Synchrotron XPS studies of solution exposed chalcopyrite, bornite, and heterogeneous chalcopyrite with bornite

Acres, Robert G.; Harmer, Sarah L.; Beattie, David A.

doi:10.1016/j.minpro.2009.11.006

Cited by 100 publications

(53 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…structure. The reason behind the higher binding energy of 161.6 eV than that observed in the literature is the increased coordination number of S atom [60]. The additional contribution obtained at 162.8 eV represents the formation of polysulfide (S n 2 − , where 2 ≤ n ≤ 8) [61] which is generally observed in binding energy range between about 162.0 eV (disulfide) and 164.0 eV (elemental sulfur) [62].…”

Section: Chemical Analysismentioning

confidence: 79%

See 1 more Smart Citation

Growth of Cu2ZnSnS4 absorber layer on flexible metallic substrates for thin film solar cell applications

et al. 2015

View full text Add to dashboard Cite

In this work, Cu 2 ZnSnS 4 (CZTS) absorber layers were fabricated using a two-stage process. Sequentially deposited Cu-Zn-Sn thin film layers on metallic foils were annealed in an Ar + S 2(g) atmosphere. We aimed to investigate the role of flexible titanium and molybdenum foil substrates in the growth mechanism of CZTS thin films. The Raman spectra and X-ray photoelectron spectroscopy analyses of the sulfurized thin films revealed that, except for the presence of Sn-based secondary phases, nearly pure CZTS thin films were obtained. Additionally, the intense and sharp X-ray diffraction peak from the (112) plane provided evidence of good crystallinity. Electron dispersive spectroscopy analysis indicated sufficient sulfur content but poor Zn atomic weight percentage in the films. Absorption and band-gap energy analyses were carried out to confirm the suitability of CZTS thin films as the absorber layer in solar cell applications. Hall effect measurements showed the p-type semiconductor behavior of the CZTS samples. Moreover, the back contact behavior of these metallic flexible substrates was investigated and compared. We detected formation of cracks in the CZTS layer on the molybdenum foils, which indicates the incompatibility of molybdenum's thermal expansion coefficient with the CZTS structure. We demonstrated the application of the magnetron sputtering technique for the fabrication of CZTS thin films on titanium foils having lightweight, flexible properties and suitable for roll-to-roll manufacturing for high throughput fabrication. Titanium foils are also cost competitive compared to molybdenum foils.

show abstract

Section: Chemical Analysismentioning

confidence: 79%

“…13(d) consists of three doublets for Ti-CZTS. The S 2p 3/2 peaks at 160.6 eV [58] and 161.0 eV [59] indicate monosulfide whereas the other at 162.2 eV represents disulfide (S 2 2− ) [60]. ) structure.…”

Section: Chemical Analysismentioning

confidence: 99%

Growth of Cu2ZnSnS4 absorber layer on flexible metallic substrates for thin film solar cell applications

et al. 2015

View full text Add to dashboard Cite

show abstract

“…In order to develop proper alternatives to avoid surface passivation and enhance the hydrometallurgical efficiency, various strategies, including surface-sensitive X-ray photoelectron spectroscopy (XPS) synchrotron-based techniques [15][16][17][18] have been attempted to investigate the surface products.…”

Section: Introductionmentioning

confidence: 99%

The Influence of Impurity Monovalent Cations Adsorption on Reconstructed Chalcopyrite (001)-S Surface in Leaching Process

Wei

Xiao

et al. 2016

Minerals

View full text Add to dashboard Cite

Hydrometallurgical processing of chalcopyrite is hindered predominantly due to the passivation layers formed on the chalcopyrite surface. However, the effects of impurity cations released from the gangue are not yet well understood. Density functional theory (DFT) calculations were carried out to investigate monovalent cations of Na + and K + on chalcopyrite (001)-S surface using Materials Studio. The results show that the 3d orbital of Fe and 3p orbital of S predominantly contribute to their activities during chalcopyrite oxidation and dissolution processes. In addition, SO 4 2− is more likely to be adsorbed on one Fe site in the presence of Na + , while it is preferentially adsorbed on two Fe sites in the presence of K + . However, the adsorption of both Na 2 SO 4 and K 2 SO 4 on the chalcopyrite (001)-S surface contributes to the breakage of S-S bonds, indicating that the impurity cations of Na + and K + are beneficial to chalcopyrite leaching in a sulfuric environment. The adsorption energy and partial density of states (PDOS) analyses further indicate that the adsorption of Na 2 SO 4 on chalcopyrite (001)-S surface is favored in both -BB (bidentate binuclear ) and -BM (bidentate mononuclear) modes, compared to the adsorption of K 2 SO 4 .

