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Cashew nut shell liquid as an alternative corrosion inhibitor for carbon steels.
JYN Philip, J Buchweishaija, LL Mkayula
Tanzania Journal of Science , 2001,
Abstract: Cashew Nut Shell Liquid (CNSL) has been tested as a corrosion inhibitor for carbon steel in 3% aqueous NaCl solution (pH 6) saturated with carbon dioxide gas at 30°C under static conditions using ac-impedance and potentiodynamic polarisation techniques. It was found that CNSL reduces the extent of the electrochemical processes taking place on carbon steel undergoing corrosion. The corrosion rate of the carbon steel was reduced by over 92 % when only 300 ppm of CNSL was applied. This indicates that CNSL is a potential corrosion inhibitor for carbon steels in CO2 environment. Tanzania Journal of Science Volume 27 (2001), pp. 9-19
The Synthesis of Imidazoline Derivative Compounds as Corrosion Inhibitor towards Carbon Steel in 1% NaCl Solution  [PDF]
Deana Wahyuningrum,Sadijah Achmad,Yana Maolana Syah,Buchari
ITB Journal of Science , 2008,
Abstract: Oleic imidazoline is one of the nitrogen containing heterocyclic compounds that has been widely used as commercial corrosion inhibitor, especially in minimizing the carbon dioxide induced corrosion process in oilfield mining. In this present work, some imidazoline derivative compounds have been synthesized utilizing both conventional and microwave assisted organic synthesis (MAOS) methods, in order to determine their corrosion inhibition properties on carbon steel surface. The MAOS method is more effective in synthesizing these compounds than the conventional method regarding to the higher chemical yields of products (91% to 94%) and the shorter reaction times (7 to 10 minutes). The characterization of corrosion inhibition activities of the synthesized products towards carbon steel in 1% NaCl solution was determined by the Tafel plot method. The corrosion inhibition activities of compound 1b ((Z)-2-(2-(heptadec-8-enyl)-4,5-dihydroimidazol-1-yl)ethanamine), 2b ((Z)-2-(2-(heptadec-8-enyl)-4,5-dihydroimidazol-1-yl)ethanol) and 3b (2-(2-heptadecyl-4,5-dihydroimidazol-1-yl)ethanamine) at 8 ppm concentration in 1% NaCl solution are, respectively, 32.18%, 39.59% and 12.73%. The heptadec-8-enyl and hydroxyethyl substituents at C(2) and N(1) position of imidazoline ring, respectively, gave the most effective corrosion inhibition activity towards carbon steel compared to the presence of other substituents. The increase in concentrations of compound 1b, 2b and 3b in 1% NaCl solution tends to improve their corrosion inhibition activities. Based on the analysis of the free Gibbs adsorption energy (DG0ads) values of compound 1b, 2b and 3b (-32.97, -34.34 and -31.27 kJ/mol, respectively), these compounds have the potential to interact with carbon steel through semi-physiosorption or semi-chemisorption.
Regeneration of Nickel-Molybdenum Catalysts DN-3531 and Criterion 514 Used in Kerosene and Gas Oil Hydrotreating by Supercritical Carbon Dioxide Extraction  [PDF]
Ameer Abed Jaddoa, Timur R. Bilalov, Farid M. Gumerov, Farizan R. Gabitov, B. Le Neindre
International Journal of Analytical Mass Spectrometry and Chromatography (IJAMSC) , 2015, DOI: 10.4236/ijamsc.2015.33005
Abstract: Results of research of supercritical fluid CO2-regeneration process of Nickel-Molybdenum Catalysts DN-3531 and Criterion 514 are given. Regeneration was carried out with the use of pure supercritical carbon dioxide and mixture of supercritical carbon dioxide and various polar cosolvents. Regeneration process is carried out along isotherms, in the temperature range of 323 - 383 K, at pressures of P = 20 MPa and 30 MPa. Results of surface assessment of the catalyst samples regenerated show high effectiveness of suggested method.
Guar Gum as Corrosion Inhibitor for Carbon Steel in Sulfuric Acid Solutions
Abdallah,M.;
Portugaliae Electrochimica Acta , 2004,
Abstract: guar gum was tested as corrosion inhibitor for carbon steel in 1 m h2so4 solution using weight loss and tafel polarization techniques. the results showed that the inhibition efficiency increases with the increasing of the guar gum concentration, which act as an inhibitor of the mixed type. the inhibition action of guar gum was discussed in terms of its horizontal adsorption on the metal surface. the adsorption follows langmuir adsorption isotherm. the effect of the presence of chloride ion in pitting corrosion was analyzed by the potentiodynamic anodic polarization technique. the pitting corrosion potential changes with the concentration of cl- ion according to a sigmoid s-shaped curve. this behaviour was explained on the basis of the formation of passivatable, active and continuously propagated pits.
