(744e) Distributions and Associations of Rare Earth Elements in Fly Ash Using Laser Ablation High Resolution Mass Spectrometry

Laser ablation high resolution mass spectrometry (LA-HR-MS) was used to study the distributions and associations of rare earth elements with other major and minor elements in coal fly ash samples using line scans and statistical analysis. Associations of the REEs with major elements, which compose different components of a fly ash, were analyzed. The results indicate that there are good positive correlations amongst the light rare elements (LREE) and thorium, which is a possible indication of monazite, and a good correlation between the heavy rare earth elements (HREE) and yttrium, which is an indication of xenotime. Associations of the rare earths with elements in the glass fraction and volatile elements usually found on the surface of fly ash particles will be discussed. Dissimilar correlations of elements with the LREE and HREE may indicate differences in the thermal stabilities of source REE minerals, and may also help determine the location and best extraction method for recovery of LREEs and HREEs in coal and coal ash.