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1.
Artabotrys odoratissimus inhibitory effect on mild steel (MS) corrosion in 0.5 M H2SO4 solution has been assessed utilizing mass loss, electrochemical potentiodynamic polarization, and impedance spectroscopy techniques. The Artabotrys odoratissimus plant has a wide range of bioactive compounds. Phytochemicals were tested for ethanolic Artabotrys odoratissimus leaves extract (AOLE) using the FeCl3 test, Salkowaski's test, and others. Corrosion tests were conducted at varying inhibitor concentrations and temperatures. The inhibitory impact of AOLE on corrosion of MS was reported to improve with increasing concentration. Polarization experiments revealed that AOLE is a mixed kind of inhibitor and the inhibition efficacy (ηw) for MS is 93.27% for 1.25 g/L AOLE. For Electrochemical impedance spectroscopy (EIS), maximal inhibitory efficacy (ηw) was 91.62% due to AOLE adsorption on the MS surface. The obtained results using each methodology are highly consistent and closely resemble each other. The adsorption of AOLE molecules on an MS surface from the bulk of the solution causes the inhibitor's inhibition action, and the adsorption mechanism follows Langmuir adsorption isotherm. The computed values ranged between ?32.919 and ?33.520 kJ mol?1, implying a spontaneous and exothermic inhibitory action. The thermodynamic and activation parameters are often used to understand corrosion inhibition mechanisms. The comparison of corrosion product and pure extract FT-IR spectrum indicates the nature of AOLE adsorption on the MS surface. The surface morphology of MS samples was assessed using atomic force microscopy (AFM), scanning electron microscope (SEM), and contact angle techniques. 相似文献
2.
A. Rodríguez Torres M. G. Valladares Cisneros 《Green Chemistry Letters and Reviews》2016,9(3):143-155
A study on the use of the methanol extract of Medicago sativa as a green corrosion inhibitor for 1018 carbon steel in 0.5?M of sulfuric acid has been carried out by using potentiodynamic polarization curves, electrochemical impedance spectroscopy and gravimetric tests. Testing temperatures were 25°C, 40°C and 60°C. Results showed that M. sativa is a good corrosion inhibitor, with its efficiency increasing with its concentration and with time, but decreasing with the temperature. M. sativa forms a passive film on top of the steel with a passive current density and pitting potential values lower than that for uninhibited solution, and remained on the steel for 8–12?h. This film formed by iron ions and heteroatoms present in OH? and amine groups from the extract are adsorbed on the steel and form a protective film on to the steel. 相似文献
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4.
Bhuvaneswari Thirumangalam Karunanithi 《Journal of Dispersion Science and Technology》2013,34(10):1441-1450
AbstractThe present study investigated the adsorption and inhibition behavior of leaf extract of Tephrosia Purpurea (T. purpurea) on mild steel corrosion in 1?N H2SO4 solution using electrochemical and surface morphological methods. Techniques adopted for electrochemical studies were Potentiodynamic Polarization and Electrochemical Impedance Spectroscopy (EIS) technique; and surface morphological studies were carried out using Scanning Electron Microscopy (SEM), and Atomic Force Microscopy (AFM). The leaf extract of T. purpurea was characterized using UV-Visible spectroscopy (UV-Vis), Fourier-Transform Infrared Spectroscopy (FT-IR), Nuclear Magnetic Resonance Spectroscopy (NMR) and Gas Chromatography – Mass Spectrometry (GCMS). The results obtained from electrochemical studies exhibited the potential of T. purpurea as good corrosion inhibitor. And, it was found that, the inhibition efficiency (I.E in %) increases with increase in concentration of the inhibitor molecules, the optimum inhibitor concentration observed was 300?ppm and the inhibition efficiency of 93% was observed at this inhibitor concentration. Above 300?ppm, there was not much changes in inhibition efficiency. Polarization studies provided the information that the inhibition is of mixed type and EIS confirmed that the corrosion process is controlled by single charge transfer mechanism. And, it was obtained that, the adsorption of inhibitor molecules obeys Langmuir adsorption isotherm. The inhibition is mainly by the adsorption of inhibitor molecules on the mild steel electrode surface, which was confirmed by FT-IR, SEM and AFM studies. Through all the experimental results, it can be arrived that, the leaf extract of T. purpurea performed as a good corrosion inhibitor for mild steel in 1?N sulfuric acid medium. 相似文献
5.
The inhibitory action of an extract of Hemidesmus indicus leaves as a potential corrosion inhibitor for steel in H2SO4 solutions was examined using conventional mass loss, gasometric techniques, electrochemical polarisations and electrochemical impedance spectroscopy. The results revealed that the extract of Hemidesmus indicus leaves performed well as an inhibitor for the corrosion of the metal employed in an accelerating medium. The inhibition efficiencies for all the experimental techniques employed increased with increasing the concentration of the plant extract but decreased with a rise in temperature. Both the cathodic hydrogen evolution and the anodic dissolution of mild steel were inhibited, hence the active molecule of the extract studied acted as a mixed-type corrosion inhibitor. 相似文献
6.
