Flotation behavior and electronic simulations of rare earth minerals in the presence of dolomite supernatant using sodium oleate collector

作     者：E.R.L.Espiritu G.R.da Silva D.Azizi F.Larachi K.E.Waters 

作者机构：Department of Mining and Materials Engineering McGill University Department of Chemical Engineering Université Laval 

出 版 物：《Journal of Rare Earths》 (稀土学报（英文版）)

年 卷 期：2019年第37卷第1期

页      面：101-112,M0005页

核心收录：

学科分类：0709[理学-地质学] 0819[工学-矿业工程] 0806[工学-冶金工程] 08[工学] 0708[理学-地球物理学] 0703[理学-化学] 

基　　金：supported by the Natural Sciences and Engineering Research Council of Canada(NSERC)and Niobec a Magris Resources Company through the Collaborative Research and Development Program(CRDPJ 453164-13) 

主　　题：Rare earth minerals Bastnasite Monazite Dolomite Sodium oleate DFT simulation 

摘      要：Common rare earth (RE) minerals, such as bastnasite and monazite, may be formed in deposits associated with carbonate gangue, such as calcite and dolomite. Sodium oleate is a widely used collector for the flotation of both RE and gangue minerals, which might, therefore, be an inefficient process due to the lack of selectivity of this collector. Since these minerals are also sparingly soluble in solution, they could release their constituent ions into the solution, which could affect the floatability of other minerals. In this study, the interactions of sodium oleate with bastn(a|¨)site and monazite in the presence of dissolved dolomite species have been investigated. Micro flotation tests were carried out to explore the effects of these dissolved species on the floatability of the RE minerals. Zeta potential measurements and XPS characterization were carried out to understand how the species affect the collector adsorption. To complement these characterizations, density functional theory (DFT) simulations were conducted to investigate the collector-mineral and collector-adsorbed species (on the mineral surface) *** results show that collector-dolomite interaction energy is greater than that of collector-adsorbed species, but lower than collector-monazite interaction energy, explaining the decrease in the minerals’recovery upon exposure to the dissolved mineral species. It is also shown that oleate ions (OI^-) have the strongest interaction with the minerals compared to other oleate species such as acid soap (HOI_2^-) and oleate dimer (Ol_2^(2-)). The behavior (strength and selectivity) of sodium oleate towards RE minerals and dolomite, as compared to other RE mineral collectors (such as aromatic hydroxamate), is attributed mainly to the collector s and the minerals structure. The long hydrocarbon chain of sodium oleate which imparts hydrophobic characteristic to the minerals, makes it stronger collector than ***, sodium oleate (wit