Rare Earth Element: Future Precious Metals

Credit picture: Thermo Fisher Scientific

Rare earth element (REE) has broadly various modernized application such as green energy, magnet, medical tools, cell phone, fluorescent lighting, glass, ceramics, catalytic converter, lithium-ion battery, and much more. In periodic table, they located in lanthanides series : Lanthanum (La), Cerium (Ce), Praseodymium (Pr), Neodymium (Nd), Promethium (Pm), Samarium (Sm), Europium (Eu), Gadolinium (Gd), Terbium (Tb), Dysprosium (Dy), Holmium (Ho), Erbium (Er), Thulium (Tm), Ytterbium (Yb), Lutetium (Lu), plus Scandium (Sc) and Yttrium (Y). All rare earth elements are metallic form so that they often referred as rare earth metal. The similar properties make them found together in geological deposits, such as bastnasite, monazite, and xenotime. In general, they found in carbonate and phosphate mineral compound. Despite its name, rare earth metals, these metals are quite abundant in the Earth’s crust. Even so, because of its geological characteristic, rare earth metals are found in very scattered situation so that it need several stages to obtain each element which require high cost.

This metal group was first discovered in 1787 by a Swedish army named Karl Axel Arrhenius. He collected the black mineral Ytterbit from feldspar and quartz mining near the village of Ytterby, Sweden. This mineral was successfully separated by J. Gadoli in 1794 by obtaining the Ytterbit mineral. Subsequently, the mineral was renamed to Gadolinite in 1800. The discovery of this new element has led to other rare earth elements discovery such as in 1804 Klaporth et.al. discovered Cerium Oxide. Followed in 1828, Belzerius successfully obtained Thoria mineral from Thorite mineral. Mosander et.al. (1842) succeed to separate Yttria compound to become three elements through fractional sedimentation utilized oxalic acid and hydroxide. Those elements are Yttrium, Terbium, and Erbium. Based on Marc Delafontaine’s clue, Paul Emile Lecoq de Boisbaudran obtained Samarium from Samarskite mineral. The separation of Praseodymium and Neodymium that contained in Samarium was done by Welsbach and team in 1885. Gadolinium was extracted from Ytterbium mineral which previously obtained by J.C.G de Marginac in 1880. Finally, in 1907, de Boisbaudran succeed to separate Ytterbium into Neoytterbium and Lutetium. Besides, he obtained another element, namely Dysprosium. The Erbium, Holmium, and Thulium were separated from Erbium and Terbium by P.T. Cleve.

Up to date China dominates the world REE markets, nevertheless Indonesia has a big potential to develop REE market because Indonesia has monazite, xenotime, and ilmenite deposits especially in Bangka Belitung Island area which found as side product of tin mining. Furthermore, REE deposit also found in Borneo Island which identified as alluvium panning product to obtain gold and diamond but currently only available limited in West Borneo and Central Borneo. PTBGN – BATAN and PSTA – BATAN are two research institute in Indonesia that conduct research extraction of REE. PTBGN processes the up-stream project which means extracting the ore to become hydroxide compound of mixed REE whilst PSTA continuing the project by separating and purifying the hydroxide compound of mixed REE. Furthermore, PSTA that lead by Ir. Moch. Setyadji, MT. has written a document of metallurgical test work and conceptual design pilot plant REE processing. Based on forecasting data, REE sale value is higher than gold sale value. There are some things to prepare the project such as regulation that support REE purification process, adequate infrastructure, modal, etc. The government support will be helpful to accelerate the REE industrial development in Indonesia.