EFFECT OF INHIBITIVE INFLUENCE OF AQUEOUS EXTRACT OF FENUGREEK SPROUTS ON THE CORROSION OF ALUMINIUM IN 1N NAOH

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1 International Journal of Mechanical Engineering and Technology (IJMET) Volume 8, Issue 5, May 17, pp , Article ID: IJMET_8_5_69 Available online at ISSN Print: and ISSN Online: IAEME Publication Scopus Indexed EFFECT OF INHIBITIVE INFLUENCE OF AQUEOUS EXTRACT OF FENUGREEK SPROUTS ON THE CORROSION OF ALUMINIUM IN 1N NAOH Levin Daniel J V PG Student, Department of Civil Engineering, Karunya University, Coimbatore, India Daniel C Research Scholar, Department of Civil Engineering, Karunya University, Coimbatore, India Joel Shelton J Research Scholar, Department of Civil Engineering, Karunya University, Coimbatore, India Arun Raj E Assistant Professor, Department of Civil Engineering, Karunya University, Coimbatore, India Vincent Sam Jebadurai S Assistant Professor, Department of Civil Engineering, Karunya University, Coimbatore, India Hemalatha G Associate Professor, Department of Civil Engineering, Karunya University, Coimbatore,India ABSTRACT Aluminium and aluminium alloys are of economic importance because of their characteristics low cost and light weight. It is used in manufacturing aero plane parts, surgical instruments, and household utensils and in the construction of buildings. Thus aluminium plays an important role in industries. One such disadvantage is aluminium corrodes in alkaline medium. The open circuit potential is more positive than that of a resistive oxide film at the Al surface. Further, a significant amount of Al is dissolved into the solution with evolution of hydrogen. Therefore the inhibition of corrosion of aluminium has become much significant. The influence of natural extract of fenugreek sprouts on the corrosion of aluminium in 1N NaOH has been studied by weight loss, polarization, EIS measurement and antimicrobial studies. Key words: Corrosion, Inhibitor, Aluminium, Tafel plot editor@iaeme.com

2 Levin Daniel J V, Daniel C, Joel Shelton J, Arun Raj E, Vincent Sam Jebadurai S, Hemalatha G Cite this Article: Levin Daniel J V, Daniel C, Joel Shelton J, Arun Raj E, Vincent Sam Jebadurai S and Hemalatha G, Effect of Inhibitive Influence of Aqueous Extract of Fenugreek Sprouts on the Corrosion of Aluminium in 1N NaOH. International Journal of Mechanical Engineering and Technology, 8(5), 17, pp INTRODUCTION Corrosion is the disintegration of an engineered material into its constituent atoms due to chemical reactions with its surroundings. In the most common use of the word, this means electrochemical oxidation of metals in reaction with an oxidant such as oxygen [1]. Formation of an oxide of iron due to oxidation of the iron atoms in solid solution is a wellknown example of electrochemical corrosion, commonly known as rusting. This type of damage typically produces oxide(s) or salt(s) of the original metal. Corrosion can also occur in materials other than metals, such as ceramics or polymers, although in this context, the term degradation is more common. Many structural alloys corrode merely from exposure to moisture in the air, but the process can be strongly affected by exposure to certain substances (see below) []. Corrosion can be concentrated locally to form a pit or crack, or it can extend across a wide area more or less uniformly corroding the surface. Because corrosion is a diffusion controlled process, it occurs on exposed surfaces [4-6].. PREPARATIONS OF FENUGREEK SPROUTS EXTRACTS Stock solution of the inhibitor extract were prepared by boiling 1 g of dried, grounded fenugreek sprouts in 5 ml of de-ionized water for 1 h. Both the freshly prepared extract and that aged in a refrigerator for two months give almost the same results [18]. 3. RECORDING SPECTRA Figure 1 Fenugreek Sprouts 3.1. FT-IR spectrum The sample is pelletized with KBr pellets and the spectrum was recorded using perkinelmer instrument 3.. OCP Measurement The steady value of open circuit potential of aluminium electrode, immersed in the test solutions, was measured without passing current after it is kept in the solution for about 45 minutes, using saturated calomel electrode as a reference electrode editor@iaeme.com

