Sains Malaysiana 47(8)(2018): 1873–1882

http://dx.doi.org/10.17576/jsm-2018-4708-28

 

Pengekstrakan dan Penulenan Torium Oksida (ThO2) daripada Mineral Monazit

(Extraction and Purification of Thorium Oxide (ThO2) from Monazite Mineral)

 

CHE NOR ANIZA CHE ZAINUL BAHRI, AZNAN FAZLI ISMAIL*, AMRAN AB. MAJID,

MOHD IZZAT FAHMI MOHD RUF & WADEE'AH MUTAHIR AL-AREQI

 

Nuclear Science Programme, School of Applied Physics, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor Darul Ehsan, Malaysia

 

Received: 2 March 2018/Accepted: 27 April 2018

 

ABSTRAK

Monazit merupakan mineral fosfat yang mengandungi unsur nadir bumi, torium dan uranium dalam kepekatan tertentu. Kepekatan torium dalam monazit di Malaysia dilaporkan sekitar 2,525.0 - 40,868 ppm dan berpotensi digunakan sebagai bahan api untuk kegunaan reaktor nuklear torium. Sehubungan dengan itu, kajian ini bertujuan mengkaji proses pengekstrakan dan penulenan torium oksida (ThO2) daripada monazit tempatan. Proses pengekstrakan dan penulenan ThO2 dibahagikan kepada empat peringkat iaitu proses penghadaman, pengasingan, pengekstrakan pelarut dan pengkalsinan. Pencirian sampel telah dilakukan melalui analisis spektrometri jisim gandingan plasma teraruh (ICP-MS), analisis termogravimetri (TGA), pembelauan sinar-X (XRD) dan mikroskopi pengimbas elektron dengan spektroskopi serakan tenaga sinar-X (SEM-EDS). Proses penghadaman telah menghasilkan larutan larut lesap monazit ((Th,REE,U)(SO4)2) yang mengandungi sehingga 99.77 ± 7.84 mg torium. Unsur nadir bumi (La, Ce, Nd, Pr, Sm, Eu dan Gd) telah diasingkan daripada torium pada peratusan 96.73%. Manakala larutan Th(NO3)4 dan ThO2 yang dihasilkan masing- masing berketulenan 97.10 ± 0.74% dan 98.85 ± 0.69%. Sehubungan dengan itu, kajian ini menunjukkan bahawa pengekstrakan dan penulenan ThO2 daripada monazit tempatan boleh dilakukan melalui proses pengekstrakan berperingkat.

 

Kata kunci: Monazit; pengekstrakan; penulenan; torium oksida

 

ABSTRACT

Monazite is a phosphate mineral containing rare earth elements (REEs), thorium and uranium at certain concentrations. The thorium concentration in Malaysian monazite was reported in the range of 2,525.0 - 40,868 ppm and potentially be used as fuel in thorium nuclear power reactor. Therefore, this study aimed to investigate the extraction and purification process of thorium oxide (ThO2) from local monazite. The extraction and purification process of ThO2 divided into four stages which are digestion, separation, solvent extraction and calcination. Sample characterizations were carried out via inductive coupled plasma-mass spectrometry (ICP-MS), thermogravimetric analysis (TGA), x-ray diffraction (XRD) and scanning electron microscope-energy dispersive x-ray spectroscopy (SEM-EDS). The digestion process produced monazite leach solution ((Th,REE,U)(SO4)2) containing up to 99.77 ± 7.84 mg of thorium. Rare earth elements (La, Ce, Nd, Pr, Sm, Eu and Gd) were separated from thorium at a percentage of 96.73%. Meanwhile, the produced Th(NO3)4 and ThO2 has the purity of 97.10 ± 0.74% and 98.85 ± 0.69%, respectively. Therefore, this study showed that the extraction and purification of ThO2 from local monazite are possible to achieve through the staggered extraction process.

 

Keywords: Extraction; monazite; purification; thorium oxide

 

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*Corresponding author; email: aznan@ukm.edu.my

 

 

 

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