《Green Chemistry Letters and Reviews》2013,6(2):111-119
Abstract The inhibitive and adsorptive characteristics of ethanol extract of Gnetum Africana for the corrosion of mild steel in H2SO4 solutions have been studied using weight loss, gasometric, thermometric, and IR methods of monitoring corrosion. Ethanol extract of Gnetum Africana is a good adsorption inhibitor for the corrosion of mild steel in H2SO4. The inhibitive property of the extract is attributed to the presence of alkaloid, saponin, tannin, terpene, anthraquinone, cardiac glycoside, and alkaloid in the extract. The adsorption of the inhibitor on mild steel surface is exothermic, spontaneous and is consistent with the mechanism of physical adsorption. In addition, Langmuir and Temkin adsorption isotherms best described the adsorption characteristics of the inhibitor. Efforts to improve the adsorption of the inhibitor through synergistic combinations with halides indicated that only KCl may enhance the efficiency of the inhibitor. The study provides information on the use of ethanol extract of Gnetum Africana as a corrosion inhibitor for mild steel. 相似文献
7.
The synergistic action caused by iodide ions on the corrosion inhibition of mild steel in 1 M H2SO4 by leaves and stem extracts of Sida acuta was studied using weight loss and hydrogen evolution methods at 30–60 °C. It was found that the leaves and stem extracts of S. acuta inhibited the acid induced corrosion of mild steel. Addition of iodide ions enhances the inhibition efficiency to a considerable extent. The inhibition efficiency increases with increase in the iodide ion concentration but decreases with rise in temperature. Adsorption of the extracts alone and in combination of iodide ion was found to obey Freundlich adsorption isotherm at all temperatures studied. Inhibition mechanism is deduced from the temperature dependence of the inhibition efficiency as well as from assessment of kinetic and activation parameters that govern the processes. The synergism parameter (S1) is defined and evaluated from the inhibition efficiency values. This parameter for the different concentrations of iodide ions from the two techniques employed is found to be greater than unity indicating that the enhanced inhibition efficiency of the extracts caused by the addition of iodide ions is due to synergism. 相似文献
8.
《Arabian Journal of Chemistry》2020,13(11):7744-7758
In present study, an isoxazole derivative, namely, (Z)-4-(4-hydroxy-3-methoxybenzylidene)-3-methylisoxazol-5(4H)-one referred here as (IOD) has been studied as an environment-friendly corrosion inhibitor for mild steel (MS) in acidic medium (1 M HCl). The present work was investigated by gravimetric, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization (PDP), fourier-transform infrared (FT-IR) spectroscopy techniques. Atomic force microscopy (AFM), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy (EDS) confirmed the surface morphologies of the MS surface with and without IOD in the acid medium. The inhibition efficiency (I.E.) of IOD was increased by rising its concentration attaining maximum value (96.6%) at 300 ppm at 30 °C and decreases with increasing temperature from 30 °C to 60 °C. The adsorption of studied inhibitor followed Langmuir adsorption isotherm model. The PDP study revealed that the IOD acts as a mixed-type inhibitor with predominating anodic effect. The EIS study confirmed that increasing IOD concentration enhances the charge transfer resistance (Rct) and then reduces the double layer capacitance (Cdl) owing to the development of a protective layer on the MS surface. 相似文献
9.
The inhibitive action of ethanol extracts from leaves (LV), bark (BK) and roots (RT) of Nauclea latifolia on mild steel corrosion in H2SO4 solutions at 30–60 °C was studied using weight loss and gasometric techniques. The extracts were found to inhibit the corrosion of mild steel in H2SO4 solutions and the inhibition efficiencies of the extracts follow the trend: RT > LV > BK. The inhibition efficiency increased with the extracts concentration but decreased with temperature rise. Physical adsorption of the phytochemical components of the plant on the metal surface is proposed as the mechanism of inhibition. The adsorption characteristics of the inhibitor were approximated by the thermodynamic-kinetic model of El-Awady et al. 相似文献
10.