3 Effect of Inhibitive Influence of Aqueous Extract of Fenugreek Sprouts on the Corrosion of Aluminium in 1N NaOH 3.3. Electrochemical Impedance Spectroscopy Impedance measurements were carried out using Princeton electrochemical analyzer using three electrodes. The distance between the reference electrode and working electrode was kept with in a known distance (1mm). The working electrode was separated from the countered electrode using low porestic sintered glass disk. The temperature was noted. Impedance measurements were made at the open circuit potential (OCP) is a known frequency range (1 khz-5 khz) at known intervals time (3 sec) till the value of polarization resistance, Rp, remain study Antibacterial Susceptibility Test Antibacterial susceptibility test is done in order to find out the effectiveness of our sample. As most of the pathogen develops drug resistance, we need to find an effective drug. The medium and the required glass wares were sterilized using the autoclave at 11 degree for 15 minutes. After sterilization, media and the glass wares were kept in the lamina air allow chamber. About 1.54 ml of the medium was poured on a petriplate under sterilized condition using the pour plate technique. The medium was allowed to solidify. About.1 ml of the desired sample was spread on the petriplate with the medium by spread plate technique using the sterile L rod. After the spread plate method the wells were punctured in the medium using the gel puncture. About ml of the culture and the control sample were placed on the well. The plates were kept for incubation for 4 hours. The results were observed after 4 hours. 4. RESULTS AND DISCUSSION 4.1. Structure Identification-Inhibitor Table 1 show the IR spectrum of aqueous extract of fenugreek sprouts was recorded in the region of 4-4cm. Table 1 IR Spectrum Peak, cm Vibration mode N-H stretching Mode C-N stretching Mode C=O stretching Mode N-H wagging 4.. Weight Loss Method The wasteful corrosion reactions have to be stopped to a considerable extent by the use of inhibitors.. It reduces considerably by the addition of the various concentration of aqueous extract of fenugreek sprouts as shown in table 1.The maximum percentage was found to be 7.33(table 1). When aluminum corrodes in NaOH solution, the evolution of hydrogen over voltage on aluminum, the gassing is however reduced considerably by the addition of aqueous extract of fenugreek sprouts Langmuir Adsorption In a certain range of inhibitor and temperature where monolayer adsorption is readily maintained over the aluminum surface [19], the Langmuir adsorption may be expressed as follows, θ/ (1-θ) = AC exp (-Q/RT) 64 editor@iaeme.com

4 Levin Daniel J V, Daniel C, Joel Shelton J, Arun Raj E, Vincent Sam Jebadurai S, Hemalatha G Where, A is a constant dependent on characteristic of the system of adsorption, C is a concentration of the inhibitor, Q is the heat capacity of adsorption, B is the occupied area and (1-θ) is the vacant site not occupied by the inhibitor. The degree of coverage θ is given below. θ = 1-(Iinh/Iuninh) Where Iinh and Iuninh are the corrosion rates in solution with and without inhibitor, respectively. The above equation can be represented in the following form log (θ/ (1-θ)) = log A + log(c-q)/.33rt 4.4. Open Circuit Potential Rate of corrosion of aluminum, in the alkaline solution greatly increases with product. The OH- ions are specifically adsorbed at the point of interaction leading to the development of large negative potential on the metal surface. Therefore, aluminum dissolves in alkaline medium. Al Al3+ +e- The difference in corrosion rate arises due to the reason that Al3+ is readily complexed. The Al3+ readily forms complexes with OH- ions then rapidly dehydrates to form AlO- Al3+ +4OH- Al(OH)4 Al(OH)4 AlO +HO The reaction proceeds rapidly at room temperature. The reaction, at cathodic site is given below. HO + e- OH- + H+ H+ H Due to the above vigorous reaction of Al3+ with OH- the concentration of Al3+ is so reduced that the potential of Al-Al3+ electrode is decreased much below that of H+- H(g)electrode. A highly negative potential for Al-Al3+ electrode. When aluminium dissolves anodically both Al3+ and Al+ are formed initially. The univalent ion then reduces HO to form the trivalent ion inn accord with the equation. Al AI+ + e- Al+ + HO Al3+ +H+OH- The net reaction is Al Al3+ + 3e- E=.7V 4.5. Polarization Studies The anodic and cathodic polarization curves of aluminium [] in 1.N NaOH were recorded in the absence and in the presence of inhibitor. Thus, the inhibitor, present in high concentrated, act as polarizer of the cathode and inhibit the corrosion of aluminium. The inhibitive influence of the inhibitor is considerable for considerable increase in concentration of the inhibitor. The maximum percentage inhibition efficiency was found to be In the inhibition efficiency values determined by weight loss method and polarization techniques are showed close agreement is shown table 3. The corrosion parameters such as OCP, Icorr.,Ecorr., were determined from graph(fig, 3&4) galvanostatic polarization studies. It was observed that anodic was greater than cathodic polarization in all solution. It is thus clear that the corrosion is predominantly under anodic control in the presence and the absence of the inhibitor. The inhibitor is of mixed type because editor@iaeme.com

