic industry, water purification, geopolymers, and other advanced technologies.