D. Gopi R. Saraswathy G. Athithya L. Kavitha Jeong‐Heo Bae Dae–Kyeong Kim 《Surface and interface analysis : SIA》2012,44(10):1331-1337
In this paper, we have reported the anti‐corrosion performance of ceria / poly (indole‐co‐pyrrole) (Ce/(poly(In‐co‐Py)) bilayer coating on low nickel stainless steel (LN SS). Electrochemical polymerization of (poly (In‐co‐Py)) was achieved on ceria‐coated LN SS (CeO2/LN SS) in acetonitrile medium containing LiClO4 (ACN‐LiClO4) by cyclic voltammetric technique. The coatings were characterized by analytical techniques like Fourier transform infrared spectroscopy, scanning electron microscopy with energy dispersive analysis of X‐ray, respectively. The mechanical behavior of the coatings was studied using peel test, hardness and wear resistance tests. The corrosion defensive performance of this bilayer coating on LN SS was investigated using electrochemical techniques such as potentiodynamic polarization and electrochemical impedance spectroscopy in 0.5 M H2SO4. These results show that the bilayer coating on LN SS lowered the permeability of corrosive ions present in the acidic medium and thus acts as a barrier against the attack of corrosive environment. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
11.
Sin Helen Lee Yun Umeda Minoru Shironita Sayoko Rahim Afidah Abdul Saad Bahruddin 《Research on Chemical Intermediates》2017,43(3):1919-1934
Research on Chemical Intermediates - (2R,3R,4S,5R)-2-(6-amino-9H-purin-9-yl)-5-(hydroxymethyl)oxolane-3,4-diol (adenosine) is an identified component present in agarwood leaf extract. The corrosion... 相似文献
12.
S. Belkaid K. Tebbji A. Mansri A. Chetouani Belkheir Hammouti 《Research on Chemical Intermediates》2012,38(9):2309-2325
The influence of the addition of poly(4-vinylpyridine-hexadecyl bromide) P4VP-Alkyl 50?% newly synthesized on the corrosion of mild steel in molar hydrochloric acid has been investigated by weight-loss measurements combined with linear potential scan voltammetry (I?CE) and electrochemical impedance spectroscopy (EIS). The polymer reduces the corrosion rate and the inhibition efficiency (E?%) of P4VP-Alkyl 50?% increases with its concentration and attains 95?% at 300?mg/L. E?% obtained from cathodic Tafel plots, EIS, and gravimetric methods were in good agreement. The inhibitor was adsorbed on the iron surface according to the Langmuir adsorption isotherm model. Polarization measurements also show that the compound acts as a cathodic inhibitor. 相似文献
13.
A new corrosion inhibitor, namely acid extract of leaves of Hibiscus sabdariffa, has been synthesized, and its inhibiting action on the corrosion of mild steel in acidic bath (1.2 N HCl and 1.2 N H2SO4) has been investigated by corrosion-monitoring techniques. The results of the present study show that this compound has decent inhibiting property for mild steel corrosion in 1.2 N H2SO4 than 1.2 N HCl. Four sorption isotherms are tested for the data, namely Langmuir, Frumkin, Florry–Huggins, and Langmuir–Freundlich isotherms; of these the Langmuir isotherm fits the data well having correlation coefficient over 0.99 in both the acid environments. 相似文献
14.
《Green Chemistry Letters and Reviews》2013,6(4):307-314
Abstract Inhibitive and adsorption properties of albomycin as a green inhibitor for the corrosion of zinc in H2SO4 solutions were studied using weight loss and hydrogen evolution methods. The results obtained, indicate that albomycin is a good adsorption inhibitor for the corrosion of zinc in H2SO4 solution. The inhibition potentials of albomycin for the corrosion of zinc in H2SO4 solutions are attributed to the adsorption of the inhibitor on the surface of zinc and its inhibition efficiency increases with increase in the concentration of the inhibitor but decreases with increasing temperature. The range obtained for the values of activation energy and free energy of adsorption were within the limit expected for the mechanism of physical adsorption. Also, the adsorption of albomycin on zinc surface was spontaneous, exothermic, and supported the Langmuir adsorption model. Optimized structure of 2-[[2-[[5-[acetyl(hydroxy)amino]-2-[[5-[acetyl(hydroxy)amino]-2-[[5-[acetyl(hydroxy)amino]-2-aminopentanoyl]amino] pentanoyl] amino] pentanoyl]amino]-3-hydroxypropanoyl]amino]-3-[(2R,3S,4R,5R)-3,4-dihydroxy-5-(3-methyl-2,4-dioxopyrimidin-1-yl)thiolan-2-yl]-3-hydroxypropanoic acid; iron(3 + ) (albomycin) 相似文献
15.
