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The effect of Al(III) and Fe(III) ions on the flotation behavior of Kfeldspar with sodium oleate as the collector

Yi Chen, Zhou Jikui, He Guichun, Hu Hongxi, Liu Chao, Yang Jiping, Lyu Xianjin

Physicochemical Problems of Mineral Processing

2023

Vol. 59, iss. 6

art. no. 174724

The present study investigates the effects and mechanisms of aluminum (Al(III)) and iron (Fe(III)) ions on the flotation efficiency of potassium feldspar (K-feldspar) within oleate collector systems. The study employs micro-flotation experiments, solution chemistry calculations, zeta potential measurements, and FT-IR and XPS analyses to demonstrate that Al(III) and Fe(III) ions can significantly improve the flotation recovery of K-feldspar by altering its surface charge, bonding properties, and adsorption modes. The study also develops adsorption models for the flotation of K-feldspar activated by Al(III) and Fe(III), revealing the synergistic impacts of metal ion hydrolysis products and sodium oleate in the formation of hydrophobic complexes.

First-principles calculations of electronic structure of rhodochrosite with impurity

He Guichun, Li Kun, Li Kun, Guo Tengbo, Li Shaoping, Huang Chaojun, Zeng Qinghua

Physicochemical Problems of Mineral Processing

2020

Vol. 56, iss. 1

195--203

The electronic structure of rhodochrosite containing impurity defects is studied by using the first principles density functional theory. The energy band structure, density of states and electronic distribution are calculated for rhodochrosite crystal models with various impurities (e.g., Cu, Ca, Mg, Zn, Fe). This paper discusses the effects of such defects on the electronic structure of rhodochrosite. The calculation results show that the impurity defects have a great impact on the surface electrical properties of rhodochrosite. For example, Ca and Mg impurities reduce the semiconductor width of rhodochrosite. Both Ca and Mg atoms in orbital bonding act as electron donors in which Ca3p and Mg2p orbits provide electrons while O2p orbits receive electrons. Moreover, the more number of valence electrons of Mn is the weaker covalent interaction between Mn and O atoms will be. Meanwhile, decrease of the total energy of rhodochrosite, makes the structure more stable. When Fe, Zn and Cu impurities are contained, the forbidden gap becomes narrower, which improves the conductivity of rhodochrosite. In addition, impurity bands will be formed in the 3d orbits of rhodochrosite as shown in its density of states, and the number of electrons in 3d orbits will increase. This weakens the covalence of O atoms, decreases the population values of O-Mn, increases the bond length, and enhances the ionicity of O-Mn bonds. The impurity of all defects considered in this study have shown an improved conductivity of rhodochrosite, and increased hole concentration of Mn atoms, which will be of great benefit to the adsorption of anionic collectors and enhance the electrochemical properties for rhodochrosite flotation process.