Table 1 Plants as corrosion inhibitors against mild steel corrosion
Study Conducted | Plant product | Solution | Effect of temperature on percentage inhibition efficiency | Effect of concentration on percentage inhibition efficiency | Methods | Adsorption type and isotherm used | Reference |
|---|---|---|---|---|---|---|---|
Eichhornia crassipes is noted as one of the most important and noxious freshwater weed; the extracts of its leaves and roots were reported as good corrosion inhibitor for mild steel corrosion in HCl solutions using gasometric technique, and its modeled structures provides additional insight into the mechanism of inhibitory action by DFT | E. crassipes (leaf and root) | HCl | Decrease with rise in temperature | Increase | Gasometric technique | (Physically adsorbed) | Ulaeto et al. 2012 |
Nauclea latifolia commonly known as pin cushion tree is a straggling shrub or small spreading tree that belongs to the family Rubiaceae. The effects of ethanol (ENL), alkaloids (ANL), and non-alkaloids (NNL) extracts from the root of N. latifolia on the dissolution of carbon steel in H2SO4 solutions were shown their effective inhibition by followed trend ANL>ENL>NNL. Gasometric method was use to perform practical data and obtained results show that percentage inhibition efficiency increase with concentration but decrease with rise in temperature | N. latifolia (root) | H2SO4 | Decrease with rise in temperature | Increase | Gasometric technique | Temkin | Okafor et al. 2013 |
Banana peel extract (constituent of this extract is bananadine (3Z,7Z,10Z)-1-oxa-6-azacyclododeca-3,7,10-triene) was reported as a good corrosion inhibitor with Zn in distilled water for carbon steel corrosion by the weight loss, thermometric , FTIR, and AFM analysis. Obtained results show that percentage inhibition efficiency first decrease with the addition of Zn but after increasing Zn concentration it increased | Banana peel extract + Zn | Distilled water | – | First decrease with Zn after increase with increasing concentration of Zn inhibition efficiency increases | Weight loss, thermometric , FTIR, and AFM analysis | – | Sangeetha et al. 2012 |
By the use of quantum chemical calculations, the active compound were reported as follows: (Kalmegh) Andrographis paniculata— andrographolide, (Meethi Neem) Murraya koenigii— mahabinine and pyrayafoline, (Bael) Aegle marmelos—skimmianine, (Kuchla) Strychnos nuxvomica—brucine, (Shahjan) Moringa oleifera—arginine, (Orange) Citrus aurantium—threonine, and (Arjun) Terminalia arjuna—sitosterol, Due to these active molecules, they show their inhibition effect for corrosion | The extracts of (Kalmegh) Andrographis paniculata, (Meethi Neem) Murraya koenigii, (Bael) Aegle marmelos, (Kuchla) Strychnos nuxvomica, (Shahjan) Moringa oleifera, (Orange) Citrus aurantium, and (Arjun) Terminalia arjuna | HCl | – | – | DFT, molecule analysis, and quantum calculations | – | Singh et al. 2013 |
Aloe vera plant belongs to the family of Liliacea. The constituents of gel are polysaccharides, glycoproteins, vitamins, mineral, and enzymes. Obtained results show its synergistic type effect, and percentage inhibition efficiency was decrease with rise in temperature and increase with increasing extract concentration | Aloe vera | HNO3 | Decrease with rise in temperature | Increase | Gravimetric technique | Chemisorption | Gupta and Jain 2014 |
C. sinensis leaf extract reported as a corrosion inhibitor in aqueous medium by the use of weight loss, UV, and FT-IT methods. Obtained results show that inhibition efficiency increase with increasing inhibitor concentration but decrease with rise in temperature | C. sinensis leaf extract | Aqueose | Decrease with rise in temperature | Decrease | Weight loss method, pH, UV–vis, and FT-IR | Physical adsorption | Yamuna and Athony 2014 |
Hibiscus rosa-sinensis leaves extract reported as a good corrosion inhibitor for mild steel in HCl medium by the use of weight loss and EIS techniques. Obtained results show that the percentage inhibition efficiency was increased with the increasing temperature and concentration and show mixed-type inhibitor effect, and adsorption process was spontaneous and followed the Langmuir, Flory-Huggins and Freundlich adsorption isotherms | H. rosa-sinensis (Jasud) | HCl | Increase | Increase | Gravimetric (weight loss) and electrochemical techniques | Langmuir, Flory-Huggins and Freundlich adsorption | Desai 2015a |
Ilex paraguariensis extracts reported as a good corrosion inhibitor for carbon steel in HCl medium by the use of weight loss and EIS techniques. Its inhibition efficiency increased with the increase of concentration and time. Obtained results show that I. paraguariensis act as both type inhibitor and obeyed the Langmuir adsorption isotherm | I. paraguariensis | HCl | Increase | Increase | Weight loss and electrochemical measurements | Langmuir adsorption isotherm | Souza et al. 2015 |
