Effect of particle size analysis on the physicochemical characterization of Malaysian monazite

Abstract

Rare earth elements (REEs) are the elements that have become extremely important to our world of technology owing to their unique physical and chemical properties, and widely used in advanced technology. Monazite is one of the mineral phosphate that contain a high amount of REEs including thorium and a small amount of uranium. In Malaysia, monazite is exist as by-product (‘amang’) from tin mining originated from Ipoh, Perak. The objective of this study is to determine the effects of the different particles size of raw and ground (milled) monazite on the physicochemical properties. The effectiveness of extraction and separation process of monazite was affected by the size of the particle. Based on the particle size distribution analysis, all the monazite samples were found to be present in the size range of 11-190 μm. The morphological and elemental composition of the monazite mineral have been characterized by field emission scanning electron microscope (FESEM) integrated with energy dispersive X-ray spectrometer (EDX). The FESEM micrographs of the monazite showed an irregular spherical structures with different sizes. The chemical composition and the mineral phases present in monazite were studied by wavelength-dispersive X-ray fluorescence spectrometer (WD-XRF) and X-ray diffraction (XRD). The XRF analysis confirmed the presence of the major REEs such as Ce, La and Nd elements in the mineral. XRD analysis also identified (Ce, La, Nd and Th)PO4 as the major phases along with quartz as minor phase. According to the FESEM-EDX and XRF analysis, smaller particle size of monazite gave higher content of REEs compare to raw monazite.