F-KCW-Department Publications
Permanent URI for this communityhttps://dspace.psgrkcw.com/handle/123456789/1
Browse
8 results
Search Results
Item ANTI-CORROSION PROPERTIES OF BENZOTHIAZOLE DERIVATIVES FOR MILD STEEL IN 1M H2SO4 SOLUTION(Chemical Science Review and Letters, 2014) Hemapriya V; Parameswari K; Chitra SThe corrosion inhibition performance of benzothiazole derivatives namely, 2-phenylbenzothiazole(PBT), 2-(4- methoxy-phenyl)benzothiazole(MPB) and 2-(3,4,5- trimethoxy-phenyl)benzothiazole(TPB) on mild steel in 1M H2SO4 has been studied by weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy. The experimental results showed that the inhibition efficiency increases with increase in inhibitor concentration but decreases with increasing temperature. The inhibition has been assumed to occur via adsorption of inhibitors on mild steel surface. This is supported by the results obtained from scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. Adsorption of inhibitors on mild steel surface follows Langmuir adsorption isotherm. The activation energy and free energy of adsorption for the inhibition reaction support the mechanism of physical adsorption. Potentiodynamic polarization measurements indicate that the studied benzothiazole derivatives act as mixed inhibitors. Quantum chemical calculations have been performed and quantum chemical indices were calculated to supplement the experimental results.Item RECENT REVIEWS ON QUINOLINE DERIVATIVES AS CORROSION INHIBITORS(De Gruyter, 2018-02-21) Lavanya K; Saranya J; Chitra STraditionally, controlling corrosion has been managed by various methods like cathodic protection, process control, reduction of the metal impurity content and application of surface treatment techniques as well as incorporation of suitable alloys. However, the use of corrosion inhibitors has proven to be the easiest and cheapest method for corrosion protection and prevention in acidic media. These inhibitors slow down the corrosion rate and thus prevent economic losses due to metallic corrosion on industrial vessels, equipment or surfaces. Many researchers have recently focused on corrosion prevention methods using organic inhibitors for mild steel in acidic solutions to mimic industrial processes. This paper arranges for an overview of types of corrosion, corrosion process and mainly recent work done on the application of quinolone derivatives as corrosion inhibitors for different metalsItem SOYA BEAN OIL BASED POLYURETHANES FOR CORROSION INHIBITION OF MILD STEEL IN ACID MEDIUM(Taylor & Francis, 2015-11-13) Valarmathi E; Saranya J; Sounthari P; Parameswari K; Chitra SPolyurethanes synthesized from soya bean oil were characterized by Fourier-transform infrared spectroscopy, scanning electron microscopy (SEM), X-ray diffraction and energy-dispersion X-ray analysis methods. Thermal stability of the polyurethanes was investigated by thermogravimetric analysis. The corrosion inhibition effect of polyurethanes on mild steel in 1 M H2SO4 was studied using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy methods. The effect of temperature on the corrosion behaviour of mild steel was studied in the temperature range (303–333 K) with optimum inhibitor concentration. The adsorption of the inhibitors was found to obey the Langmuir adsorption isotherm. It was found that the inhibition efficiency increased with increase in concentration but decreased with increase in temperature. The associated activation energy and other thermodynamic parameters such as adsorption–desorption equilibrium constant (Kads), standard free energy of adsorption (ΔG◦ads), enthalpy of adsorption (ΔH◦ads) and entropy of adsorption (ΔS◦ads) were calculated to elaborate the corrosion inhibition mechanism. Surface morphology of the mild steel plate immersed in 1 M H2SO4 was characterized by SEM and AFM techniques.Item QUANTUM CHEMICAL STUDY ON THE CORROSION INHIBITION PROPERTY OF SOME HETEROCYCLIC AZOLE DERIVATIVES(Oriental Scientific Publishing Company, 2015-08-20) Anusuya N; Sounthari P; Saranya J; Parameswari K; Chitra SQuantum chemical calculations based on density functional theory (DFT) method were performed on heterocyclic azole derivatives as corrosion inhibitors for mild steel in acid media to investigate the relationship between molecular structure of the inhibitors and the corresponding inhibition efficiencies (%). Quantum chemical parameters most relevant to their potential action as corrosion inhibitors have been calculated in the non-protonated and protonated forms in aqueous phase for comparison. Results obtained in this study indicate thatin acidic media, both the protonated and non-protonated forms of the azoles represent the better actual experimental situation.Item INHIBITION EFFECTS AND THEORETICAL STUDIES OF PYRAZOLIDINE-DIONES AS CORROSION INHIBITORS FOR MILD STEEL IN 1M H2SO4 SOLUTION(INPRESSCO, 2014-12-01) Hemapriya V; Saranya P; Parameswari K; Chitra SCorrosion inhibition of mild steel in the presence of different concentrations of 1-phenylpyrazolidine-3,5dione(PPD)and4-(4-benzylidine)-1-phenylpyrazolidine-3,5-dione(BPP) in 