Inhibition Efficiency Of N-Cetyl-N, N, N-Trimethyl .

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July 2011Entire Research, Vol.-3, Issue-III1Inhibition Efficiency of N-Cetyl-N, N, N-TrimethylAmmonium Bromide on 304 Stainless Steel in NaClSolutionDr. R. S. Dubey: Chemistry Research Laboratory, Dept. of Chemistry, R. J.College of Arts, Science and Commerce (University of Mumbai), Ghatkopar (W),Mumbai-400 086, India.AbstractN-Cetyl-N, N, N-Trimethyl Ammonium Bromide (CTAB)-C19H42NBr is usedas corrosion inhibitor for protection of 304 Stainless Steel in 1.5% NaCl solution.The inhibition effect of the compound was investigated by using electrochemicalpolarization techniques i.e. potentiodynamic and open circuit potential in theconcentration ranges 5-50ppm. Scanning electron microscope (SEM) examinedthe changes in surface morphology of the specimen in absence and presence ofthis inhibitor. The results obtained reveals that N-Cetyl-N, N, N-TrimethylAmmonium Bromide is a very good corrosion inhibitor and shows bestperformance at a very low concentration of 15 ppm. Potentiodynamic curvesindicate, that compound is a mixed type of inhibitors having heteroatom in thechain of the compound. SEM observations also show that in the presence ofinhibitor, there is less attack of the metal surface.Keywords: Corrosion, 304 Stainless Steel, Inhibitors, and Electrochemicaltechniques.IntroductionCoatings, paints and use of organic compounds are the some way ofcorrosion mitigation. The organic compounds especially, heterocyclic compoundscontaining heteroatoms like S, N, O, Se with loosely bound lone pair of electronsand compounds with π electrons, undergo adsorption on the metal surface andprotects the material from the aggressive environment. Various workers haveused organic compounds for corrosion inhibition of metals like Cu, iron, mild steel,and stainless steel, Al etc. at different concentrations in acidic, basic and saltsolutions1-11. Stainless steel, due to its high strength, workability and highcorrosion resistance property are used in various engineering applications likechemical and pharmaceutical industry 12-13, food and beverage industry14,petrochemical industry15-17, oil and water pipe lines18, ship andNaval structures 19-20; architectural applications, water supply anddesalination plants 13.The corrosion inhibition actions of the organic compounds containingheteroatoms such as undecanoic acid hydrazide, 2-mercaptobenzothiazole, and2-hydrazinobenzothiazole on carbon steel in HCl solution21, morpholiniumcaprylate, morpholinium sebacate and laurate22-23, morpholinium oleate24 andmorpholinium stearate25 have been investigated for steel. Al-Suhybani et al26investigated the corrosion inhibition efficiency of azoles: 2-mercaptobenzoazole(CBA), and its derivatives (2-mercaptobenzoimidazole, 2-mercaptobenzoxazole,ISSN 0975-5020

