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An Overview of Rare Earth Ores Beneficiation in Vietnam

Nhu Thi Kim Dung, Pham Van Luan, Vu Thi Chinh, Tran Van Duoc

Inżynieria Mineralna

2021

no. 2

227--236

Rare earth metals are used in electricity, electronics, nuclear, optics, space, metallurgy, superconducting and super magnetic materials, glass and ceramics, and agriculture. Some rare earth elements are added to fertilizers for crops and some trials for animal feed. Rare earth elements, except for radioactive promethium, are relatively abundant in the earth's crust. Vietnam has a tremendous rare earth potential, distributed mainly in the Northwest, including Nam Xe, Dong Pao, Muong Hum, and Yen Bai. There are many research projects on rare earth ores of different types globally, but the focus is mainly on the essential minerals, including monazite, xenotime, and bastnaesite. This report summarizes research data on rare earth ore intending to produce a general assessment of rare earth ore and its beneficiation technology in Vietnam.

The adsorption mechanism of Al(III) and Fe(III) ions on bastnaesite surfaces

Cao Shiming, Cao Yijun, Ma Zilong, Liao Yinfei

Physicochemical Problems of Mineral Processing

2019

Vol. 55, iss. 1

97--107

The adsorption mechanism of Al(III) and Fe(III) ions on bastnaesite surfaces was investigated by a combination of DFT calculation, XPS analysis, adsorption isotherm study and adsorption kinetic investigations. DFT calculation results indicated that ≡CeOH0 and ≡CO3H0 are primary functional groups on bastnaesite surfaces. XPS analysis reveals that Al(III) and Fe(III) ions adsorbed onto the bastnaesite surfaces through the interaction between aluminium/iron hydroxide species and oxygen atoms of surface ≡CeOH0 groups. No interaction between aluminium/iron hydroxide species and ≡CO3H0 groups was detected. Adsorption isotherm studies demonstrated that the adsorption data of Al(III) and Fe(III) ions is fitted relatively well by Freundlich equations, the adsorption kinetic characteristics fitted to pseudo-second order model. Freundlich constants suggested favorable process for Al(III) and Fe(III) ions adsorption, and each adsorbed metal hydroxide specie complex with at least two oxygen atoms of surface ≡CeOH0 groups.

Solubility of Eskisehir thorium/rare earth ores in sulphuric and nitric acids

Kursun I., Tombal T. D., Terzi M.

Physicochemical Problems of Mineral Processing

2018

Vol. 54, iss. 2

476--483

Nuclear energy is considered as one of the most important energy resources in the world. Thorium (Th) has a significant potential to be used in electricity production by nuclear energy since its existence is not depended on the presence of another radioactive elements, and it has larger potential reserves than uranium. Bastnaesite ((Ce, La)CO3F) is one of the minerals from which Th can be economically extracted. In this study, solubility of bastnaesite containing ore obtained from Eskisehir, Turkey was investigated by leaching with H2SO4 and HNO3 in terms of leaching performance of thorium and some rare-earth elements (Ce, Nd, La). In this context, representative samples were taken from three different areas in Eskisehir-Kizilcaoren region, and a composite sample was prepared to be used for the leaching experiments. The effects of several parameters such as the solid ratio, leaching time, acid amount and pulp temperature, on dissolution efficiencies of Th, Nd, Ce and La was investigated. The best results were obtained using 3.42 mol/dm3 HNO3, solid–to–liquid ratio of 35%, 120 min leaching time and 60 oC temperature. Under these optimum conditions, the dissolution efficiencies of Th, Ce, Nd, and La were obtained as 94%, 82%, 77% and 70%, respectively.