International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020

ASSESSMENT OF THE PROTECTIVE PROPERTIES OF EXTRACT ON MILD STEEL IN SALINE SOLUTION

Einas Bin Sultan1, khawla Areef1,Manar Abazeid1, Muftah Shushni1 ,Elarbi Khalil2, Fathi M Sherif3

Email:[email protected] 1Department ofPharmacognosy,Faculty of Pharmacy, University of Tripoli, Tripoli, Libya. 2Department of Materials and Metallurgical Engineering,Faculty of Engineering, University of Tripoli, Tripoli, Libya. 3Department of Pharmacology, faculty of Pharmacy, University of Tripoli, Tripoli, Libya

ABSTRACT:

Several plant extracts have recently been reported as inhibitors for metallic materials in corrosive media. Thus, the corrosion inhibition of mild steel in a 3.5% NaCl solution in the presence of different concentrations of Acokanthera oblongifolia extract at a temperature range of 30 to 60 ⁰Cand for various immersion time was studied using weight loss method. The results showed that Acokanthera oblongifolia plant extract exhibit good corrosion inhibition efficiency. The inhibition efficiency of Acokanthera oblongifoliaextract increases with an increase in inhibitors concentration and through immersion periods but decreases with an increase in the temperature. The inhibitory effect could be due to the presence of some phytochemical compounds in the plantwhich is adsorbed on the surface of the mild steel.

KEYWORDS: Mild steel, Acokanthera oblongifolia extract, weight loss, corrosion inhibition, adsorption.

1. INTRODUCTION

Much research in recent years has been interested in studying the effect of natural plant-sourced products on metals corrosion as green inhibitors, and have confirmed that they have good corrosion inhibition efficacy[1 to 29].This interest in this aspect of the research was the result of the desire to obtain inhibitors that are environmentally friendly, non-toxic and available in large quantities also to avoid the highly toxic effect of some synthetic inhibitors on both environment and human beings. The inhibition effect of the natural products has been confirmed by several authors in acidic and nearly neutral media. R.A.-M.Saedah [1] found that the Juniperus plant can act as an inhibitor in the acid environment. J.K. Odusote, et al. [2] reported that Jatropha curcas exhibits good inhibitive efficacy in acidic media. M.S. Al-Otaibi, et al. [3] found that Teucrium oliverianum, Lycium shawii, Anville garcinii, Ochradenus baccatus, Cassia italica, Carthamus tinctorius,Artemisia sieberi, and Tripleurospermum auriculatum inhibited the corrosion of mild steel in acidic media. Z.V.P. Murthy, et al. [4] study showed that Hibiscus sabdariffa has an inhibiting property for mild steel corrosion in 1.2N H2SO4 than 1.2N HCl. Many other were studied on their inhibition efficiency in acidic media such as Theobroma cacao peel [5], Ginkgo leaf [6], Wrightia tinctoria, Clerodendrum phlomidis, and Ipomoea triloba [7], kola and tobacco

17

International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020 plants [8], Phyllanthus fraternus [9], Chlomolaena odorata L. [10], Roasted coffee extract [11], Piper guinensis [12], Spirulina platensis [13], Eriobotrya japonica Lindl. [14], Andrographis paniculata, Strychnos nux vomica, Moringa oleifera and Bacopa monnieri[15], Eucalyptus and Lippia Alba [16], Lantana camara L. [17].

Other research works concerned with the study of inhibition of mild steel corrosion in nearly neutral media such as the good inhibition effect exhibited by Capsaicin extract in sodium chloride aqueous solution [18], E.Akbarzadeh, et al.[19]reported that Kraft and Soda lignins extracted from oil palm empty fruit bunch can perform as good inhibitors. H.Challouf, et al. [20] found that Origanum majorana can be used as an inhibitor for mild steel corrosion in neutral 0.5M chloride medium. T.J. Tuaweri, et al. [21] observed that Neem leave extract potentially inhibits mild steel corrosion.R. I. Pramana, et al. [22]found that Pluchea indica Less. can act as a corrosion inhibitor. D.E. Abd-El-Khalek, et al. [23] found Nicotiana Leaves to be more effective in controlling the corrosion of steel in acidic solution than in neutral one. Other plants such as Myrmecodia pendans [24], Phyllanthus muellerianus [25], Vernonia amygdalina [26], Nerium oleander [27] propolis [28], Cascabela Thevetia [29] were exhibited good corrosion inhibition.