July 2011Entire Research, Vol.-3, Issue-III22-mercapto benzothiazole); 2-methyl benzoazole and its derivatives (2-methylbenzimidazole, 2-methyl benzoxazole, 2-methyl benzothiazole and 2-methylbenzoselenazole) for 304 stainless steel in acidic solution where some providesinhibition efficiency up to 90% at a concentration of 5x10 -4 M and stated efficiencyof the heteroatoms in the decreasing order as Se S N O. Dubey et al27-28investigated the corrosion inhibition efficiency of some heterocyclic organiccompounds like Ketoconazole, Fluconazole, Roxythromycin, Amoxycillin,Ampicillin; and some benzimidazole derivatives like 2-methylbenzimidazole, 2ethylbenzimidazole, and 2-benzylbenzimidazole for 304 stainless steel in marineenvironment. The aim of the present investigation was to find out the suitableinhibitor for control of corrosion of 304 stainless steel in marine environment.Experimental Procedure:304 Stainless Steel of commercial grade in sheet form having compositionas follows: C -0.06%, Si - 0.53%, Mn- 0.10%, P- 0.032%, S-0.016%, Ni8.16%, Cr- 18.17%; and Iron- balance, were used in the present investigation.For electrochemical polarization, samples of 1cm x 3cm were sheared fromthe commercial grade sheets. The surface of these samples was successivelypolished by using the Emery papers of grades 1 / 0, 2 / 0, 3 / 0, and 4 / 0obtained from Sianor, Switzerland to obtain a scratch free mirror finish surface.The polished samples were washed with detergent solution, rinsed withdistilled water and finally degreased with acetone. The specimens were driedand stored in a desiccators containing silica gel as a dehydrating agent.N-Cetyl-N, N, N-Trimethyl Ammonium Bromide was procured and itsinhibition efficiency was determined with electrochemical techniques. A molecularstructure of this compound is shown in Fig.1.Fig.1.Structure of N-Cetyl-N,N,N-trimethyl ammonium bromidePure NaCl obtained from S. D. Fine Chemicals was used to prepare its1.5% solution with double distilled water.Electrochemical Measurement System, DC 105, containing software of DCcorrosion techniques from M/S Gamry Instruments Inc., (No. 23-25) 734, LouisDrive, Warminster, PA-18974, USA has been used for performing corrosionpotential and polarization experiments.For electrochemical polarization studies (corrosion potential, andpotentiodynamic polarization) flag shaped specimens with sufficiently long tailwere cut from the stainless steel sheet. These samples were polished asdescribed earlier leaving a working area of 1cm 2 on both sides of the flag and asmall portion at the tip for providing electrical contact. Rest of the surface wasisolated from the corroding solution by coating with enamel lacquer including sideedges. The test specimen was connected to the working electrode holder with theISSN 0975-5020

July 2011Entire Research, Vol.-3, Issue-III3help of a screw. About 50ml of the corrosive medium was taken in a minicorrosion testing electrochemical cell. This volume was appropriate to permitdesired immersion of electrodes. The electrochemical investigation was carriedout using microprocessor based corrosion measurement system (CMS-105,Gamry Instruments Inc., USA.). The three-electrode i.e. working electrode,reference electrode (calomel), and counter electrode (graphite rod), system cellwas used throughout the electrochemical measurements. Open circuit potentialmeasurement and potentiodynamic polarization of the samples were investigatedin the concentration ranges 5 , 10 ,15 ,20 ,30 , 40 and 50 ppm of the inhibitors.The value of inhibition efficiency in terms of corrosion current density:E 100 x (io – i) / io . .1Where io and i are the corrosion current density of the uninhibited andinhibited samples.Scanning Electron Microscopy (SEM)Surface morphology of the specimens before and after corrosionexperiments was examined using the scanning electron microscope (Model No.JEOL-JSM 840, JAPAN).Results and Discussion:Open circuit potential (OCP)Open circuit potential (potential vs. time) plots for 304 Stainless steelxposed to 1.5%NaCl in absence and presence of N-Cetyl-N, N, N-trimethylmmonium bromide as inhibitor in the concentration range 5-40ppm is shown inFig.2.In presence of inhibitor the potential shifts towards more positive direction incompare to the blank (Curve No.7). The potential shift in ve direction ismaximum corresponding to the conc. 15ppm.Fig. 2. Open Circuit Potential of 304 Stainless Steel Exposed to 1.5% NaClSolution with different concentrations (in ppm) of N-Cetyl-N, N, N-TrimethylAmmonium Bromide.Potentidynamic polarizationPotentiodynamic polarization (potential vs. current density) consisting ofanodic and cathodic polarization curves is recorded and indicates the partialISSN 0975-5020

