Anodic process on Cu−Al alloy in KF−AlF3−Al2O3 melts and suspensions

Padamata, Sai Krishna; Yasinskiy, Andrey; Polyakov, P. V.

doi:10.1016/s1003-6326(20)65307-9

Cited by 15 publications

(6 citation statements)

References 30 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…133 Solheim suggested that the alumina particle size should be about 5 to 10 μm to promote the anode consumption of alumina. A similar conclusion was drawn by Yasinskiy et al 134 and Padamata et al, 25 where the alumina particle size should be around 5 μm. Moreover, they suggest that the alumina volume fraction in the electrolyte should be not more than 12 vol% for the proper functioning of the anode.…”

Section: Vertical Electrode Cellsupporting

confidence: 83%

“…Padamata et al investigated the effect of alumina volume fraction in KF-AlF 3 -Al 2 O 3 (CR = 1.3) melt on the electrochemical behaviour and oxides layers formed on the Cu 90 Al 10 anodes. 25 The anodic potential ranged between 2.5 and 3.5 V (vs Al/Al 3+ ) for a volume fraction between 0 and 15% for a current density of 0.4 A cm −2 at 750 °C. XRD results suggest the CuO and Cu 2 O phase concentration in the oxide layer with an increase in alumina volume fraction while the limiting current decreased.…”

Section: Inert Anode Materialsmentioning

confidence: 95%

“…Padamata et al 25 studied the anodic behaviour of aluminium bronze anodes during galvanostatic polarisation (anode current density = 0.4 A cm −2 ) in KF-AlF 3 -Al 2 O 3 saturated and suspension melts. The anodic potential constantly changes with time in saturated melts, and a constant fluctuation in potential can be observed, which is associated with oxygen evolution and a sudden drop in the potential could do due to the delamination of oxide layer (Fig.…”

Section: Vertical Electrode Cellmentioning

confidence: 99%

See 2 more Smart Citations

Review—Primary Production of Aluminium with Oxygen Evolving Anodes

Padamata

Singh

Haarberg

et al. 2023

J. Electrochem. Soc.

Self Cite

View full text Add to dashboard Cite

Due to environmental and economic concerns, carbon-free aluminium production has been an ultimate goal for aluminium industries. For the past few decades, a considerable amount of research has been conducted to find an inert anode material that could replace the consumable carbon anodes for aluminium electrolysis. Anodic materials such as metals, ceramics, and cermets have been studied extensively. All these anode materials have their advantages and disadvantages. However, metal alloys have proven effective because of their resistance to high-temperature corrosion and their ability to produce a protective oxide layer. For a successful adaptation of metallic anodes into the aluminium electrolysis cell, an electrolyte with a low operating temperature and high alumina solubility with good electrical conductivity is required. A wettable cathode with a shorter anode-to-cathode distance is preferred to compete with the Hall-Héroult process in terms of energy requirements. This review discusses the research progress on inert anodes, wettable cathodes, and electrolytes.

show abstract

Section: Vertical Electrode Cellsupporting

confidence: 83%

Section: Inert Anode Materialsmentioning

confidence: 95%

Section: Vertical Electrode Cellmentioning

confidence: 99%

See 1 more Smart Citation

Review—Primary Production of Aluminium with Oxygen Evolving Anodes

Padamata

Singh

Haarberg

et al. 2023

J. Electrochem. Soc.

Self Cite

View full text Add to dashboard Cite

show abstract

“…Electrochemical behaviour of Cu-Al based alloys with compositions 86Cu-9Al-5Fe, 90Cu-10Al and 88.3Cu-10Al-1.7Be was tested in KF -AlF3 -Al2O3 melts and suspensions [41][42][43]. The influence of alumina volume fraction and the composition of anode were characterised by stationary and non-stationary polarization.…”