All of the previously mentioned research shows the successful use of plants as environmentally friendly green inhibitors. In our research, we try to find other plants that have this effect as green inhibitor. This study was on the Acokanthera oblongifolia. Acokanthera oblongifolia also is known as wintersweet, an evergreen plant belonging to the family [30].The Acokanthera oblongifolia highly toxic plant that contains Cardiac glycosides leads to Heart failure but at the same time is considered a medicinal plant that is used as emetics for snakebite [31], Appling topically to relieve itching [32].It has a cytotoxic effect[33], also exhibit antimicrobial activities against Pseudomonas aeruginosa , Shigella sonnei , Shigella flexneri , Bacillus cereus, Streptococcus pyogenes , and Bacillus subtilis [34] and antiviral activities against avian influenza virus type A (AI-H5N1) and Newcastle disease virus (NDV) [35]. The aim of this study is the detection of the major phytochemical groups of Cynodon dactylon plant extract and the determination of its corrosion inhibition efficiency on the protection of mild steel.

2. MATERIALS AND METHODS

2.1 TEST SOLUTION

NaCl& distilled water were used to prepare the aggressive solution (3.5%NaCl) for all experiments in the absence and presence of different concentrations of plant extract [1].

2.2 PLANTS PROCESSING

Acokanthera oblongifolia leaves was collected by hand randomly from the northwestern part of Libya (mashruealhadbaand farm of Faculty of Agriculture-University of Tripoli) between 23 September and 27 October 2018.The plants' specimen was taxonomically identified at botany department-faculty of science-university of Tripoli, Tripoli, Libya. Plant collected was rinsed under running water to remove any dust or dirt, then dried in shade & at room temperature until dried out completely, after that it was milled by an electric mill.

18

International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020

2.3 PLANT EXTRACTION

The powdered plant was refluxed in 80% ethanol using the reflux apparatus for 3 hours, the ethanolic extract was filtered using filter paper and the resulted filtrate was concentrated using a rotary evaporator finally dried in the oven at 60⁰C for 24 hours and stored in small jars at 2⁰C until use. At the time of an experiment, plant extract’s test solutions were prepared from stock extract at concentrations of 800, 400, 200, 100ppm using 3.5% NaCl solution [6].

2.4 PHYTOCHEMICAL SCREENING

Acokanthera oblongifolia leaves extract was subjected to Dragendorff’s , Mayer’s, Wagner’s tests to detect the presence of Alkaloids , Shinoda, Alkaline reagent test to detect flavonoids ,Keller- Killiani test for glycosides ,Ferric chloride test for phenolic compounds and tannins, Ninhydrin , Millon’s test for amino acids, Biuret test for proteins, Libermann Burchard, Salkowski’s test to detect sterols and triterpenoids, Fehling’s, Molisch , Benedict's to detect carbohydrates , Froth test for saponins, test for oils and fats, tests for organic acids and inorganic acids.[36,37].

3. STEEL SPECIMEN

The metal used for this study was mild steel, it was a rod with an average length of 4.0 cm and a diameter of 1.1 cm for weight loss method.The specimen surface was ground with emery paper (down to 600), washed with distilled water, degreased with acetone and dried with a stream of air.The sample was analyzed using FONDARY MASTER PRO instrument (optical emission spectrometer) at the high vocational center of casting (Al – Sayeh, Tripoli – Libya), The results of the analysis describe the chemical composition of the steel as follow (wt%):

Element C Si Mn S P Cr Fe Wt% 0.178 0.303 0.546 0.0127 0.0086 0.0127 Balance

4. CORROSION RATE MEASUREMENT

4.1 WEIGHT LOSS (GRAVIMETRIC) METHOD After thelength, diameter and weight measurement of the mild steel specimens by usingvernier caliper and analytical balance respectively, The specimens were completely immersed in 50ml of the test solution of 3.5% NaCl in the presence and absence of different concentrations of the inhibitor at different temperature (30,50,60 ⁰C). The specimens were removed from the test solutions after 4, 24, 48, 72hour, washed immediately with distilled water, degreased with acetone and dried with a stream of air then re- weighed again. Theweight loss data was obtained from the difference in weight of the specimens before and after the experiment. The corrosion rate (CR) was calculated from

퐖퐋 퐂퐑 = 퐀퐭

19

International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020

Where WL is weight loss in gram, A is the specimen surface area in cm2 and t which is the immersion period in hours. The inhibition efficiencies (%I) for the corrosion of mild steel in 3.5% NaCl containing a different concentration of inhibitor were calculated using:

퐂퐑퐛퐥퐚퐧퐤 − 퐂퐑퐢퐧퐡 %퐈 = ( ) 퐱ퟏퟎퟎ 퐂퐑퐛퐥퐚퐧퐤

Where CRblankand CRinhare the corrosion rate in the absence and presence of the inhibitor, respectively.