Ruta graveolens extract reported as a good corrosion inhibitor for mild steel corrosion in HCl medium by PDP and weight loss method. Obtained results show that percentage inhibition efficiency increase with increasing concentration of inhibitor but decrease with rise in temperature and obeyed the Langmuir adsorption isotherm | R. graveolens extract | HCl | Decrease with rise in temperature | Increase | Potentiodynamic polarization and weight loss techniques | Langmuir adsorption isotherm | Majeed et al. 2014 |
Musa sapientum which is commonly called banana is a herbaceous plant, belonging to the family of Musaceae. It is reported as a good corrosion inhibitor for mild steel in H2SO4 medium with tetraoxosulphate (vi) acid by the use of E. chemical measurements. Obtained results show that corrosion rate decrease with increasing concentration rate of inhibitor but increase with rising temperature. Simply followed the physical adsorbtion | M. sapientum peels extract + concentrated tetraoxosulphate (vi) acid | H2SO4 | Decrease | Increase | Weight loss, E. chemical measurements | Physical adsorption | Salami et al. 2012 |
Extract of fenugreek leaves reported as a good inhibitor for mild steel in HCl and H2SO4 solution but more efficient in HCl solution. Inhibition efficiency was decrease with rise in temperature but increase with increasing inhibitor concentration in HCl while both temperature and concentration increased the inhibition efficiency for mild steel in H2SO4 solution. Langmuir adsorption isotherm followed in HCl medium and Temkin followed in H2SO4 medium | Extract of fenugreek leaves | HCl and H2SO4 | Decrease in HCl solution but increase In H2SO4 solution | Increase in both solutions | Gravimetric technique | Langmuir in HCl solution, Temkin in H2SO4 solution | Noor 2007 |
Cotula cinerea, Retama retam, Artemisia herba reported as good corrosion inhibitors for mild steel in H2SO4 medium by weight loss and EIS methods | Cotula cinerea, Retama retam, Artemisia herba | H2SO4 | – | – | Weight Loss and E. chemical measurements | – | Raja and Sethuraman 2008b |
Eclipta alba reported as an effective corrosion inhibitor for mild steel in H2SO4 medium by the use of weight loss and potentiodynamic polarization methods. Obtained results show that inhibitor behave as mixed-type inhibitor; inhibition efficiency increase with concentration value but decrease with rise in temperature. Obeyed the Langmuir adsorption isotherm | E. alba | H2SO4 | Decrease with rise in temperature | Increase | Weight loss, potentiodynamic polarization, and impedance methods | Langmuir adsorption | Shyamala and Arulanantham 2009 |
Terminalia catappa reported as a corrosion inhibitor in HCl medium by the use of weight loss and PDP methods. Obtained results show that inhibition efficiency increased with increasing concentration of inhibitor but decrease with rise in temperature and described as mixed-type inhibitor | T. catappa | HCl | Decrease | Increase | Weight loss, polarization, FTIR, and scanning electron microscope studies | Mixed-type inhibition | Vasudha and Saratha 2011 |
Theobroma cacao peel polar extract reported as a corrosion inhibitor for mild steel in HCl medium by the use of weight loss method, potentiodynamic polarization, and EIS techniques. Obtained results show that inhibition efficiency increased with the inhibitor concentration level but decreased with the rise in temperature and obeyed the Langmuir adsorption isotherm | T. cacao peel polar extract (TCPE) | HCl | Decrease | Increase | Weight loss method, potentiodynamic polarization, and EIS techniques | Langmuir adsorption isotherm | Yetri et al. 2014 |
It’s reported that the mature leaves of Combretum bracteosum extracts inhibited the corrosion of mild steel in H2SO4 medium by the use of gravimetric and hydrogen evolution methods. Obtained results show that the inhibition efficiency increases with the inhibitor concentration and decreases with temperature. Obtained result obeyed the Frumkin adsorption isotherm | C. bracteosum | H2SO4 | Decrease with rise in temperature | Increase | Gravimetric and hydrogen evolution | Frumkin adsorption isotherm | Okafor et al. 2009 |
Cyamopsis tetragonoloba reported as an effective corrosion inhibitor for mild steel in HCl medium by use of weight loss, PDP, and EIS techniques. Obtained results show that inhibition efficiency increase with increasing inhibitor concentration but decrease with rise in temperature. Obeyed the Temkin and Langmuir adsorption isotherms | C. tetragonoloba | HCl | Decrease with rise in temperature | Increase | Potentiodynamic polarization | Temkin and Langmuir | Subhashini et al. 2010 |