show abstract

“…Al-Harahsheh et al (2006) also found that, when chalcopyrite was in intimate contact with pyrite, it experienced an enhanced oxidation compared to when there was no contact with pyrite. Acres et al (2010) studied the oxidation and leaching of heterogeneous chalcopyrite with bornite by using Synchrotron X-ray Photoelectron Spectroscopy (SXPS). It was found that the presence of bornite in intimate contact with chalcopyrite resulted in fewer hydrophobic polysulfide species and more hydrophilic sulphate species at the chalcopyrite surface after oxidation in flotation related conditions.…”

Section: Galvanic Interaction Between Different Sulphide Mineralsmentioning

confidence: 99%

“…The doublet at 162.7 eV can be attributed to the formation of polysulphide from the oxidation of both sulphide minerals (Buckley andWoods 1984, Smart et al 1999). An energy loss (EL) feature has been fitted at approximately 164.1 eV, which is associated with S 3p to Fe 3d excitation (Harmer et al 2004, Acres et al 2010. Based on the type of surface oxidation species, the following reactions on chalcopyrite surfaces are proposed:…”

Section: Flotation Of Chalcopyritementioning

confidence: 99%

The effect of regrinding chemistry and particle breakage mechanisms on subsequent cleaner flotation

Chen¹

View full text Add to dashboard Cite

Regrinding rougher flotation concentrates is typically used to liberate valuable minerals from gangue prior to the cleaner separation stage in processing of low grade ores. Compared to the rougher flotation after primary grinding, it is usually more challenging to achieve a satisfactory performance in post-regrind cleaner flotation especially when fine particles are generated. One main factor which results in this reduction in flotation is the unsuitable particle surfaces produced after regrinding. However, this factor is not usually considered when designing and optimizing the regrinding process.Extensive studies have demonstrated that grinding chemistry can influence mineral floatability.However, earlier studies focused on primary grinding and rougher flotation rather than regrinding and cleaner flotation. In addition, different types of regrind mills are used in industry, and these provide different particle breakage mechanisms which may also influence mineral floatability.Therefore, the overall objective of this thesis study is to investigate the effects of regrinding chemistry and particle breakage mechanisms on the cleaner flotation. The implementation of regrinding in the copper and pyrite flotation circuits at Telfer gold mine was taken as a case study and four research areas were addressed with the objective of developing fundamental understanding to provide practical guidance for the plant operation. The four areas investigated are:1. Effect of regrinding chemistry on copper activation of pyrite and its flotation; 2. Separation of different copper sulphide minerals from pyrite after regrinding; 3. Importance of pulp chemistry during regrinding rougher concentrates; 4. Effect of particle breakage mechanisms on subsequent flotation.In this study, it was found that copper activation of pyrite and its flotation in the cleaner stage were affected by regrinding. In general, a decrease in surface concentration of collectors due to the increased surface area after regrinding contributed to the low pyrite recovery in the cleaner. Surface analysis revealed that both the surfaces that were carried from the rougher flotation concentrate and those which were freshly created were modified by the strong electrochemical reactions occurring inside the regrind mill. Stainless steel media promoted pyrite oxidation, especially on the copper activated surfaces. Mild steel media produced a greater amount of iron oxidation species which could adsorb on the carried surfaces. It was also found that mild steel media generated a reducing condition which favoured the copper activation on the freshly created surfaces.ii The research has also shown that the separability of chalcopyrite and chalcocite from pyrite was significantly different after regrinding, which was related to their electrochemical properties.Chalcocite was more active and therefore presented a stronger galvanic interaction with pyrite.Consequently chalcocite was more oxidised, which not only depressed its flotation but also produced sufficient copper ions...

show abstract

Synchrotron XPS studies of solution exposed chalcopyrite, bornite, and heterogeneous chalcopyrite with bornite

Cited by 100 publications

References 37 publications

Growth of Cu2ZnSnS4 absorber layer on flexible metallic substrates for thin film solar cell applications

Growth of Cu2ZnSnS4 absorber layer on flexible metallic substrates for thin film solar cell applications

The Influence of Impurity Monovalent Cations Adsorption on Reconstructed Chalcopyrite (001)-S Surface in Leaching Process

The effect of regrinding chemistry and particle breakage mechanisms on subsequent cleaner flotation

Contact Info

Product

Resources

About