5 Effect of Inhibitive Influence of Aqueous Extract of Fenugreek Sprouts on the Corrosion of Aluminium in 1N NaOH the slopes of both anodic and cathodic polarization curve changes with the change in concentration of inhibitor Electrochemical Impedance Spectroscopy The presence study the electrochemical impedance spectra resolution of commercial aluminium in 1N NaOH in the absence and presence of inhibitor were recorded at the OCP an A.C impedance of amplitude of 1mV was applied. Real parts of the impedance were plotted against the corresponding imaginary parts to get Nyquist plots which have semicircle, at high frequency and loop at intermediate frequency in the absence and presence of inhibitor fig(6,7&8) Nyquist plot,i.e.,(-z" Vs Z ) gives a direct read to both Rs and Rct. Where Rs is ohmic resistance of the solution and Rct is charge transfer resistance corresponding to the charge transfer process. The sum of the values of charge transfer resistance and the solution resistance.(rct,rs), corresponds to the points at which semicircle plots cuts Z axis in the high frequency region. ω=πf(z max)=1/cdl.rt Where F is the frequency in Hertz(Hz). The inductive loop appearing in the intermediate frequency region, is probably due to multi-step this solution of aluminium. The following is the equivalent electrical circuit. It can be seen that impedance diagram in most of the cases are not perfect semicircles. This different has been attributed to frequency depression[3&4]. But they are almost semicircles, which indicate that the corrosion of aluminum in sodium hydroxide is mainly controlled by a charge transfer process. (Table 5)gives values of Rt,,,Cdl and I.E obtained from impedance diagrams. It can be seen from this table the inhibitor fenugreek leaves enhances Rt decreases Cdl values and increases values of inhibition efficiency Antibacterial Activity The Table 6 shows that the inhibitor aqueous extract of fenugreek sproutes used in various microorganisms. The inhibitors are more active in staplococcus microorganism in table. Table Effect of aqueous extract of fenugreek sprouts on the rate of corrosion of aluminium in 1N NaOH at 3±1ºc. [Inhibitor] Rate of Corrosion Percentage Inhibition ml X 1-4, g cm h Blank editor@iaeme.com

6 Levin Daniel J V, Daniel C, Joel Shelton J, Arun Raj E, Vincent Sam Jebadurai S, Hemalatha G Table 3 Anodic and cathodic polarization of aluminium in 1N NaOH without and with aqueous extract of fenugreek sprouts. [inhibitor]ml OCPV EcorrV Icorr m cm Percentage Inhibition Blank Table 4 Comparison of inhibition efficiency measured by weight loss and polarization method of aqueous extract of fenugreek sprouts [inhibitor] ml Weight loss studies Inhibition efficiency Polarization studies Table 5 Langmuir adsorption isotherm for the inhibition of corrosion of aluminium in 1N NaOH by aqueous extract of fenugreek sprouts. [Inhibitor] ml Icorr macm θ=(iunin-iin)/iunhi log θ/(1-θ) +logθ/(1-ɵ) 4+logC Blank Table 6 Impedance parameter for aluminium in 1N NaOH without and with aqueous extract of fenugreek sprouts. [inhibitor]ml RtOhm CdlF Inhibition efficiency Blank Table 7 Antibacterial activity of various microorganisms. S.No Name of the organism Zone of inhibition in mm 1. Klebsiellasps. 7. Bacillus sps E.coli 1 4. Staphylococcus sps editor@iaeme.com