July 2011Entire Research, Vol.-3, Issue-III4electrochemical reactions i.e. anodic and cathodic reactions. Fig.3. Shows thepotentiodynamic polarization curves of 304 Stainless steel exposed to 1.5% NaClsolution with presence of N-Cetyl-N, N, N-trimethyl ammonium bromide in theconc. ranges 5-50 ppm and in the absence of the inhibitor.Fig. 3. Potentiodynamic polarization of 304 Stainless Steel Exposed to1.5% NaCl Solution with different concentrations (in ppm) of N-Cetyl-N, N, NTrimethyl Ammonium Bromide.In presence of inhibitor the potential shifts towards the nobledirection and decreasing simultaneously the corrosion current density, indicatesthe interference of the inhibitor to the anodic and cathodic reaction processes.The effect of different concentration of the inhibitor on various electrochemicalparameters like corrosion potential (Ecorr), corrosion current density (Icorr), anodicTafel constant (βa), cathodic Tafel constant (βc), corrosion rate and % inhibitionefficiency etc. of 304 Stainless steel is shown in Table-1.Among all the conc. of the inhibitor, 15ppm is the optimum concentration,which gives highest % inhibition efficiency (98.05%), lowest anodic Tafel‘s slope(218.7e-3 V/decade) and highest noble corrosion potential (79.00 mV).Table-1. Electrochemical Parameters for Inhibition of Corrosion of 304Stainless Steel Exposed to 1.5% Sodium Chloride with DifferentConcentration of N-Cetyl-N, N, N-Trimethyl Ammonium Bromide.Concentration a cIcorrEcorrCorr. Rate )Efficiency-737.7e-3171.0e-31.930-317.0N-Cetyl-N, N, N-Trimethyl Ammonium Bromide5246.2e-3235.0e-3 0.07940-34.1010394.5e-3266.9e-3 0.0830021.0015218.7e-3242.6e-3 0.0 376079.0020236.3e-3149.1e-3 0.03780-11.1030252.0e-3167.0e-3 0.08660-33.20ISSN 6.77e-395.8895.7098.0598.0495.51

July 2011Entire Research, Vol.-3, Issue-III54050243.4e-3216.0e-3 0.0821018.9034.83e-395.74565.3e-3185.9e-3 0.47700 -247.0 202.4e-375.28Conclusion: N-Cetyl-N, N, N-trimethyl ammonium bromide acts as anexcellent corrosion inhibitor for 304 stainless steel in 1.5% sodium chloridesolution. Optimum concentration, which gives highest percentage inhibitionefficiency (98.05%), was 15ppm. Inhibition may be due to adsorption of inhibitoron the surface of 304 stainless steel which act as a barrier between environmentand the metal surfaceAcknowledgementThe author would like to thank the Department of Science and Technology(DST), Ministry of Science and Technology, Government of India for sanctioningthe research grant.ReferencesM. Zaky, F. H. Assaf, Br. Corros. J. 37(1) (2002): p. 48-55.R. D. Armstrong, J. A. Harrison, H.R. Thirsk, Corros. Sci. 108 (1970): p. 679R. D.K. Misra, Electrochem. Acta 31 (1986): p. 51D. Chebabe, Z. A. Chikh, N. Hajjaji, A. Srhiri, F. Zucchi, Corros. Sci., 45(2003): p. 309-320.5. H. Luo, Y. G. Guan, K. N. Han, Corrosion 54 (1998): p. 721,6. J. Vosta , N. Hackerman, Corros. Sci. 30(1990): p. 9497. G. Quartarone, T. Bellomi, A. Zingales, Corros. Sci. 45 (2003): p. 715-7338. P. G. Abdul-Ahad, S. H. F. Al-Madfai, Corrosion 45 (1989): p.9789. W. J. van Ooji, and S. Zhu, Corrosion 57(5) (2001): p. 41710. S.L.Li, H. Y. Ma, S.B.Lei, R.Yu, S.H. Chen, D.X. Liu, Corrosion 54(1998):p.94711. Z. Quan, X. Wu, S. Chen, S. Zhao, H. Ma, Corrosion 57(3) (2001): p. 195-201.12. R. J. Valentine, ASM Handbook Corrosion, 6th Ed, Vol. 13 (1998): p.1225.13. G. Gemmel, Applications of Stainless Steel, Vol.2, 9-11 June 1992,Stockholm, Sweden. p. 661-672,[in English]. METADEX: 199307-61-074014. E. W. Dreyman, ASM Handbook Corrosion, 6th Eds: Vol. 13(1998): p. 122115. B. B. Morton, Metallurgical methods for Combacting Corrosion and Abrasion inthe Petroleum Industry, J. Inst. Petrol. 34 (239) (1948): p.1-6816. E. L. Hildebrand, Materials Selection for Petroleum Refineries andPetrochemical Plants, Mater. Prot. Perfor. 11 (7) (1972): p.19-2217. The Role of Stainless Steel in Petroleum Refining, American Iron and SteelInstitutes, 1977.18. J. M. Ramero, C. A. Chavez, L. Martinez, M. Amaya, Br. Corros. J. 37(2)(2002): p. 117-12119. A.J. Sedriks , P. Dudts, Corrosion 57(1) (2001): p. 84-9120. M. von Bour, Naval Forces, 18(6) (1997): p. 9821. M. Athar, H. Ali, M. A. Quraishi, Br. Corros. J. 37(2002): p. 1551.2.3.4.***ISSN 0975-5020

