Corrosion Inhibition of Copper Metal by Ethanolic Extract of Tinospora Cordifolia Plant in Sulfuric and Hydrochloric Acids of varying Strength (0.5 N to 3N) using Additives

Abstract

Using typical weight loss and thermometric techniques, the inhibitory impact of Tinospora cordifolia stem and leaf extract on copper corrosion in H2SO4 and HCl solutions of varying strength( 0.5N,1N,2N,3N) was investigated. The outcomes demonstrated that extracts worked as outstanding and effective inhibitors in acidic conditions, both in the absence and addition of additives. In an acidic environment, Tinospora cordifolia stem extract outperformed leaves extract in terms of inhibitory efficiency.The maximal inhibitory efficiency for stem extract at maximum inhibitor concentrations of 0.8% was 96.54% and 99.19% in 0.5 N H2SO4 and 95.26% & 97.78% in 0.5 N HCl, respectively, in the absence and presence of additives (KI & K2SO4). Similar to this, the effectiveness of the leaf extract\'s inhibition was 95.37% and 97.84% in 0.5 N H2SO4 and 94.15% and 96.92% in 0.5 N HCl, at a maximum inhibitor concentration of 0.8% in the absence and addition, respectively, of additives (KI & K2SO4). Based on the findings, stem extract suppresses H2SO4 and HCl more potently than leaf extract.Surface coverage (?) grows as inhibitor concentration rises (from 0.2% to 0.8%).The values of log(?/(1-?) increase linearly as inhibitor concentration rises,it has been demonstrated that ,the inhibitor\'s adsorption on the copper surface in the acid solutions followed Langmuir\'s adsorption isotherm. The current investigation discovered that the inhibitors (stem and leaf) were more effective at inhibiting the metal copper in H2SO4 and HCl acid solutions when an additive (KI and K2SO4) was present than when the inhibitors (stem and leaf) were present alone. Synergistic effects are to blame for this. The combined action of the two chemicals is more potent on a metal surface than the combined actions of the two chemicals acting separately or concurrently.

Introduction

I. INTRODUCTION

Corrosion is the deterioration of materials carried on by an environmental chemical or electrochemical assault. An environmental component is either consumed by or dissolved into a substance as a result of an inevitable interfacial contact between the substance and its surroundings. Copper is widely employed in huge equipment or machinery and many different sorts of industries because it has excellent scalability, thermal conductivity, noble metal characteristics, and electrical conductivity [1-3]. Manufacturing of wire, electrical, and electronic componentry is one instance [4]. Nevertheless, copper is often corroded during industrial production and rapidly combines with airborne oxygen to produce a variety of corrosion products, including some complex oxides. Pickling with sulphuric acid is a highly popular and successful procedure in industry to get rid of these corrosion by-products [5]. Inevitably, when cleaning, the acid solution will unavoidably harm the copper substrate in addition to eliminating all corrosion products. This will raise the likelihood of security events and result in significant financial losses [6, 7]. Including a proper corrosion inhibitor in the pickling solution is one of the most practical and efficient ways to stop copper substrate deterioration. As a result, numerous organic substances with heteroatoms (oxygen, sulfur, nitrogen, and phosphorus), conjugated double bonds, and polar functional groups have been considered corrosion inhibitors in recent years to prevent metal corrosion [8, 9]. The use of inhibitors is one of the most practical and economical options available for reducing corrosion of copper and its alloys. Organic substances with lone pair-donating heteroatoms (N, O, or S) or π-bonds typically have strong inhibitory effects [10-12]. Unfortunately, a lot of regularly used corrosion inhibitors are toxic for human beings and other creatures, hard to break down, and harmful to the environment. Current research efforts have been focused on finding new green corrosion inhibitors to replace the conventional ones in order to address these issues [13-16]. Therefore Tinospora Cordifolia plant has been selected for the study.

