Anodic dissolution of pure aluminum during electrocoagulation process: Influence of supporting electrolyte, initial pH, and current density

Khaled Mansouri, Karim Ibrik, Nasr Bensalah, Ahmed Abdel-Wahab

Research output: Contribution to journalArticle

30 Citations (Scopus)

Abstract

In this work, effects of some experimental parameters (supporting electrolyte, initial pH, and current density) on aluminum corrosion and anodic dissolution of aluminum during electrocoagulation process were investigated. Potentiodynamic polarization tests, impedance spectroscopy measurements and potentisotatic current density transients were used to evaluate corrosion parameters and verify effects of supporting electrolyte and initial pH on aluminum corrosion. The presence of NaCl and Na2SO4 shifted the corrosion potential toward more cathodic potentials, indicating that corrosion of aluminum is catalyzed by the presence NaCl and Na 2SO4. On the contrary, the presence of NaH 2PO4 increased the corrosion potential, which indicates that the presence of NaH2PO4 inhibits the corrosion of aluminum. Galvanostatic electrolyses demonstrated that measured concentrations of aluminum exceeded theoretical values calculated using Faradays Law. The excess in dissolved aluminum produced during galvanostatic electrolyses is primary due to the chemical dissolution of aluminum, which is more significant at highly alkaline conditions. A final pH of value around pH 9 was observed in the presence of NaCl for pH values in the range pH 4-11 which can be explained by buffering effects of aluminum hydroxides.

Original languageEnglish
Pages (from-to)13362-13372
Number of pages11
JournalIndustrial and Engineering Chemistry Research
Volume50
Issue number23
DOIs
Publication statusPublished - 7 Dec 2011
Externally publishedYes

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ASJC Scopus subject areas

  • Chemistry(all)
  • Chemical Engineering(all)
  • Industrial and Manufacturing Engineering

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