1M H2SO4 solution has been studied using weight loss, potentiodynamic polarization and electrochemical impedance spectroscopy. The effect of temperature on the corrosion behavior of mild steel has been examined in the temperature range of 303–333 K. The inhibition efficiency increases with increasing inhibitor concentration but decreases with increasing temperature. The activation energy and free energy of adsorption for the inhibition reaction support the mechanism of physisorption. The adsorption of inhibitors on mild steel surface is endothermic, spontaneous and consistent with the Langmuir adsorption isotherm. Potentiodynamic polarization measurements indicate that PPD & BPP act as mixed inhibitors. Surface analysis of mild steel has been carried out using scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy which reveals the adsorption of inhibitors on mild steel surface. Quantum chemical calculations have been performed at B3LYP/6-31G(d,p) level to calculate the electronic properties of the molecules inorder to complement the experimental results. The optimized structures, position of HOMO and LUMO of the molecules are obtained.Item EXPERIMENTAL AND QUANTUM CHEMICAL STUDIES ON THE INHIBITION POTENTIAL OF SOME QUINOXALINE DERIVATIVES FOR MILD STEEL IN ACID MEDIA(Oriental Scientific Publishing Company, 2014-11-15) Saranya J; Kiruthika A; Sounthari P; Saranya G; Parameswari K; Chitra SThe inhibition potential of four Quinoxaline derivatives namely 1,4-dihydroquinoxaline-2,3-dione, (3E)-3-hydrazinylidene-3,4-dihydroquinoxalin-2(1H)-one, 1-[(2E)-3-oxo-3,4-dihydroquinoxalin-2(1H)-ylidene]urea and 1-[(2E)-3-oxo-3,4-dihydroquinoxalin-2(1H)-ylidene]thiourea have been investigated against mild steel in 1M H2SO4 solution using conventional weight loss, electrochemical impedance spectroscopy, potentiodynamic polarization and atomic absorption spectroscopy. The percentage inhibition efficiency was found to increase with increase in the inhibitor concentration due to the adsorption of the inhibitor molecules on the metal surface. In addition, it was established that the adsorption follows Langmuir adsorption isotherm. Moreover, some thermodynamic data were calculated and discussed. The density functional theory at the B3LYP/6-311G (d,p) basis set level was performed for two inhibitors namely 1,4-dihydroquinoxaline-2,3-dione and (3E)-3-hydrazinylidene-3,4-dihydroquinoxalin-2(1H)-one. The quantum chemical parameters such as highest occupied molecular orbital energy (EHOMO), lowest unoccupied molecular orbital energy (ELUMO), energy gap (∆E), dipole moment (µ), softness (σ), hardness (η), electronegativity (χ), Mulliken atomic charges, the fraction of electrons transferred from the inhibitor to the metal surface (∆N) and the total energy (TE) have been calculated for these compounds. It was found that theoretical data support the experimental results.Item DIANILINE SCHIFF BASES AS INHIBITORS OF MILD STEEL CORROSION IN ACID MEDIA(ESG, 2010-11-01) Chitra S; Parameswari K; Selvaraj AA new class of corrosion inhibitors namely dianiline Schiff bases was synthesized and its inhibiting action on the corrosion of mild steel in 1M sulphuric acid at 30°C was investigated by various corrosion monitoring techniques. A preliminary screening of the inhibition efficiency was carried out using weight loss measurements. Potentiodynamic polarization studies showed that the Schiff bases were mixed type inhibitors. The effect of temperature on the corrosion behaviour of mild steel in 1M sulphuric acid with the addition of the Schiff bases was studied in the temperature range from 40°C-60°C. The adsorption of these compounds on a mild steel surface from sulphuric acid obeyed the Langmuir adsorption isotherm. The decrease in inhibition efficiency with increase in temperature and the less negative ∆G°ads values suggest predominant physisorption of the Schiff base molecules on the steel surface.Item CORROSION INHIBITION AND ADSORPTION BEHAVIOUR OF THIADIAZOLE DERIVATIVES ON MILD STEEL IN ACID MEDIUM: EXPERIMENTAL AND THEORETICAL STUDIES(Sricreeper Technologies/Indian Institute of Technology Madras, 2015) Saranya J; Sounthari P; Chitra SThe anticorrosion potential of thiadiazole derivatives on mild steel in 1 M H2SO4 medium has been studied using weight loss method and surface analysis at 303 K-333K. The inhibition efficiency was found to increase with increasing concentration of the inhibitors but decreased with increase in temperature, which is attributed to physisorption. The adsorption of the inhibitors on the mild steel surface obeyed the Langmuir adsorption isotherm. Various kinetic and thermodynamic parameters reveal a weak interaction between inhibitor and mild steel surface. Further, scanning electron microscope (SEM) and atomic force microscope (AFM) analyses supported the inhibitive action of the inhibitors by the formation of protective layer over the mild steel surface. Quantum chemical method was employed for theoretical calculations and the obtained results were found to be consistent with experimental findings.