Table 2 Plants as corrosion inhibitors against aluminum corrosion
Study Conducted | Plant product | Solution | Effect of temperature on percentage inhibition efficiency | Effect of concentration on percentage inhibition efficiency | Methods | Adsorption | Reference |
|---|---|---|---|---|---|---|---|
Phoenix dactylifera reported as a good corrosion inhibitor for Al in NaOH solution by weight loss and PDP method. Obtained results show that inhibition efficiency increase with increasing temperature and concentration, followed the Temkin adsorption isotherm also | P. dactylifera, | NaOH | Increase | Increase | Weight loss, potentiodynamic polarization | Temkin adsorption isotherm | Rehan 2003 |
The extracts of Damsissa, Corchours oitorius reported as a good inhibitor for the corrosion of aluminum in aqueous sodium carbonate by the use of gasometry, potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS) | Extracts of Damsissa, Corchours oitorius | Sodium carbonate | Decrease | Increase | Gasometry, potentiodynamic polarization | Langmuir and Flory-Huggins | Abd-El-Nabey et al. 2012 |
Rosmarinus officinalis reported as a good corrosion inhibitor for aluminum in NaCl solution by the use of PDP method. Obtained result obeyed the Freundlich isotherm | R. officinalis | Chloride solution | Decrease with rise in temperature | Increase | Potentiodynamic polarization | Freundlich isotherm | Kliˇski´c et al. 2000 |
The dissolution of Al and Zn in HCl and NaOH medium were inhibited by H. subdariffa (Karkade) extract. Obtained results show that corrosion rate increase with increasing temperature but decrease with increasing concentration. Physical adsorption phenomena were observed | H. subhdariffa extract | HCl and NaOH | Decrease with rise in temperature | Increase | Weight loss and the galvanostatic polarization | Physical adsorption | El-hosary et al. 1972 |
Vernonia amygdalina reported as a fine corrosion inhibitor for aluminum in HCl and HNO3 medium by the use of weight loss method. But its inhibition performance was much better in HNO3 solution as compare to HCl medium | V. amygdalina | HNO3 and HCl | – | Increase | Weight loss method | – | Avwiri and Igho 2003 |
Saccharides (fructose and mannose) with the addition of ascorbic acid addition, reported as a good corrosion inhibitor for Al by the method of hydrogen evolution in alkaline medium | Saccharides (fructose and mannose) | Alkaline medium | – | – | Evolution of hydrogen | – | Muller 2002 |
The inhibitive effect of leaf extracts of Euphorbia hirta and Dialum guineense on aluminum alloy (AA8011) was reported in HCl solution by the use of gravimetric technique. The results indicate that both extracts worked as good inhibitors and inhibition efficiency improved with concentration | Leaf extracts of E. hirta and D. guineense | HCl | Decrease | Increase | Gravimetric technique | Langmuir adsorption isotherm | Anozie et al. 2011 |
The inhibition effect of Newbouldia laevis leaves extract reported as a good inhibitor on the corrosion of aluminum HCl and H2SO4 solutions by the use of gravimetric technique. Obtained results show that N. laevis inhibitor effect was more efficient in HCl than H2SO4. | N. laevis leaves extract | HCl and H2SO4 | Decrease | Increase | Gravimetric technique | Langmuir | Nnanna et al. 2012 |
Coconut coir dust extract reported as a good inhibitor for aluminum corrosion in 1 M HCl medium by the use of weight loss and hydrogen evolution method. It was exhibited that percentage IE efficiency increased with increasing temperature and concentration. Obtained results show the Langmuir adsorption performance | Coconut coir dust extract | 1 M HCl | Increase | Increase | Weight loss and hydrogen evolution | Langmuir | Umoren et al. 2012 |