Malaysian Journal of Analytical Sciences Vol 20 No 1 (2016): 44 - 50

 

 

 

PRODUCTION OF RARE EARTH ELEMENTS FROM MALAYSIAN MONAZITE BY SELECTIVE PRECIPITATION

 

(Penghasilan Unsur Nadir Bumi daripada Mineral Monazit Menggunakan Pemendakan Terpilih)

 

Che Nor Aniza Che Zainul Bahri*, Wadeeah M. Al- Areqi, Amran Ab. Majid, Mohd Izzat Fahmi Mohd Ruf

 

Nuclear Science Program, School of Applied Physics,

Faculty of Science and Technology,

Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor, Malaysia

 

*Corresponding author: anizazainul@gmail.com

 

 

Received: 2 November 2015; Accepted: 31 December 2015

 

 

Abstract

Rare earth elements (REEs) are very valuable and have high demands for advanced technology nowadays. REEs can be classified to light rare earth elements (LREEs) and heavy rare earth elements (HREEs). Malaysian rare earth ore especially monazite, is rich with LREEs compared to HREEs. Therefore a study was carried out to extract the REE from Malaysian monazite. The objectives of this study are to determine the content of REEs in Malaysian monazite leach solution, as well as to produce high grade of REEs. Concentrated sulphuric acid was used in digestion process and the filtrate containing the REEs was determined using Inductively Coupled Plasma- Mass Spectrometry (ICP-MS). Ammonia solution was used for REEs precipitation from monazite leach solution. The result indicated that REEs was successfully separated from monazite leach solution through selective precipitation using ammonia at pH 2.34 and the percentage of REEs that successfully separated was 70.03 – 81.85%. The percentage of REEs which successfully separated from final solution was 96.05 – 99.10%. Therefore, to have high purification of individual REEs, solvent extraction process should be carried out.

 

Keywords: monazite, rare earth elements (REEs), separation, selective precipitation

 

Abstrak

Unsur nadir bumi sangat berharga dan mempunyai permintaan yang tinggi dalam teknologi termaju masa kini. Unsur nadir bumi dapat dikelaskan kepada unsur nadir bumi ringan (LREEs) dan unsur nadir bumi berat (HREEs). Bijih nadir bumi Malaysia terutamanya monazit kaya dengan unsur nadir bumi ringan berbanding unsur nadir bumi berat. Dengan itu, satu kajian telah dilakukan untuk mengekstrak unsur nadir bumi dari monazit Malaysia. Objektif kajian ini adalah untuk menentukan kandungan unsur nadir bumi dalam larutan larut lesap monazit Malaysia serta menghasilkan unsur nadir bumi bergred tinggi. Asid sulfurik pekat telah digunakan untuk menghadamkan monazit dan hasil turasan yang mengandungi unsur nadir bumi ditentukan menggunakan ICP-MS. Larutan ammonia telah digunakan untuk memendakan torium daripada unsur nadir bumi dari larutan larut lesap monazit. Keputusan kajian mendapati unsur nadir bumi berjaya diasingkan dari larutan larut lesap monazit melalui mendakan terpilih menggunakan ammonia pada pH 2.34 dan peratus unsur nadir bumi yang berjaya diasingkan adalah antara 70.03 – 81.85%. Peratus unsur nadir bumi yang berjaya diasingkan daripada larutan akhir pula adalah 96.05 – 99.10%. Oleh itu, bagi menghasilkan unsur nadir bumi yang berketulenan tinggi maka proses pengekstrakan pelarut perlu dilakukan.

 

Kata kunci: monazit, unsur nadir bumi, pengasingan, pemendakan terpilih

 

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