Solution chemistry of carbonate minerals and its effects on the flotation of hematite with sodium oleate

The effects of carbonate minerals（dolomite and siderite） on the flotation of hematite using sodium oleate as a collector were investigated through flotation tests, supplemented by dissolution measurements, solution chemistry calculations, zeta-potential measurements, Fourier transform infrared（FTIR） spectroscopic studies, and X-ray photoelectron spectroscopy（XPS） analyses. The results of flotation tests show that the presence of siderite or dolomite reduced the recovery of hematite and that the inhibiting effects of dolomite were stronger. Dissolution measurements, solution chemistry calculations, and flotation tests confirmed that both the cations（Ca^（2＋） and Mg^（2＋）） and CO_3^（2＋）ions dissolved from dolomite depressed hematite flotation, whereas only the 23CO-ions dissolved from siderite were responsible for hematite depression. The zeta-potential, FTIR spectroscopic, and XPS analyses indicated that Ca^（2＋）, Mg^（2＋）, and CO_3^（2-）（HCO_3^-） could adsorb onto the hematite surface, thereby hindering the adsorption of sodium oleate, which was the main reason for the inhibiting effects of carbonate minerals on hematite flotation.

Electrochemical and spectroscopic study of interfacial interactions between chalcopyrite and typical flotation process reagents

Comparative voltammetry and differential double-layer capacitance studies were performed to evaluate interfacial interactions between cnalcopyrite（CuFeS2） and n-isopropyl xanthate（X） in the presence of ammonium bisulfite/39wt%SO2 and caustic starch at different pH values.Raman spectroscopy,Fourier transform infrared（FTIR） spectroscopy,contact angle measurements,and microflotation tests were used to establish the type and extent of xanthate adsorption as well as the species involved under different mineral surface conditions in this study.The results demonstrate that the species that favor a greater hydrophobicity of chalcopyrite are primarily CuX and S^0,whereas oxides and hydroxides of Cu and Fe as well as an excess of starch decrease the hydrophobicity.A conditioning of the mineral surface with ammonium bisulfite/39wt%SO2 at pH 6 promotes the activation of surface and enhances the xanthate adsorption.However,this effect is diminished at pH ≥ 8,when an excess of starch is added during the preconditioning step.

STUDIES ON THE FROTH CHARACTERISTICS OF COMPOSITE COLLECTORS IN NONMETALLIC MINERAL FLOTATION

The flotation results of a phosphate ore are improved by replacing the conventional collectors of fatty acids with composite collectors. The synergistic effect on the froth characteristics in systems using composite collectors has then been studied, and the concept of 'mixed hemimicellae' has been proposed in the adsorption of composite collectors at the air/solution interfaces.

STUDY ON FLOTATION OF RARE EARTH MINERALS WITH P538 AND ITS MECHANISM

The properties and collecting ability of a new collector,monoalkyl ester phosphoric acid(P538),for the flotation of rare earth minerals are described in the paper.The mechanism of P538 adsorption on the surfaces of monazite or bastnaesite is explored by modern measuring techniques,such as IR and ESCA,etc.

Review of the research on the development and utilization of clay-type lithium resources

Since the demands for lithium have been in explosive growth recently and several great clay lithium resources were founded in China,the development and utilization of clay-type lithium resources become a hot topic.In order to provide a guidance for the concentration and extracting lithium of clay-type lithium resources,this review systematically summarized the main types and characteristics of clay-type lithium resources and the research status of lithium extraction from clay lithium resources.Meanwhile,the flotation research status of the main mineral of clay lithium ore was also summarized.Furthermore,we discussed the difficulties in the development and utilization of clay-type lithium ore and put forward the subsequent research orientation.This paper can provide a guidance for the con-centration and extracting lithium of clay-type lithium resources in the future.