5. RESULTS AND DISCUSSION

5.1 PHYTOCHEMICAL SCREENING

The phytochemical screening confirms that Acokanthera oblongifolia extract contains alkaloids, flavonoids, glycosides, phenolic compounds, tannins, amino acids, proteins, sterols, triterpenoids, carbohydrates, , and organic acids.

5.2 INHIBITION EFFICIENCY

The results show that the inhibition efficiency of Acokanthera oblongifolia plant extract was 88.65%. That means our plants extract can acts as a good corrosion inhibitor in 3.5% NaCl media. That is due to the adsorption of some phytochemical compounds of the plant extract on the surface of the mild steel, more specifically the hetero atoms present in the phytochemical compounds will bind to the iron and change the charge density of mild steel resulting in retardation of cathodic and anodic reaction.The inhibition efficiency of Acokanthera oblongifolia plant extract increases with the increase of its concentration and immersion time as shown in Fig.1.

100 100 ppm 50

200 ppm Inhibition Inhibition efficacy/(%) 0 400 ppm 4 24 48 72 800 ppm Time/(hour)

Fig. 1 Effect of inhibitor concentration on protection efficiency on mild steel.

20

International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020

The effect of temperature on the inhibition efficiency is presented in Fig.2. The results show that the inhibition efficiency of the Acokanthera oblongifolia plant extract decreases with the increase of temperature.

Fig. 2 Effect of temperature on the inhibition efficiency of Acokanthera oblongifolia extract.

5.3 CORROSION RATE

The effect of concentration and immersion time on the corrosion rate is presented in Fig.3. The results show that the corrosion rate decreases with the increase of inhibitor concentration and immersion time.

Fig. 3 Effect of immersion time on the corrosion rate of mild steel in the presence and absence of plant extract.

The effect of temperature on the corrosion rate is presented in Fig.4. The results show that the corrosion rate increases with the increase of temperature.

21

International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020

0.15 Blank 0.1 100 ppm 0.05 200 ppm Corrosion Corrosion rate/(mpy) 0 4 24 48 72 Time/(hour)

Fig. 4 Effect of temperature on the corrosion rate of mild steel in the presence and absence of plant extract.

6. CONCLUSION

This study has dealt with Acokanthera oblongifolia plant extract and based on the results the following conclusions have been drowned:

 The major phytochemical groups of Acokanthera oblongifolia plant extract have been identified but the corrosion test was carried out without group separation.  The protection efficiency of mild steel by Acokanthera oblongifolia plant extract has increased upon immersion time and inhibitor concentration but has decreased with the increase of temperature.  Acceptable corrosion rates of mild steel were recorded under the inhibition of Acokanthera oblongifolia plant extract

7. CONFLICT OF INTEREST

The author declare that no conflict of interest with regard to this work.

22

International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020

8. ACKNOWLEDGMENTS

The authors would like to thank Dr. Mohammad Elmakhlouf for his assistance in taxonomical identification of the plant specimen.

REFERENCES

[1] R.A.-M. Saedah, Inhibition of mild steel corrosion using Juniperus plants as green inhibitior, African J. Pure Appl. Chem. 8 (2014) 9–22. doi:10.5897/AJPAC2013.0497.

[2] J.K. Odusote, O.M. Ajayi, Corrosion Inhibition of Mild Steel in Acidic Medium by Jathropha Curcas Leaves Extract, J. Electrochem. Sci. Technol. 4 (2013) 81–87. doi:10.33961/jecst.2013.4.2.81.

[3] M.S. Al-Otaibi, A.M. Al-Mayouf, M. Khan, A.A. Mousa, S.A. Al-Mazroa, H.Z. Alkhathlan, Corrosion inhibitory action of some plant extracts on the corrosion of mild steel in acidic media, Arab. J. Chem. 7 (2014) 340–346. doi:10.1016/j.arabjc.2012.01.015.

[4] Z.V.P. Murthy, K. Vijayaragavan, Mild steel corrosion inhibition by acid extract of leaves of Hibiscus sabdariffa as a green corrosion inhibitor and sorption behavior, Green Chem. Lett. Rev. 7 (2014) 209–219. doi:10.1080/17518253.2014.924592.

[5] Y. Yetri, N. Jamarun, World ’ s largest Science , Technology & Medicine Open Access book publisher Theobroma cacao Peel Extract as the Eco-Friendly Theobroma cacao Peel Extract as the Eco-Friendly Corrosion Inhibitor for Mild Steel Corrosion Inhibitor for Mild Steel, (n.d.). doi:10.5772/intechopen.73263.

