Article Sidebar

PDF
Published: 2023-11-24
Abstract Views: 132
Views PDF: 65
DOI: https://doi.org/10.53747/nst.v12i2.351
Issue
Vol. 12 No. 2 (2022)
Section
Articles
How to Cite
Hoang Xuan, T., Nguyen Thi, M., Hoang Thi, T., Ngo Van, T., & Hoang, N. (2023). Investigation of Vietnamese monazite concentrate decomposition by alkaline (KOH) baking method. Nuclear Science and Technology, 12(2), 28-35. https://doi.org/10.53747/nst.v12i2.351

Investigation of Vietnamese monazite concentrate decomposition by alkaline (KOH) baking method

Thi Hoang Xuan1, Men Nguyen Thi, Tuyen Hoang Thi, Tuyen Ngo Van, Nhuan Hoang
1 s:65:"Institute of Technology for Radioactive and Rare Elements (ITRRE)";

Main Article Content

Abstract

The alkaline (NaOH) hydrometallurgy for monazite concentrate is currently being used in the industrial production of total rare earth oxides (TREOs) and thorium oxide (ThO2). Besides the acknowledged advantages, the hydrometallurgical process also has certain disadvantages such as the requirement for ultra-fine grinding to -325 mesh, and the hydrometallurgy time extended from 8 to 10 hours to achieve ~93 % efficiency. The present paper report a new roasting process using potassium hydroxide (KOH) applied to Vietnamese monazite concentrates. The experimental data were collected using mass analysis, XRD, and ICP-OES analysis. The optimal efficiency of the process is ~95% after roasting time of 0,5 hours, the temperature at 250oC, and KOH:monazite mass ratio = 1:1. Thereby, the alkaline (KOH) roasting process has solved the limitations of the alkaline (NaOH) hydrometallurgy and shows the development potential in deep processing of the monazite concentrate in Vietnam.

Article Details

Keywords

Vietnamese monazite concentrate, alkalaline (KOH) baking process.

References

[1]. C. Gupta and N. J. B. R. Krishnamurthy, Florida, "Extractive metallurgy of rare earths CRC press," vol. 65, pp. 70-75, 2005.
[2]. P. Melard, "Quality Control on an Industrial Scale at the La Rochelle Rare Earths Plant," in The Rare Earths in Modern Science and Technology: Springer, 1980, pp. 517-526.
[3]. M. Y. Sulaiman, "An Overview of the Rare-Earth Mineral Processing Industry in Malaysia," Materials Science Forum, vol. 70-72, pp. 389-396, 1991.
[4]. R. C. De and P. Maurice, "Treatment of monazite," ed: Google Patents, 1957.
[5]. C. Ney, L. Tauhata, and D. Oliveira Filho, "Dose equivalent estimate of works in a Brazilian monazite sand plant," in 8. International congress of the International Radiation Protection Association (IRPA8), 1992.
[6]. D. da Costa Lauria and E. R. J. R. p. d. Rochedo, "The legacy of monazite processing in Brazil," vol. 114, no. 4, pp. 546-550, 2005.
[7]. A. Kumari et al., "Advanced process to dephosphorize monazite for effective leaching of rare earth metals (REMs)," vol. 187, pp. 203-211, 2019.
[8]. Y. Ni, J. M. Hughes, and A. N. J. A. M. Mariano, "Crystal chemistry of the monazite and xenotime structures," vol. 80, no. 1-2, pp. 21-26, 1995.
[9]. R. M. Hazen and L. W. J. A. M. Finger, "Crystal structure and compressibility of zircon at high pressure," vol. 64, no. 1-2, pp. 196-201, 1979.
[10]. L. B. Thuan (2015). Deep procesing activities of rare earth ores in the Institute for Technology of Radioactive and Rare Elements (ITRRE): a journey of 25 years. Available: http://www.itrre.gov.vn/detail-news-view-1-10-72_che-bien-sau-quang-dat-hiem-tai-vien-xa-hiem.html
[11]. P. Q. Trung, "The final report of Ministry-level Science and Technology Project (2003-2004): Research on technology to processing the major rare earth minerals in Vietnam by upgraded Indian monazite pilot (BO/03/03-07)," 3/2005.