The effects of sulphate ions and temperature on the leaching of pyrite. 1. Electrochemistry

Nicol, M.J.; Miki, Hajime; Zhang, Suchun; Basson, Petrus

doi:10.1016/j.hydromet.2013.01.010

Cited by 13 publications

(5 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A similar effect was observed in a sulfate system but not explained in a recent publication (Nicol et al, 2013). Potentiostatic measurements were therefore made on pyrite, enargite and platinum electrodes in a solution of 3 g/L copper(II) in the base electrolyte.…”

Section: Mass Transfer Effectssupporting

confidence: 61%

Cathodic reduction of iron(III) and copper(II) on various sulfide minerals in chloride solutions

2016

Self Cite

View full text Add to dashboard Cite

A comparative study of the electrochemical reduction of iron(III) and copper(II) ions on selected sulfide minerals in concentrated chloride solutions has been carried out as part of a broader study of the kinetics of the leaching of chalcopyrite, covellite, enargite and pyrite under chloride heap leaching conditions. Mixed potential, cyclic voltammetric and potentiostatic measurements have been made using rotating disk electrodes of massive mineral samples. For comparative purposes, arsenopyrite, platinum and gold electrodes have also been used under the same conditions. The mixed potentials of the various minerals in solutions containing 4.2 mol/L sodium chloride, 0.1 mol/L hydrochloric acid and 0.054 mol/L iron(III) and/or 0.047 mol/L copper(II) ions at 25 o C vary with time depending on the mineral reactivity. The difference between the mixed potentials and the solution potentials provide qualitative indications of mineral reactivity to dissolution with iron(III) or copper(II) as oxidants. Cyclic voltammetry conducted at potentials negative to the mixed potentials at slow sweep rates after the mixed potential measurements has shown variable reactivity of the minerals for reduction of iron(III) and copper(II) ions. The data has been analysed in terms of electrochemical kinetics using a modified Butler-Volmer approach that takes into account mass transport of the oxidized and reduced species and anodic oxidation of the minerals. The electrochemical rate constant derived from a fit of the data to the rate

show abstract

Section: Mass Transfer Effectssupporting

confidence: 61%

Cathodic reduction of iron(III) and copper(II) on various sulfide minerals in chloride solutions

2016

Self Cite

View full text Add to dashboard Cite

show abstract

“…After the reaction with pyrite, Fe 3+ was reduced to Fe 2+ , but the Fe 2+ oxidation by O 2 is very slow. The rate of pyrite dissolution decreases with increased sulfate concentration and ferrous concentration, as verified by an electrochemical method [29,30]. Luckily, these inoculated iron oxidizing acidophiles, dominated by At.…”

Section: Microbial Community and Activitymentioning

confidence: 77%

Industrial Heap Bioleaching of Copper Sulfide Ore Started with Only Water Irrigation

et al. 2021

View full text Add to dashboard Cite

Sulfuric acid solution containing ferric iron is the extractant for industrial heap bioleaching of copper sulfides. To start a heap bioleaching plant, sulfuric acid is usually added to the irrigation solution to maintain adequate acidity (pH 1.0–2.0) for copper dissolution. An industrial practice of heap bioleaching of secondary copper sulfide ore that began with only water irrigation without the addition of sulfuric acid was successfully implemented and introduced in this manuscript. The mineral composition and their behavior related to the production and consumption of sulfuric acid during the bioleaching in heaps was analyzed. This indicated the possibility of self-generating of sulfuric acid in heaps without exogenous addition. After proving by batches of laboratory tests, industrial measures were implemented to promote the sulfide mineral oxidation in heaps throughout the acidifying stages, from a pH of 7.0 to 1.0, thus sulfuric acid and iron was produced especially by pyrite oxidation. After acidifying of the heaps, adapted microbial consortium was inoculated and established in a leaching system. The launch of the bioleaching heap and finally the production expansion were realized without the addition of sulfuric acid, showing great efficiency under low operation costs.

show abstract

“…In order to reveal the nature of such electrochemical corrosion, it is firstly located that the chemical reaction behavior of sulfide minerals and OMN with the properties of semiconductors in the leaching process is similar to the battery corrosion process. 104 The main structure of OMN is MnO 2 , and MnO 2 has received much attention as a representative positive electrode material. 105 In the structure of MnO 2 , the [MnO 6 ] octahedra can be connected with adjacent octahedral units by co-edges or co-angles.…”

Section: Basis Of Corrosion Cellsmentioning

confidence: 99%

“…The nature of OMN bioleaching is a redox reaction between microorganisms and minerals in concert. In order to reveal the nature of such electrochemical corrosion, it is firstly located that the chemical reaction behavior of sulfide minerals and OMN with the properties of semiconductors in the leaching process is similar to the battery corrosion process 104 …”

Section: Progress and Mechanismsmentioning

confidence: 99%

Bioleaching of oceanic manganese nodules: Current progress and future prospects

Xue

Feng

et al. 2023

Asia-Pacific J Chem Eng

View full text Add to dashboard Cite

The extraction of manganese elements and other strategic elements from oceanic manganese nodules has become a strategic decision to ensure the security of global metal resources and the high‐quality green development of metal resource processing and metallurgy industry due to the gradual depletion of high‐quality terrestrial metal resources and the increase of difficult‐to‐select and difficult‐to‐smelt deposits. In order to achieve the enrichment and separation of diverse elements within oceanic manganese nodules, it is imperative to initiate chemical reactions that facilitate the breakdown of complex oxides, particularly manganese dioxide. Bioleaching is a viable treatment option for oceanic manganese nodules with low operating costs and environmental damage. However, the mechanism of oceanic manganese nodules bioleaching is not fully studied, and the prospect of technology development is uncertain. We have reviewed five influencing factors on bioleaching of oceanic manganese nodules: mineralogical characteristics, chemical reaction equilibrium, thermodynamic characteristics, microbial properties, and operational variables. It then makes new development recommendations and technological system suggestions for the future improvement of oceanic manganese nodule bioleaching, primarily focusing on the development of new technologies for challenging to select and difficult to smelt ores, the practicality of strategic energy metal development, the cell design and its materials revolution, environmental protection and management, and all‐round resource utilization. Solving the above critical technical issues will boost the high‐quality development of metal industry and environmental protection.

show abstract

The effects of sulphate ions and temperature on the leaching of pyrite. 1. Electrochemistry

Cited by 13 publications

References 18 publications

Cathodic reduction of iron(III) and copper(II) on various sulfide minerals in chloride solutions

Cathodic reduction of iron(III) and copper(II) on various sulfide minerals in chloride solutions

Industrial Heap Bioleaching of Copper Sulfide Ore Started with Only Water Irrigation

Bioleaching of oceanic manganese nodules: Current progress and future prospects

Contact Info

Product

Resources

About