[6] Y. Qiang, S. Zhang, B. Tan, S. Chen, Evaluation of Ginkgo leaf extract as an eco-friendly corrosion inhibitor of X70 steel in HCl solution Evaluation of Ginkgo leaf extract as an eco-friendly corrosion inhibitor of X70 steel in HCl solution, Corros. Sci. 133 (2018) 6–16. doi:10.1016/j.corsci.2018.01.008.

[7] N.L. Patel, S. Jauhariand, G.N. Mehta, S.S. Al-Deyab, I. Warad, B. Hammouti, Mild steel corrosion inhibition by various plant extracts in 0.5 M sulphuric acid, Int. J. Electrochem. Sci. 8 (2013) 2635–2655.

[8] C.A. Loto, R.T. Loto, A.P.I. Popoola, Corrosion and plants extracts inhibition of mild steel in HCl, 6 (2011) 3616–3623. doi:10.5897/IJPS11.923.

[9] N.S. Patel, J. Hrdlicka, P. Beranek, M. Přibyl, D. Šnita, B. Hammouti, S.S. Al-Deyab, R. Salghi, Extract of Phyllanthus fraternus Leaves as Corrosion Inhibitor for Mild Steel in H 2 SO 4 Solutions, 2014. www.electrochemsci.org.

[10] I.B. Obot, E.E. Ebenso, Z.M. Gasem, S. Arabia, Eco-friendly Corrosion Inhibitors: Adsorption and Inhibitive Action of Ethanol Extracts of Chlomolaena Odorata L. for the Corrosion of Mild Steel in H 2 SO 4 Solutions, 2012. www.electrochemsci.org.

[11] E.C. do C.A. de Souza, B. de A. Ripper, D. Perrone, E. D’Elia, Roasted Coffee Extracts as Corrosion Inhibitors for Mild Steel in HCL Solution, Mater. Res. 19 (2016) 1276–1285. doi:10.1590/1980-5373-mr-2015-0740.

[12] E.E. Ebenso, A.O. Odiongenyi, Corrosion inhibitive properties and adsorption behaviour of ethanol extract of Piper guinensis as a green corrosion inhibitor for mild steel in H 2 SO 4, 2008. http://www.academicjournals.org/AJPAC.

[13] C. Kamal, M.G. Sethuraman, Spirulina platensis – A novel green inhibitor for acid corrosion of mild steel, Arab. J. Chem. 5 (2012) 155–161. doi:10.1016/j.arabjc.2010.08.006.

[14] X. Zheng, M. Gong, Q. Li, L. Guo, Corrosion inhibition of mild steel in sulfuric acid solution by loquat ( Eriobotrya japonica Lindl .) leaves extract, Sci. Rep. (2018) 1–15. doi:10.1038/s41598-018-27257-9.

[15] A. Singh, E.E. Ebenso, M.A. Quraishi, Corrosion Inhibition of Carbon Steel in HCl Solution by Some Plant Extracts, 2012 (2012). doi:10.1155/2012/897430.

[16] A.F. Gualdrón, E.N. Becerra, D.Y. Peña, J.C. Gutiérrez, H.Q. Becerra, Inhibitory effect of Eucalyptus and Lippia Alba essential oils on the corrosion of mild steel in hydrochloric acid, 4 (2013) 143–158.

23

International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020

[17] S. Kalpana, GREEN APPROACH TO CORROSION INHIBITION OF MILD STEEL IN 1 M HCl SOLUTION BY AQUEOUS EXTRACT OF LANTANA CAMARA L . LEAVES, 13 (2015) 1157–1162.

[18] C.G. Vaszilcsin, M.L. Dan, A.F. Enache, I. Hulka, Inhibiting Corrosion Process of Carbon Steel in Sodium Chloride Aqueous Solution by Capsaicin Extract, 61 (2016).

[19] E. Akbarzadeh, M.N.M. Ibrahim, A.A. Rahim, Corrosion Inhibition of Mild Steel in Near Neutral Solution by Kraft and Soda Lignins Extracted from Oil Palm Empty Fruit Bunch, 6 (2011) 5396–5416.

[20] H. Challouf, N. Souissi, M. Ben Messaouda, R. Abidi, A. Madani, Origanum majorana Extracts as Mild Steel Corrosion Green Inhibitors in Aqueous Chloride Medium, (2016) 532–544.

