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Insights into the depression effect and adsorption mechanism of HACC on chalcopyrite surface in Cu-Mo flotation separation

Li Mingyang, Zhang Pengpeng, Gao Xiangpeng, Huang Lingyun

Physicochemical Problems of Mineral Processing

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2023

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Vol. 59, iss. 6

art. no. 172481

EN

In this study, hydroxypropyltrimethyl ammonium chloride chitosan (HACC) was first introduced as a depressant during separating chalcopyrite from molybdenite (Cu-Mo). The selective effects of HACC on the separation of Cu-Mo were conducted by single-mineral flotation experiments. The findings from this study revealed that HACC helped separate Cu and Mo efficiently at pH 6 with 8 mg/dm3 of HACC, resulting in 76.22% and 5.38% of Mo and Cu flotation recovery, respectively. The adsorption mechanism of HACC was investigated via zeta potential, adsorption density, and contact angle measurement along with FT-IR and XPS analyses. The contact angle and adsorption density measurements offer indisputable proof that HACC can adsorb on the surface of chalcopyrite. Furthermore, FT-IR and XPS analyses confirm that N atoms in quaternary ammonium groups of HACC interact with Cu sites on the surface of chalcopyrite. The findings also suggest that HACC adsorbs on the surface without significantly impacting molybdenite. All these results confirm that HACC can be an effective chalcopyrite depressant.

2

Synthesis of a novel hydroxamic acid flotation collector and its flotation separation of malachite against quartz

Sun Xin, Huang Lingyun, Wu Dandan, Hu Bo, Zhang Mei, Li Yaming, Tong Xiong

Physicochemical Problems of Mineral Processing

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2022

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Vol. 58, iss. 4

art. no. 149427

EN

This paper proposes a promising chelating collector, phenyl propyl hydroxamic acid (BPHA), to directly float malachite for the separation of malachite against quartz. The flotation performance and mechanism was investigated via microflotation tests, as well as through contact angle, Scanning Electron Microscopeand Energy Dispersive Spectrometer (SEM–EDS), zeta potential, adsorption capacity, Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) analyses. The results of microflotation tests showed that BPHA has a strong ability to collect malachite and a significant selectivity against quartz. The contact angle tests showed that BPHA effectively adsorbed onto the mineral surface and could improve the hydrophobicity of the malachite surface. SEM–EDS and adsorption capacity analyses further indicated that BPHA adsorbed onto the surface of malachite. The FR-IR results suggested that BPHA could react with Cu2+ ions and facilitate strong chemical adsorption onto the surface of malachite. Furthermore, zeta potential and XPS analyses provided clear evidence that BPHA exhibited a stronger affinity for malachite and a weaker interaction with quartz.

3

Insight into the effect of galvanic interactions between sulfide minerals on the floatability and surface characteristics of pyrite

Yang Bo, Tong Xiong, Xie Xian, Huang Lingyun

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 2

24--33

EN

Complex sulfide ores are usually found as a mixture of various sulfide and gangue minerals, and froth flotation is the predominant method for the selective separation of sulfide minerals. Adherence and contact between sulfide minerals are inevitable during froth flotation, and galvanic interactions between sulfide minerals will occur because of differences in rest potentials. However, the effect of these galvanic interactions on the selective flotation of sulfide minerals have been rarely studied. In this work, the effect of the galvanic interaction between pyrite and sphalerite on the flotation behavior and surface characteristics of pyrite was investigated by micro-flotation tests, collector adsorption tests, electrochemical techniques and XPS (X-ray photoelectron spectroscopy) surface analysis. The micro-flotation tests indicated that the floatability of pyrite decreased in the pH range of 4.0 to 9.5 and increased under strongly alkaline pH conditions (pH > 10) due to the galvanic interaction. The collector adsorption results demonstrated that the adsorption capacity of the collector on the pyrite surface was significantly reduced because of the galvanic interaction between pyrite and sphalerite. The electrochemical measurements revealed that the decrease in the oxidation current of xanthates to dixanthogen was responsible for the decreasing adsorption capacity of the collector on the pyrite surface. The XPS results indicated that the formation of the S"O$ "% oxidation product on the pyrite surface decreased at a strongly alkaline pH due to the galvanic interaction. Therefore, pyrite floatability improved at an alkaline pH. These results consistently showed that the galvanic interaction between pyrite and sphalerite had an important influence on the floatability and surface characteristics of pyrite.

4

DFT and TOF-SIMS study of the interaction between hydrogen sulfide ion and malachite (–201) surface

Mao Yingbo, Wu Dandan, Huang Lingyun

Physicochemical Problems of Mineral Processing

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2021

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Vol. 57, iss. 5

71--79

EN

In this paper, the mechanism of interaction between hydrogen sulfide ions and malachite was investigated using density functional theory (DFT) calculations and time of flight secondary ion mass spectrometry (TOF-SIMS). The DFT calculations showed that HS− adsorption on the malachite (−201) surface was stronger than that of S adsorption resulting from the higher number of electron transfers in the solution which accelerated the sulfidation reaction rate. Density of states (DOS) analysis showed that the near Fermi level was jointly contributed to by the Cu 3d, O 2p, O 2S, and S 3P orbits after adsorption of HS− on the malachite (–201)surface. It was found that the 2p orbital of O and the 3p orbital of S overlapped, indicating that S not only reacted with Cu, but also with O. The TOF-SIMS detected S− and CuS2− fragment ion peaks in the 0−150 m/z negative segment of mass spectra. TOF-SIMS also showed that copper sulfide films of certain thicknesses were formed, demonstrating the effectiveness of hydrogen sulfide sulfidation in flotation processes.

5

Evaluation of ammonium citrate tribasic as a leaching reagent for lead-bearing ore

Liu Junbo, Li Shimei, Zhao Biao, Deng Jianying, Huang Lingyun, Zhou Yuanyuan, Chen Cong, Liu Quanjun

Physicochemical Problems of Mineral Processing

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2019

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Vol. 55, iss. 3

689--700

EN

In this study, the leaching process of a lead-bearing ore, consisting mainly of cerussite, in an ammonium citrate tribasic medium was investigated. The parameters including temperature, reagent concentration, particle size, and stirring speed were examined. During leaching process, the lead conversion rate increased with an increase in reagent concentration, reaction temperature, and stirring speed, and a decrease in particle size. The results show that about 95% of lead content was extracted from the samples with particle size range of +75-96 μm after 21 min leaching in 1.25 mol/L ammonium citrate tribasic solution at 800 r/min and 40°C. It was found that the leaching reaction followed the shrinking core model. The results indicated that ammonium citrate tribasic could be used as an effective leaching reagent for extracting lead from lead oxide ore.