M. Znini L. Majidi A. Bouyanzer J. Paolini J.-M. Desjobert J. Costa B. Hammouti 《Arabian Journal of Chemistry》2012,5(4):467-474
Essential oil of aerial parts of Salvia aucheri Boiss. var. mesatlantica was obtained by hydrodistillation and analyzed by GC and GC/MS. The oil was predominated by camphor (49.59%). The inhibitory effect of this essential oil was estimated on the corrosion of steel in 0.5 M H2SO4 using electrochemical polarization and weight loss measurements. The corrosion rate of steel is decreased in the presence of natural oil. The inhibition efficiency was found to increase with oil content to attain 86.12% at 2 g/L. Polarization curves revealed that the oil of S. aucheri mesatlantica acts as mixed type inhibitor with a strong predominance of anodic character. The temperature effect on the corrosion behavior of steel in 0.5 M H2SO4 without and with the inhibitor at 2 g/L was studied in the temperature range from 303 to 343 K, the associated activation energy have been determined. The adsorption of oil on the steel surface was found to obey Langmuir’s adsorption isotherm. 相似文献
16.
《Green Chemistry Letters and Reviews》2013,6(1):7-15
Abstract The corrosion inhibition and adsorption properties of Neem (Azadirachta indica – AZI) mature leaves extract as a green inhibitor of mild steel (MS) corrosion in nitric acid (HNO3) solutions have been studied using a gravimetric technique for experiments conducted at 30 and 60°C. The results disclose that the different concentrations of the AZI extract inhibit MS corrosion and that inhibition efficiency of the extract varies with concentration and temperature. For extract concentrations studied and ranging from 9.09 to 28.57 mg/L, the maximum inhibition efficiency was 80.5 and 80.07% both at 28.57 mg/L AZI at 30 and 60°C, respectively, in 2.0 N HNO3. The adsorption of the inhibitor on the MS surface was exothermic and consistent with the physical adsorption mechanism, best described by the Frumkin adsorption isotherm. 相似文献
17.
The adsorption and inhibition effect of xanthione (XION) on mild steel in 0.5 M H2SO4 at 303–333 K were studied using gravimetric and UV–visible spectrophotometric methods. The results obtained show that XION acts as an effective corrosion inhibitor for mild steel in sulphuric acid and inhibition efficiency reaches 98.0% at a very low inhibitor concentration of 10 μM. Inhibition efficiency was found to increase with increase in XION concentration but decreased with temperature suggesting physical adsorption mechanism. Arrhenius law and its transition equation lead to estimate the activation parameters of the corrosion process. XION inhibits the corrosion of mild steel effectively at moderate temperature and adsorbs according to the Langmuir isotherm. Thermodynamic parameters governing the adsorption process have been calculated and discussed. The UV–visible absorption spectra of the solution containing the inhibitor after the immersion of mild steel specimen indicate the formation of a XEN–Fe complex. Attempt to correlate the molecular structure to quantum chemical indices was made using density functional theory (DFT). 相似文献
18.
《印度化学会志》2022,99(11):100742
The heterocyclic system, namely 4-phenyl-decahydro-1H-1,5-benzodiazepin-2-one (POBZ) was inspected as a corrosion inhibitor of carbon steel (CS) in a 1 M HCl medium through electrochemical impedance spectroscopy (EIS), potentiodynamic polarization measurements (PDP), and scanning electron microscopy (SEM). The experimental data indicate that the inhibiting action augments with augmenting POBZ amount and reduces with augmenting temperature. The inhibiting action efficiency of 90.98% is obtained with 0.001 M at 303 K. The potentiodynamic polarization (PDP) results mentioned that the POBZ is of mixed type. The adsorption of POBZ on the CS followed Langmuir isotherm. SEM exams affirmed that the steel surface is smooth in presence of POBZ. In light of the calculations of density functional theory (DFT) and molecular dynamics simulation, the mechanism of POBZ inhibitory activity was addressed. 相似文献
19.
《印度化学会志》2021,98(11):100207
The inhibitive action of the aqueous extract of Ruellia tuberosa L (ART) on the corrosion of copper in 0.5 M HCl was investigated. The inhibition efficiency increased with the extract concentration, acid concentration, as well as increasing the temperature. The Polarization studies revealed that the ART act as a mixed-type inhibitor. Based on the analysis of electrochemical impedance spectroscopy, an equivalent circuit is suggested. The adsorption of the inhibitor ART on the copper surface obeyed the Langmuir adsorption isotherm. From the results of scanning electron microscopy, Fourier transform infrared spectroscopy, and energy-dispersive X-ray spectroscopy the adsorption of ART on the copper surface is confirmed. 相似文献
20.
Hachama Kamel Khadraoui Abdelkader Zouikri Mohamed Khodja Mohamed Khelifa Abdellah Echiker Khadidja Hammouti Belkheir 《Research on Chemical Intermediates》2016,42(2):987-996
Research on Chemical Intermediates - A new benzoxazin derivative, namely methyl 3-(2-oxo-2H-1,4-benzoxazin-3-yl) propanoate (1,4-MBXP), was synthesized under mild conditions from 2-aminophenols and... 相似文献