Selection of a pre-treatment method to extract and separate rare earth elements and thorium from Indonesian monazite

Abstract

As an effort to reduce global carbon emissions, nations worldwide are now pursuing to maximize the application of clean technology. Rare earth elements (REE) and thorium are some materials utilized in eco-friendly technology. REE are used in many clean technology applications, including wind turbines and electric vehicles. At the same time, thorium can be used as fuel in a nuclear-based power plant to produce sustainable electricity. Indonesia has a potential economic monazite resource in the Bangka-Belitung Islands, which resource not only contains REE but also thorium. However, Indonesia currently has no commercial processing activity to produce rare earth or thorium products. Thus, a suitable monazite processing technology needs to be developed to process Indonesian monazite that contains both REE and thorium so Indonesia can be ready to fulfill the market demand for REE and thorium in the future. Due to the phosphate refractory nature of the monazite, however, the monazite ore requires a pre-treatment process to be amenable to leaching. This paper discusses the presently available monazite processing technologies, specifically the pre-treatment methods, from the literature and discusses the most suitable method to process Indonesian monazite. A preliminary experiment was also performed to test the applicability of the selected method.