II. PLANT DESCRIPTION

A. Classification

Only the tropics of the Indian subcontinent are home to the Menispermaceae herbaceous vine known as Tinospora Cordifolia, often referred to as gurjo, heart-leaved moonseed, guduchi, or giloy [17]. It is a substantial deciduous climbing shrub that has several long, twining branches and a broad distribution. Long petioles are found along with simple, alternating exstipulate leaves. Guduchi, an Indian medicinal plant, has been used for many years in Ayurvedic formulas to treat a range of diseases. This plant has been used to cure a variety of ailments, including general weakness, impotence, gout, fever, diarrhea, dyspepsia, gonorrhea, skin disorders, viral hepatitis, anemia and secondary syphilis.  In compound formulations, guduchi is used medically to treat rheumatoid arthritis, diabetes, and jaundice. The root is considered to be a strong emetic and is used to alleviate intestinal obstruction [18-20]. Tinospora cordifolia's aerial parts, roots, and whole plant have produced a wide range of isolated compounds. Alkaloids (berberine, tinospporin, choline, isocolumbin, palmitine, tembetarine, etc.), steroids, diterpenoid lactones, and glycosides are some of the main components [21-22].

III. MATERIAL AND METHODS

A. Preparation of Stem and Leaves Extract

The Tinospora Cordifolia plant's newly harvested stem and leaves were air dried at room temperature before being processed into a powder. The dried stems and leaves of Tinospora Cordifolia are refluxed in a soxhlet unit with ethanol solvent and heated for the appropriate amount of time to get the stem and leaf extract.

B. Metal Used

For each experiment, copper coupons were utilized. Copper metal specimens were formulated by cutting a sheet of pure copper (99%) into squares coupons of  2.5 cm × 2.5 cm, each with a tiny hole at the top edge measuring about 2 mm in diameter. Each coupon was thoroughly cleaned and degreased before being polished to a high sheen.

C. Chemicals Used

Using analytical-grade reagent (98% H2SO4, 36% HCl), different concentration solutions of H2SO4 and HCl (i.e., 0.5N, 1N, 2N, and 3N) were produced in double distillation water and utilized for corrosion investigations. The ethanol solvent was used to make inhibitor solutions with various concentrations, including 0.2?, 0.4?, 0.6? and 0.8?.

D. Methods

1)  Weight Loss Method

Each specimen was put into a beaker with 50 mL of the test solution and suspended by a V-shaped glass hook constructed of fine capillaries while at room temperature. After the proper exposure, test specimens were washed with running water and dried with a hot air dryer. Double trials were conducted in each instance, and the average amount of weight loss or reduction was calculated. Using this equation, the percentage inhibition efficiency was estimated [23–25].

The current investigation discovered that the inhibitors (stem and leaf) were more effective at inhibiting the metal copper in H2SO4 acid HCl solutions when an additive (KI and K2SO4) was present than when the inhibitors (stem and leaf) were present alone. Synergistic effects are to blame for this. The combined action of the two chemicals is more potent on a metal surface than the combined actions of the two chemicals acting separately or concurrently. When organic inhibitors are used to prevent metallic corrosion, adsorption is a key factor. The effectiveness of inhibitors, measured as the percentage decrease in corrosion rate, can be qualitatively correlated to the amount of adsorbed inhibitors on the metal surface. It is believed that corrosion reactions are hindered from occurring at the active sites of the metal surface where adsorbed inhibitor species are present, whereas corrosion reactions are assumed to typically occur at the inhibitor-free regions of the surface. The percentage of the surface covered by adsorption inhibitors determines how effective the inhibition is, and vice versa.

V. ACKNOWLEDGEMENT

Vineeta Mandawara, one of the authors, expresses her deepest appreciation to the Synthetic and Surface Science Laboratory, Department of Chemistry, S.P.C. Govt. College, Ajmer, for providing the department with research facilities.

