|
|||||
|
|
Corrosion of tin in citric acid solution and the effect of some inorganic anions |
|
| Authors: | S S Abdel Rehim S M Sayyah M M El Deeb |
| Affiliation: | a Department of Chemistry, Faculty of Science, Ain Shams University, Cairo, Egypt b Department of Chemistry, Faculty of Science, Cairo University, Beni-Suef branch, Beni-Suef, Egypt |
| Abstract: | The corrosion behaviour of tin in different concentrations of citric acid solutions (0.3–1.0 M, pH=1.8) was studied at 30 °C by potentiodynamic technique. The E/I profiles exhibit an active passive behaviour. The active dissolution involves one anodic peak A associated with a dissolution of the metals as Sn(II) species. The passivity is due to the formation of thin film of SnO2 and or Sn(OH)4 on the anode surface. The cathodic sweep shows a small peak C related to the reduction of the passive film. The peak current density Ip of peak A increases with increasing both acid concentration and sweep rate. The effects of adding increasing concentrations of Na2CrO4, NaMoO4, NaNO3 and NaNO2 on the corrosion of tin in 0.5 M citric acid at 30 °C were investigated. Both CrO42? and MoO42? ions inhibit the corrosion of tin and the extent of inhibition enhances with their concentrations. Addition of either NO3? or NO2? accelerates the corrosion of tin. NO3? ions are more aggressive than NO2? ions. |
| Keywords: | Corrosion Tin Citric acid Inorganic additions |
| 本文献已被 ScienceDirect 等数据库收录！ | |