7 Effect of Inhibitive Influence of Aqueous Extract of Fenugreek Sprouts on the Corrosion of Aluminium in 1N NaOH E w e / V v s. S C E log I/m A 1 Figure Anodic and cathodic polarization of aluminium in 1N NaOH 1 ml E w e / V v s. S C E log I/m A 1 Figure 3 Anodic and cathodic polarization of aluminium in 1N NaOH- Impedance I m ( Z ) / O h m Re ( Z)/Ohm 1 Figure 4 Electrochemical impedance spectrum for aluminium in 1N NaOH - 1 ml editor@iaeme.com

8 Levin Daniel J V, Daniel C, Joel Shelton J, Arun Raj E, Vincent Sam Jebadurai S, Hemalatha G.5 - I m ( Z ) / O h m Re (Z )/Oh m 6 8 Figure 5 Electrochemical impedance spectrum for aluminium in 1N NaOH - 5 ml I m ( Z ) / O h m Re ( Z)/Ohm 8 1 Figure 6 Electrochemical impedance spectrum for aluminium in 1N NaOH - 1 ml I m ( Z ) / O h m.5.5 Re (Z)/Ohm 4 6 Figure 7 Electrochemical impedance spectrum for aluminium in 1N NaOH editor@iaeme.com

9 Effect of Inhibitive Influence of Aqueous Extract of Fenugreek Sprouts on the Corrosion of Aluminium in 1N NaOH 1. Spectrum Name: SP-Ext.sp FTIR SPECTRUM Date: 3/3/ %T cm SP-Ext.pk SP-Ext.sp %T 1. REF Figure 8 FT-IR Spectrum of fenugreek sprouts extract 5. CONCLUSION In this present studies the formation of products and structure are confirmed by FT-IR spectral studies. The inhibitive influence of the inhibitor Fenugreek sprouts extract on the corrosion of aluminum in 1. N NaoH was studied by weight loss method, polarization measurements, E.I.S and antibacterial studies. The corrosion decreased with increasing addition of Fenugreek sprouts extract one due to progressive adsorption of the inhibitor on the aluminium metal surface. The open circuit potential of aluminum in 1. N NaOH in the presence of the inhibitors of varying concentration did not show any significance shift in its values. The maximum inhibition efficiency values 71.3 obtained by the E.I.S method. The antibacterial activity of fenugreek sprouts extract in staphylococcus microorganism is the maximum percentage inhibition efficiency. REFERENCES [1] L.I. Antropov, 1st Int. Congr. Metal Corros., London, Butterworth, London (1961), 148. [] A.R. Despic, Ind. J. Tech. 4, 465 (1986). [3] Paramasivam, S. VenkatakrishnanIyer and V. Kapali, Brit. Corr. J. 7 (1994). [4] J.F. Coper, in: Aluminium - Air Battery Development towards an Electric Car, Energy and Technology Review, Lawrence Livermore National Laboratory, 1983, p. 46. [5] N.P. Fitzpatric, F.N. Smith and P.W. Jaffery, The Aluminium - Air Battery SAE Meeting, Detroit, Michigan, Feb.8 - Mar. 4, [6] T. Jeyaraj, C. Raja and V.V. Dhayabaran, Transactions of the SAEST 37(1), 5 (). [7] Dhayabaran, V.V., Merlin, J.P., Lydia, I.S., Shanthi, R. and Sivaraj, R., 4. Inhibition of corrosion of aluminium in presence of fluorescein in basic medium. Ionics, 1(3), pp.889. [8] G. Moretti, F. Guidi, G. Grion, corros. sci. 46(6) 387. [9] Nancharaiah, T., Nagabhushanam, M. and Nagendram, B.A., 13. Process parameters optimization in SLS process using design of experiments. IJMET, 4(), pp [1] Ganesan, H. and Mohankumar, G., 11. Study on optimization of machining parameters in turning process using evolutionary algorithm with experimental verification. IJMET, (1), pp editor@iaeme.com