Conclusion

Tinospora Cordifolia stem and leaf extract has been shown to be an efficient corrosion inhibitor on copper in both the absence and presence of additives (KI & K2SO4) at varied concentrations of sulphuric (H2SO4) and hydrochloric acids (HCl) copper. The inhibitory efficacy of stem and leaf inhibitors rose with rising inhibitor concentrations from 0.2% to 0.8% as well as with decreasing strength of both acids, as shown by both weight loss and thermometric techniques. Maximum inhibitory effectiveness may be found at both the highest inhibitor concentration and the lowest acid concentration (0.5 N). According to the findings of the present study, stem extract is superior than leaf extract in preventing corrosion in H2SO4 and HCl acids. The results of thermometric analysis and weight reduction techniques show a strong correlation. Alkaloids, flavonoids, steroids, and tannins, which include more electronegative atoms like O, N, and S with lone pair electrons, as well as ?-electron conjugated aromatic rings, are examples of heterocyclic molecules found in the inhibitors, which are responsible for the adsorption process. These atoms combine with the metals vacant d-orbitals to form a coordination link that stops metal ions from dissolving in acidic situations. As a result, metal corrosion is prevented by the presence of inhibitors.

References

[1] C. Jing et al., Corros. Sci., Vol. 138, Pages 353-371, 2018. https://doi.org/10.1016/j.corsci.2018.04.027 [2] Y. Qiang et al., Three indazole derivatives as corrosion inhibitors of copper in a neutral chloride solution, Corros. Sci., 2017. [3] D. Wang et al., Corrosion control of copper in 3.5wt.% NaCl solution by domperidone: experimental and theoretical study, Corros. Sci., 2014. [4] H. Tian et al., Triazolyl-acylhydrazone derivatives as novel inhibitors for copper corrosion in chloride solutions, Corros. Sci. 2015. [5] B. Tan et al., Experimental and theoretical studies on inhibition performance of Cu corrosion in 0.5 M H2SO4 by three disulfide derivatives, J. Ind. Eng. Chem., 2019. [6] S. Mo et al., Study on the influences of two thiazole flavor ingredients on Cu corrosion caused by chloride ion, J. Colloid Interf. Sci., 2017. [7] B. Tan et al., Insight into the corrosion inhibition of copper in sulfuric acid via two environmentally friendly food spices: combining experimental and theoretical methods, J. Mol. Liq. 2019. [8] C. Verma et al., A thermodynamical, electrochemical, theoretical and surface investigation of diheteroaryl thioethers as effective corrosion inhibitors for mild steel in 1 M HCl, J. Taiwan Inst. Chem. E., 2016. [9] D.A. Winkler et al., Using high throughput experimental data and in silico models to discover alternatives to toxic chromate corrosion inhibitors, Corros. Sci., 2016 [10] A.M. Al-Sabagh et al. Structure effect of some amine derivatives on corrosion inhibition efficiency for carbon steel in acidic media using electrochemical and quantum theory methods, Egypt. J. Pet., 2013 [11] S. M. Abd El Haleem et al., Factors affecting the corrosion behaviour of aluminium in acid solutions. I. Nitrogen and/or sulphur-containing organic compounds as corrosion inhibitors for Al in HCl solutions, Corros. Sci., 2013 [12] C.M. Goulart et al., Experimental and theoretical evaluation of semicarbazones and thiosemicarbazones as organic corrosion inhibitors, Corros. Sci., 2013 [13] Tinospora.Drugs.com. 15 July 2019. Retrieved 5 September 2019. [14] Chopra R. N. Chopra\'s Indigenous Drugs of India. 