July 2011Entire Research, Vol.-3, Issue-III6FDI and FII Impact on BSE Sensex: Reality and MythRajan J. Nandola: Research Scholar, Thakur College of Science and CommerceAbstractOne of the outstanding features of globalization in the financial servicesindustry is the increased access provided to non-local investors in several majorstock markets of the world. Increasingly, stock markets from emerging marketspermit institutional investors to trade in their domestic markets. Indian stockmarket opened to Foreign Institutional Investors in 14th September 1992, initiallywith lot of restrictions. The regulation on them are liberalized and minimized now,since 1993 has received a considerable amount of portfolio investment fromforeigners in the form if FIIs investment in equities. This has become a turningpoint of India stock market. The government of India announced the policy of thegovernment to permit the FII investment in India capital market. According to theSEBI modified the regulation on 14-11-1995. In order to make investment in Indiaequity market they wanted to register with Security Exchange Board of India asforeign institutional investors. It is possible for foreigners to trade in Indiasecurities without registering as Foreign Institutional investors, but such casesrequire approval from Reserve Bank of India or the Foreign Institutional PromotionBoard. They are generally concentrated in secondary market. Portfolio flows oftenreferred to as ‗hot- money‘ are notoriously volatile capital flows. They have alsoresponsible for spreading financial crisis causing contagion in internationalmarket. Evan though, the FIIs have been playing a key role in the financialmarkets since their entry into this country. The explosive portfolio flow by FIIbrings with them great advantages as they are engine of growth, lowering cost ofcapital in many emerging market. This opening up of capital markets in emergingmarket countries has been perceived as beneficial by some researchers whileothers are concerned about possible adverse consequences. The past two yearshave been highly turbulent for the world economy which has been hit hard by aprofound financial crisis. It is being apprehended as the worst ever crisis to hit theworld economy since the Great Depression of 1930‘s. Rumors are flying thick andpeople all around the world are gripped with a sense of fear and panic. The Indianeconomy has been growing at an impressive rate in the past few years. Growth isbeing registered at an average of around 9% for the past three years. Along withChina, India is emerging as a one of the most attractive destinations forinvestment for entrepreneurs worldwide. This paper is to study the impact of FDIand FII on BSE Stock exchange over a period of liberalization through regressionanalysis and using R-software to show whether really the FDI and FII is having amajor impact on the Sensex or it is just because of panic situation the downfalloccurred. This paper will give you the clear picture of what actually has impactedthe Sensex foreign investors or panic?PreambleOne of the outstanding features of globalization in the financial servicesindustry is the increased access provided to non-local investors in several majorISSN 0975-5020

