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

 

Diserahkan: 2 Mac 2018/Diterima: 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

 

RUJUKAN

 

Abrão, A., Freitas, A.A.D. & Carvalho, F.M.S.D. 2001. Preparation of highly pure thorum nitrate via thorium sulfate and thorium peroxide. Journal of Alloys and Compounds 323: 53-56.

Al- Areqi, M.W., Che Zainul Bahri, C.N.A., Majid, A.A. & Sarmani, S. 2016. Separation and radiological impact assessment of thorium in Malaysian monazite processing. Malaysia Journal of Analytical Sciences 20(4): 770-776.

Al-Areqi, M.W., Che Zainul Bahri, C.N.A., Majid, A.A. & Sarmani, S. 2017. Solvent extraction of thorium from rare earth elements. Malaysia Journal of Analytical Sciences 21(6): 1250-1256.

Al-areqi, W.M., Majid, A.A., Sarmani, S. & Che Zainul Bahri, C.N.A. 2015. Thorium: Issues and prospects in Malaysia thorium. AIP Conference Proceedings 1659: 040005 https:// doi.org/10.1063/1.4916865.

Ali, A.M.I., El-Nadi, Y.A., Daoud, J.A. & Aly, H.F. 2007. Recovery of thorium (IV) from leached monazite solutions using counter-current extraction. International Journal of Mineral Processing 81(4): 217-223.

Amaral, J.C.B.S. & Morais, C.A. 2010 Thorium and uranium extraction from rare earth elements in monazite sulphuric acid liquor through solvent extraction. Minerals Engineering 23: 498-503.

Amran, A.M., Muhamad, S.Y., Redzuwan, Y., Ismail, B. & Tan, K.C. 2007. Impak aktiviti pemprosesan amang ke atas sistem air tertutup dan persekitaran. The Malaysian Journal of Analytical Sciences 11(2): 388-394.

Akademi Sains Malaysia. 2011. Industri Nadir Bumi: Melonjakkan Ekonomi Hijau Malaysia ke Hadapan. Perpustakaan Negara Malaysia: Akademi Sains Malaysia & Majlis Profesor Negara.

Cardearelli, F. 2008. Materials Handbook. 2nd ed. New Jersey: Springer.

Cotton, S. 2006. Lanthanide and Actinide Chemistry. New York: John Wiley & Sons.

Gupta, C.K. & Krishnamurthy, N. 1992. Extractive Metallurgy of Vanadium. Amsterdam: Elsevier Science Publisher B.V.

Hubert, S., Barthelet, K., Fourest, B., Lagarde, G., Dacheux, N. & Baglan, N. 2001. Influence of the precursor and the calcination temperature on the dissolution of thorium dioxide. Journal of Nuclear Material 297(2): 206-213.

Hughes, K.C. & Singh, R. 1980. The isolation of thorium from monazite by solvent extraction. Hydrometallurgy 6(1-2): 25-33.

Hyde, E.K. 1959. The Radiochemistry of Thorium. Bekerly, California: U.S Atomic Energy Commission.

IAEA TECDOC. 2005. Thorium Fuel Cycle-Potential Benefits and Challenges. IAEATECDOC-1450, International Atomic Energy. Vienna, Austria.

Johnsson, K.O. & Winget, R.H. 1959. Pilot Plant Preparation of Thorium and Thorium-Uranium Oxides. Atomic Energy.

Morss, L.R., Edelstein, N., Fuger, J. & Katz, J.J. 2008. The Chemistry of Actinide and Transactinide Elements. 3rd ed. Netherlands: Springer.

Meor Yusoff, M.S. & Latifah, A. 2002. Rare earth processing in Malaysia: Case study of ARE and MAREC plants. Proceedings of Regional Symposium on Environment and Natural Resources 1: 287-295.

Meyer, G. & Morss, L.R. 1991. Synthesis of Lanthanide and Actinide Compounds. 2nd ed. The Netherlands: Kluwer Academic Publishers.

Mohd Ruf, M.I.F., Che Zainul Bahri, C.N.A., Al-Areqi, W.M. & Majid, A.A. 2016. Rare earth elements (REEs) in various Malaysian rare earth ores standardless EDXRF application for quantification of thorium (Th), uranium (U) and rare earth elements (REEs) in various Malaysian rare earth ores. The 2016 UKM FST Postgraduate Colloquium. Vol. 1784.

Nuri, H.L., Prayitno, P., Jami, A. & Pancoko, M. 2014. Kebutuhan desain awal pada pilot plant pengolahan monasit menjadi thorium oksida (ThO2). Beranda 35(2): 131-141.

Oktay, E. & Yayli, A. 2001. Physical properties of thorium oxalate powders and their influence on the thermal decomposition. Journal of Nuclear Materials 288(1): 76-82.

Padmanabhan, V.M., Saraiya, S.C. & Sundaram, A.K. 1960. Thermal decomposition of some oxalates. Journal of Inorganic and Nuclear Chemistry 12(3-4): 356-359.

Peelman, S., Sun, Z.H.I., Sietsma, J. & Yang, Y. 2016. Leaching of rare earth elements: Past and present. 1st European Rare Earth Resources Conference Milos04: 07/09/2014.

Rabie, K.A., Mahmoud, K.F. & Hussein, A.E.M. 2013. Monazite-uranium separation and purification applying oxalic-nitrate- TBP extraction. Arab Journal of Nuclear Sciences and Applications 46(1): 11-14.

Runianujam, A., Mukherjcc, A., Dhunuvad, R.K. & Division, F.R. 1989. Separation and purification of uranium product from thorium in thorex process by precipitation technique. International Nuclear Information System, Government of India Atomic Energy Commission. Bombay, India.

Ryabchikov, D.I & Gol’braikh, E.K. 1963. The analytical chemistry of thorium. International Series of Monographs on Analytical Chemistry. Oxford: Pergamon Press.

Sato, T. 1970. The extraction of thorium (IV) from sulphuric acid solutions by long-chain aliphatic amines. Journal of Inorganic and Nuclear Chemistry 32(4): 1341-1349.

Shaw, K.G. 1953. A process for separating thorium compounds from monazite sands. Iowa State University, Retrospective Theses and Dissertation (Unpublished).

White, G.D., Bray, L.A. & Hart, P.E. 1980. Optimization of thorium oxalate precipitation conditions relative to thorium oxide sinterability. Journal of Nuclear Materials 96(3): 305-313.

 

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

 

 

 

 

 

sebelumnya