Section: Cu -Al Alloymentioning

confidence: 99%

An update on inert anodes for aluminium electrolysis

Yasinskiy¹,

Padamata²,

Polyakov³

et al. 2020

nfm

View full text Add to dashboard Cite

This update includes the literature related to the inert anodes which were published in the past decade. The metallic anodes are widely regarded as promising candidates to replace the carbon anodes due to its attractive properties like good electrical conductivity, easy to manufacture and high resistance to high thermal shocks. The metals have been tested in pure state and alloy (binary, ternary) form. The oxide scale formed on the anode surface acts as a barrier between the electrolyte and the anode which protects the anode from being dissolved. The layer of molten fluorides is formed between the scale and the metal anode after a certain time of polarization and the oxide scale acts as a bipolar electrode. Metal like Cu is reduced at the internal side of the scale. This paper elaborates the effects of various parameters on the performance of the anode. Cu-based alloys (Cu -Ni-Fe and Cu-Al) have shown promising results and could perform well in low-temperature electrolytes. It has been well established that the Cu content in Cu-Ni-Fe and Cu-Al alloys plays a major role in the metal dissolution as the CuO/Cu2O scales formed on the outer layer act as a sacrificial one. The corrosion rate of an anode can be reduced by decreasing the operating temperature which is possible by using the KF-AlF3 melts. The use of suspensions can increase the purity of the produced metal by stopping the anode products to come in contact with cathode metal.Many industries including RUSAL and ELYSIS are still conducting a considerable amount of research to develop an inert anode and are expecting to have a carbon-free cell in the nearest future.

show abstract

“…Compared to ceramics and cermets, metallic anodes have shown promising results due to their high electrical conductivity, thermal shock resistance, robustness, ease of fabrication and easy electrical connectivity. 4 Cu-Ni-Fe [6][7][8][9][10] and Cu-Al [11][12][13] based alloys have extensively been studied in recent years in low-temperature electrolytes between 973 and 1123 K. This work is done in collaboration with Arctus Metals and IceTec in Iceland, who are developing an inert anode process. 10 The presence of Cu in the alloy is vital as the Cu oxides formed on the outer layer of the alloy prevent electrolyte penetration into the electrode.…”

mentioning

confidence: 99%

Anodic Behaviour of Ni₄₂Fe₃₈Cu₂₀ Electrode in Molten Fluoride Salts

Sævarsdóttir

Haarberg

Bourmaud

et al. 2023

J. Electrochem. Soc.

Self Cite

View full text Add to dashboard Cite

The anodic behaviour of Ni42Fe38Cu20 alloy at different sodium-potassium-cryolite-based electrolyte compositions was examined by chronopotentiometry, chronoamperometry, and linear sweep voltammetry at 1098 K for different electrolyte compositions. Steady-state anodic polarisation curves show that the anodic overpotential in electrolytes with molar ratio CR=(NaF+KF)/AlF3=1.4 is significantly less than in electrolyte with CR=1.3. Short-term galvanostatic polarisation curves indicate that the potential difference between the anode and reference electrode (Al) was stable in electrolytes with CR=1.4 and potassium ratio KR=KF/(KF+NaF)=0.3 and CR=1.4 KR=0.35. The linear sweep voltammetry method indicates the presence of a diffusion-controlled reaction at a potential below the onset of oxygen evolution, which can be attributed to oxide formation. Tafel curves indicate the presence of the reactions below the potential of oxygen evolution but show a similar overpotential level for the oxygen-evolving reaction as for carbon anodes. Furthermore, the effect of pre-oxidation and influence of consistent polarisation on the anode performance was explored. Pre-oxidised anodes have better stability and lower exchange current density in similar experimental conditions compared to untreated anodes. It was also observed that leaving anodes unpolarised could lead to their instability and fluoridation of both types of anodes, with less severe effect on the pre-oxidised anode.

show abstract

Anodic process on Cu−Al alloy in KF−AlF3−Al2O3 melts and suspensions

Cited by 15 publications

References 30 publications

Review—Primary Production of Aluminium with Oxygen Evolving Anodes

Review—Primary Production of Aluminium with Oxygen Evolving Anodes

An update on inert anodes for aluminium electrolysis

Anodic Behaviour of Ni₄₂Fe₃₈Cu₂₀ Electrode in Molten Fluoride Salts

Contact Info

Product

Resources

About

Anodic process on Cu−Al alloy in KF−AlF3−Al2O3 melts and suspensions

Cited by 15 publications

References 30 publications

Review—Primary Production of Aluminium with Oxygen Evolving Anodes

Review—Primary Production of Aluminium with Oxygen Evolving Anodes

An update on inert anodes for aluminium electrolysis

Anodic Behaviour of Ni42Fe38Cu20 Electrode in Molten Fluoride Salts

Contact Info

Product

Resources

About

Anodic Behaviour of Ni₄₂Fe₃₈Cu₂₀ Electrode in Molten Fluoride Salts