[21] T.J. Tuaweri, E.A. Ogbonnaya, O.O. Onyemaobi, CORROSION INHIBITION OF HEAT TREATED MILD STEEL WITH NEEM LEAVE EXTRACT IN A CHLORIDE MEDIUM, (2015) 404–409.

[22] J. Wahyuadi, A. Rustandi, Corrosion Inhibition of Low Carbon Steel by Pluchea Indica Less in 3 . 5 % NaCL Solution, (2013). doi:10.4028/www.scientific.net/AMR.785-786.20.

[23] A.M.A.-G. D.E. Abd-El-Khalek, B.A. Abd-El-Nabey, Evaluation of Nicotiana Leaves Extract as Corrosion Inhibitor for Steel in Acidic and Neutral Chloride Solutions, 30 (2012) 247–259. doi:10.4152/pea.201204247.

[24] A. Pradityana, A. Shahab, L. Noerochim, D. Susanti, Inhibition of Corrosion of Carbon Steel in 3 . 5 % NaCl Solution by Myrmecodia Pendans Extract, 2016 (2016).

[25] N. Concrete, Effects of Phyllanthus muellerianus Leaf-Extract on Steel-Reinforcement Corrosion in, (2016) 3–6. doi:10.3390/met6110255.

[26] C.A. Loto, O.O. Joseph, R.T. Loto, Inhibition Effect of Vernonia amygdalina Extract on the Corrosion of Mild Steel Reinforcement in Concrete in 3 . 5M NaCl Environment, 8 (2013).

[27] A.S. J, P.M. T, M. Arthanareeswari, P. Kamaraj, M.K. R, S.R. Patel, A. Selvi, Evaluation of Inhibitory Effect of Nerium oleander Leaf Extract on Mild Steel Corrosion in Aqueous Medium, 10 (2018) 1–6.

[28] V. Grudić, I. Bošković, S. Martinez, B. Knežević, Corrosion inhibition mild steel in NaCl solution in the presence of propolis extract, Maced. J. Chem. Chem. Eng. 37 (2018) 203–213. doi:10.20450/mjcce.2018.1513.

[29] F. AS, E. A, R. R, N. M, Cascabela Thevetia Plant Extract as Corrosion Inhibitor for Carbon Steel in Polluted Sodium Chloride Solution, J. Anal. Pharm. Res. 6 (2018) 1–10. doi:10.15406/japlr.2017.06.00168.

[30] B. Sennblad, B. Bremer, Classification of Apocynaceae s.l. According to a new approach combining Linnaean and phylogenetic , Syst. Biol. 51 (2002) 389–409. doi:10.1080/10635150290069869.

[31] E.E. Elgorashi, J.L.S. Taylor, A. Maes, J. Van Staden, N. De Kimpe, L. Verschaeve, Screening of medicinal plants used in South African traditional medicine for genotoxic effects, Toxicol. Lett. 143 (2003) 195–207. doi:10.1016/S0378- 4274(03)00176-0.

[32] U. Mabona, S.F. Van Vuuren, Southern African medicinal plants used to treat skin diseases, South African J. Bot. 87 (2013) 175–193. doi:10.1016/j.sajb.2013.04.002.

[33] R.A. Hassan, E.M. Hassan, N.A. Ibrahim, N.M. Nazif, Triterpenes and cytotoxic activity of Acokanthera oblongifolia Hochst. growing in Egypt, Res. J. Pharm. Biol. Chem. Sci. 6 (2015) 1677–1686.

[34] W. Otang-Mbeng, A.J. Afolayan, Antimicrobial and antioxidant efficacy of acokanthera oblongifolia hochst. (apocynaceae), Int. J. Pharmacol. 13 (2017) 1086–1091. doi:10.3923/ijp.2017.1086.1091.

[35] M.M.E.-S. Howaida I. Abd-Alla, Amal Z. Hassan, Maha Soltan, Atef G. Hanna, Cytotoxic , Antimicrobial and Antiviral Activities of Acovenoside A : A Cardenolide Isolated from an Egyptian Cultivar of Acokanthera spectabilis, 12 (2018) 2018.

[36] L. Osbeck, Phytochemical screening and evaluation of leaves of Citrus limon, (2018) 50–56.

[37] R. Varghese, PHYTOCHEMICAL SCREENING AND ANTIBACTERIAL ACTIVITY OF CYNODON DACTYLON AGAINST HUMAN PATHOGENS ., (2018). doi:10.21474/IJAR01/5513.

24

International Journal of Pharmacy Practice and Pharmaceutical Sciences , Vol. (2), Issue (1), 2020

25