Anode Passivation in Copper Refining

Abe, Shin‐ichiro; Burrows, Brian; Ettel, V.

doi:10.1179/cmq.1980.19.3.289

Cited by 40 publications

(14 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In this process, pure copper is produced and also, valuable impurities are removed from the impure copper as anodic slime [1,2,4]. Copper anodes with a purity of 98.5 to 99.5% is used loss because the anode has to be removed and melted again [5][6][7][8][9][10][11][12][13].…”

Section: Introductionmentioning

confidence: 99%

Modeling and Optimization of Charge Materials Ranges in Converter Furnace with Enhanced Passivation Time in Copper Electrorefining Process: A Mixture Design Approach

Feizabad

Khayati

Hernashki

et al. 2021

IJE

View full text Add to dashboard Cite

In this study, the design of experiments is used to study and model the time of passivation in copper electrorefining as a function of the charge of melting furnace through the preparation of copper casting anodes. As a result of optimization for the proposed optimized anodes, the charge percent values of concentrate (Co), refinery scrap (RS), and non-refinery scrap (NRS) were proposed equals to 69.1, 0.574 and 30.32 (wt.%), respectively. Experimental data confirmed the enhanced passivation time of the proposed anode was 6520 s. Also, it was observed that the molar ratio of As/(Bi+Sb) and Ag/(Se+Te) are the key factors in passivation time. Finally, the relation of passivation time (seconds) with the charge of melting furnace is proposed as : t (s)= -3728.98 × Co + 4640.00 × RS + 3141.00 × NRS + 17763.27 × Co × RS + 25547.65 × Co × NRS -1758.00 × RS × NRS. Moreover, adding of As ingot in casting anodes as a dose dependent of non-refinery scrap portion in the input charge of the melting unit can effectively prolong the time of passivation.

show abstract

Section: Introductionmentioning

confidence: 99%

Modeling and Optimization of Charge Materials Ranges in Converter Furnace with Enhanced Passivation Time in Copper Electrorefining Process: A Mixture Design Approach

Feizabad

Khayati

Hernashki

et al. 2021

IJE

View full text Add to dashboard Cite

show abstract

“…Various researchers have aimed to resolve anode passivation, such as by forced electrolyte flow by using a rotating electrode 5) or pump, 6) the optimization of electrolyte composition 7,8) and solution temperature, 7) additives to electrolyte, 9,10) precipitation phase control at the anode, 11,12) and periodic reverse current. 13,14) Despite these efforts, electrorefining cannot be applied to low-grade copper that contains high levels of impurities from secondary resources.…”

Section: Introductionmentioning

confidence: 99%

Electrorefining Behavior of Copper Shot-Shaped Anode Containing High Levels of Platinum

2020

View full text Add to dashboard Cite

Increased amounts of secondary copper resources with higher levels of impurities are being fed to copper smelters. To avoid passivation problems, low-grade copper that is derived from secondary resources is dissolved in sulfuric-acid solution, and the dissolved copper is recovered by electrowinning. Electrowinning is disadvantageous because of its higher power consumption compared with electrorefining. Based on an electroplating technique that uses basket electrolysis with a ball-shaped anode and another experimental approach of copper-scrap electrorefining in a basket, we investigated an electrorefining method that uses small low-grade copper shots (diameter of several millimeters) as an anode. It is expected that the copper-dissolution ratio will be higher, even with a small elution depth, because of the small primary-anode size and the effect of the three-dimensional shape. In addition, the current density for a shot-shaped anode can be lower than that for a plate-shaped anode at the same current and for the same occupied area, and would result in the inhibition of passivation. Rotating-disk-electrode equipment was used in the electrolysis experiments. Single-layered copper shots that contained 0.9 « 0.2 mass% Pt (18 shots) in a platinum basket were used as an anode, and a copper rotating-disk electrode (7-mm diameter) was used as a cathode. The temporal changes in anode potential were measured at a constant current to investigate the electrolytic properties of a small shot-shaped anode during the electrorefining experiments. The current efficiency and final anode-dissolution ratio exceeded 90% up to an initial anode current density of ³673 A/m 2. Stable electrolysis could be carried out with a copper shot-shaped anode that contained high levels of platinum.

show abstract

“…In spite of the electrochemical nature of the problem, little information has been published on the anodic passivation of copper in industrial electrorefining conditions. Anodic passivation has been one of the major problems encountered by copper refineries [2][3][4].…”

Section: Introductionmentioning

confidence: 99%

Anodic behaviour of copper electrodes containing arsenic or antimony as impurities

1989

View full text Add to dashboard Cite

The anodic behaviour of three different copper electrodes in sulphuric acid medium was investigated using cyclic voltammetry in the potential range between the rest potential Ei= 0 = -0.34u and + 0.80 V vs the Hg, Hg2SO4/K 2 SO 4 saturated (MSE) reference electrode. Arsenic dissolved in the electrode mati'ix as well as oxygen dissolved in solution were found to delay passivation. The anodic peak current density was proportional to the square root of the potential sweep rate in two consecutive domains. An unusual break was observed for high scan rates ( > 50 mV s-1 ) and was attributed to an increase of the medium viscosity because of the large gradient of concentration near the electrode surface. On the other hand, current oscillations, usually observed in the anodic processes of metallic electrodes, have been studied as a function of the electrode vertical/horizontal positions. Gravity has been found to affect both the frequency and the amplitude of the oscillations. X-ray diffraction measurements conducted on galvanostatically electrolyzed samples revealed, besides copper metal, the presence of copper sulfate pentahydrate and trihydrate for Cu-As and Cu-Sb, respectively. SEM analysis showed the existence of preferential domains of white product on a darker background of metallic copper or copper oxides.

show abstract

Anode Passivation in Copper Refining

Cited by 40 publications

References 0 publications

Modeling and Optimization of Charge Materials Ranges in Converter Furnace with Enhanced Passivation Time in Copper Electrorefining Process: A Mixture Design Approach

Modeling and Optimization of Charge Materials Ranges in Converter Furnace with Enhanced Passivation Time in Copper Electrorefining Process: A Mixture Design Approach

Electrorefining Behavior of Copper Shot-Shaped Anode Containing High Levels of Platinum

Anodic behaviour of copper electrodes containing arsenic or antimony as impurities

Contact Info

Product

Resources

About