July 2011Entire Research, Vol.-3, Issue-III7stock markets of the world. Increasingly, stock markets from emerging marketspermit institutional investors to trade in their domestic markets. Indian stockmarket opened to Foreign Institutional Investors in 14th September 1992, initiallywith lot of restrictions. The regulation on them are liberalized and minimized now,since 1993 has received a considerable amount of portfolio investment fromforeigners in the form if FIIs investment in equities. This has become a turningpoint of India stock market. The government of India announced the policy of thegovernment to permit the FII investment in India capital market. According to theSEBI modified the regulation on 14-11-1995. In order to make investment in Indiaequity market they wanted to register with Security Exchange Board of India asforeign institutional investors. It is possible for foreigners to trade in Indiasecurities without registering as Foreign Institutional investors, but such casesrequire approval from Reserve Bank of India or the Foreign Institutional PromotionBoard. They are generally concentrated in secondary market. Portfolio flows oftenreferred to as ‗hot- money‘ are notoriously volatile capital flows. They have alsoresponsible for spreading financial crisis causing contagion in internationalmarket. Evan though, the FIIs have been plying a key role in the financial marketssince their entry into this country. The explosive portfolio flow by FII brings withthem great advantages as they are engine of growth, lowering cost of capital inmany emerging market. This opening up of capital markets in emerging marketcountries has been perceived as beneficial by some researchers while others areconcerned about possible adverse consequences.Objectives of the Study To study the significance of FII and FDI on BSE Sensex. To study the relationship between the FII and BSE Sensex usingregression Model. To examine whether FIIs were a reason for disturbance into the Indianstock market. The R software tool was used to analyze the relationship of FDI and FII onthe BSE Sensex. To study whether policy liberalization had an impact on FII. To study the subsequent downfall and revamping policy to protect themarket.Hypotheses Generation SENSEX α β1total(di pi) ε SENSEX α β2di ε SENSEX α β3pi ε Null Hypothesis (H0)β1 β2 β3 β4 0 Alternative Hypothesis(Hα)β1 β2 β3 β4 0MethodologyISSN 0975-5020

July 2011Entire Research, Vol.-3, Issue-III8 Sensex Index (Base:1978-79 100) , Direct Investment and PortfolioInvestment data were taken for 19 yrs (from 1990-9991 to 2009-10). Data was collected from secondary sources like Reserve Bank of Indiawebsite ,website of SEBI & Indian Foreign Investment Policy.( Centre AsieIfri ) Regression analysis was done using R Software.BackgroundY V Reddy: Indian economy - current status and select issues: it is wellrecognized that giving better incentives to foreign investors over domesticinvestors results in scope for ―round-tripping‖ and inefficiencies. Similarly, ifavenues for portfolio flows or equity-transfers from domestic to foreign investorsare easily available and attractive, the flows under FDI defined in terms of addingto domestic production-capacities will tend to be smaller. Attention to these maysimultaneously address micro or institutional issues relating to corporates,volatility issues relating to capital flows and financial markets, and above allensure high-quality inflows of foreign savings which is more important to ourcountry at this stage of development, to provide a healthy supplement to thedomestic savings.Consolidated Fdi Policy (Effective From April 1, 2010) Government ofIndia,Ministry of Commerce & Industry,Department of Industrial Policy &Promotion,(FC Section)A non-resident entity (other than a citizen of Pakistan or an entityincorporated in Pakistan)can invest in India, subject to the FDI Policy. A citizen of Bangladesh or anentity incorporated in Bangladesh can invest in India under the FDI Policy, onlyunder the Government route. NRIs resident in Nepal and Bhutan as well ascitizens of Nepal and Bhutan are permitted to invest in the capital of Indiancompanies on repatriation basis, subject to the condition that the amount ofconsideration for such investment shall be paid only by way of inward remittancein free foreign exchange through normal banking channels. OCBs have beenderecognized as a class of Investors in India with effect from September 16,2003.Erstwhile OCBs which are incorporated outside India and are not under theadverse notice of RBI can make fresh investments under FDI Policy asincorporated non-resident entities, with the prior approval of Government of Indiaif the investment is through Government route; and with the prior approval of RBIif the investment is

50 565.3e-3 185.9e-3 0.47700 -247.0 202.4e-3 75.28 Conclusion: N-Cetyl-N, N, N-trimethyl ammonium bromide acts as an excellent corrosion

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