2nd ed. Calcutta, India : Academic Publishers, 426-428, 1982. [15] Chintalwar G, Jain A, Sipahimalani A, et al. An immunologically active arabinogalactan from Tinospora Cordifolia. Phytochemistry, 52(6), 1089-1093, 1999. [16] Gupta S.S., Verma S.C., Garg V.P., Rai M. Anti-diabetic effects of Tinospora Cordifolia. Effect on fasting blood sugar level, glucose tolerance and adrenaline induced hyperglycaemia. Indian J Med Res. 55(7), 733-745, 1967. [17] Chintalwar G, Jain A, Sipahimalani A, et al. An immunologically active arabinogalactan from Tinospora Cordifolia. Phytochemistry, 52(6), 1089-1093, 1999. [18] Gupta S.S., Verma S.C., Garg V.P., Rai M. Anti-diabetic effects of Tinospora Cordifolia. Effect on fasting blood sugar level, glucose tolerance and adrenaline induced hyperglycaemia. Indian J Med Res., 55(7), 733-745, 1967. [19] Panchabhai TS, Kulkarni UP, Rege NN. Validation of therapeutic claims of Tinospora Cordifolia: a review. Phytother Res., 2(4), 425-441, 2008. [20] Upadhyay A.K., Kumar K., Kumar A., Mishra H.S. Tinospora Cordifolia (Willd.) Hook. F. and Thoms. (Guduchi) - Validation of the Ayurvedic pharmacology through experimental and clinical studies. Int J Ayurveda Res., 1(2), 112-121, 2010. [21] Roja G., Bhangale A.S., Juvekar A.R., Eapen S., D\'Souza S.F.. Enhanced production of the polysaccharide arabinogalactan using immobilized cultures of Tinospora Cordifolia by elicitation and in situ adsorption. Biotechnol Prog., 21(6), 1688-1691, 2005. [22] Sarma D., et al. Constituents of Tinospora Cordifolia root. Fitoterapia, 69, 541-542, 1998. [23] Kumpawat N., Chaturvedi A. and Upadhyay R.K., Iranian Journal of Materials Science and Engineering, 10, 4, 2013. [24] O.P. Meena, A. Chaturvedi, Elixir Corrosion & Dye, 116, 49989-49993, 2018. [25] Tripathi R., Chaturvedi A. and Upadhyay R.K., Journal of Electrochem. Soc. India, 60(1/2), 73, 2011. [26] Sethi T. Chaturvedi A., Upadhyay R. K. and Mathur S.P. Publish. Chem., 82, 591, 2008. [27] Jeengar N., Chaturvedi A. and Upadhyay R. K., International Journal of recent scientific research, 4, 1562-1566, 2013. [28] Talati J. D. and Gandhi D. K., Journal of Electrochem. Soc., 42(4), 239, 1993. [29] O. P. Meena and A. Chaturvedi, IJGHC, 8, 221 2019. [30] R. Sharma and A. Chaturvedi, E.I.J., 113, 49203-49208, 2017. [31] O. P. Meena and A. Chaturvedi, IOSR-JAC, 13(7), 22-32, 2020. [32] R. Sharma and A. Chaturvedi, IOSR Journal of Pharmacy, 7(8), 30-37, 2017. [33] A. Kadhim, et.al., Int. J. Corros. Scale Inhib. 10, 54, 2021. https://dx.doi.org/10.17675/ [34] A.Sehmi, et.al., J. Electrochem. Soc. 167, 155508, 2020. https://doi.org/10.1149/1945-7111/ [35] V. Mandawara, A. Chaturvedi, J. Sci. Res. 15(2), 519, 2023. http://dx.doi.org/10.3329/jsr.v15i2.61760 [36] A.M. Abdel-Gaber, et.al., Int. J. Ind. Chem. 11, 123, 2020. https://doi.org/10.1007/s40090 [37] R.S. Al-Moghrabi, et.al., Prot. Met. Phys. Chem. Surf. 55, 603, 2019. https://doi.org/10.1134/ [38] Nasreen Al Otaibi, et.al., Molecules 26(22), 7024, 2021. https://doi.org/10.3390/molecules [39] V. Mandawara & A. Chaturvedi, IOSR-JAC 16(3), 51, 2023. doi:10.9790/5736-1603015164

Copyright

Copyright © 2023 Vineeta Mandawara, Dr. Alok Chaturvedi. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.