BCR leaching procedure to evaluate the mobilization behaviour of ion adsorption type REE deposit in I-type granite weathering profiles

Rare earth elements (REE) with specific application value have become the relatively important strategic resource for all countries. These so called ‘technology minerals’ are in increasing demand due to rapidly rising use in consumer technology, renewable energy generation systems, automotive industry, and other high technology sectors. In order to provide information on the chemical processes in mobilization behaviour of ion-adsorption type REE, this study investigated the extraction of REE from ion-adsorption clay deposit samples from weathering I-type granite profiles (saprolite horizon) at Maran, Pahang and Mersing, Johor (Eastern Belt of Peninsular Malaysia). Using a 0.5 M ammonium sulfate solution (adjusted at pH = 4), samples were leached in 1 hour through a Bureau of Certified Reference (BCR) leaching using BCR-701 standard, chosen based on experimental evidence to optimize the leachable REE. The Al2O3 concentration (27-31 wt.%) in saprolite horizon indicates depleted (change