Guar Gum as Corrosion Inhibitor for Carbon Steel in Sulfuric Acid Solutions  [cached]
M. Abdallah
Portugaliae Electrochimica Acta , 2004,
Abstract: Guar gum was tested as corrosion inhibitor for carbon steel in 1 M H2SO4 solution using weight loss and Tafel polarization techniques. The results showed that the inhibition efficiency increases with the increasing of the guar gum concentration, which act as an inhibitor of the mixed type. The inhibition action of guar gum was discussed in terms of its horizontal adsorption on the metal surface. The adsorption follows Langmuir adsorption isotherm. The effect of the presence of chloride ion in pitting corrosion was analyzed by the potentiodynamic anodic polarization technique. The pitting corrosion potential changes with the concentration of Cl- ion according to a sigmoid S-shaped curve. This behaviour was explained on the basis of the formation of passivatable, active and continuously propagated pits.
UAE Neem Extract as a Corrosion Inhibitor for Carbon Steel in HCl Solution  [PDF]
Ayssar Nahlé,Ideisan Abu-Abdoun,Ibrahim Abdel-Rahman,Maysoon Al-Khayat
International Journal of Corrosion , 2010, DOI: 10.1155/2010/460154
Abstract: The effect of aqueous extract of UAE Neem (Azadirachta Indica) on the corrosion inhibition of carbon steel in 1.0?M HCl solution was investigated electrochemically, and by weight-loss experiments at temperatures ranging from 303 to 343?K. The percentage inhibition increased with the increase of the concentration of the inhibitor. At a concentration of 2.0?g/L, the percentage inhibition reached about 87% at room temperature and 80% at 303?K. The percentage inhibition decreased with the increase of temperature. The thermodynamic parameters for the adsorption of this inhibitor on the metal surface were calculated using the Temkin adsorption isotherm. The aqueous Neem leaves extract was found to be an excellent potential corrosion inhibitor because of the high content of tannin content as well as the presence of a series of complex triterpene glycosides. 1. Introduction The corrosion of metals in many industries, constructions, installations, and civil services such as electricity, water, and sewage supplies is a serious problem. In order to prevent or minimize corrosion, inhibitors are usually used especially in flow cooling systems. Organic, inorganic, or a mixture of both inhibitors can inhibit corrosion by either chemisorption on the metal surface or reacting with metal ions and forming a barrier-type precipitate on its surface [1]. Because of the toxic nature and/or high cost of some chemicals currently in use as inhibitors, it is necessary to develop environmentally acceptable and inexpensive ones. Natural products can be considered as a good source for this purpose. The aqueous extracts from different parts of some plants such as Henna, Lawsonia inermis [1], Rosmarinous officinalis L. [2], Carica papaya [3], cordia latifolia and curcumin [4], date palm, phoenix dactylifera, henna, lawsonia inermis, corn, Zea mays [5], and Nypa Fruticans Wurmb [6] have been found to be good corrosion inhibitors for many metals and alloys. Recently, an excellent review about “natural products as corrosion inhibitors for metals in corrosive media” has been published [7]. No studies have been reported on the aqueous extract of Neem leaves planted in UAE, Azadirachta indica, as corrosion inhibitor used in our present work, in terms of studying both the electrochemical effect and the temperature effect on the corrosion inhibition of carbon steel in 1.0?M HCl solution. Carbon steel was chosen in our studies since high temperature aggressive acids are widely used in industries in connection to carbon and low alloy steels. The aim of this work is to study, using
Synthesis and Characterization of Benzothiazol Derivative as a Corrosion Inhibitor for Carbon Steel in Seawater  [PDF]
Abdulkareem Mohammed Ali Al-Sammarraie, Khulood Abid Al-Saade, Mohammed H. A. Al-Amery
Materials Sciences and Applications (MSA) , 2015, DOI: 10.4236/msa.2015.67070
Abstract: 2(Benzo[d]thiazol-2-ylamino)-2-(2-hydroxy-phenyl) acetonitrile derivative was prepared and characterized using thin liquid chromatography, FTIR, 1H NMR and 13C NMR. The corrosion protectiveness, kinetics, and thermodynamics of the prepared derivative as inhibitor in artificial sea water/carbon steel (CK45) system were studied. Three concentrations of the prepared inhibitor were examined, namely, 10, 100, and 1000 ppm; protection efficiencies of 23% to 73% were recorded. It was found that the experimental data obtained from polarization reading could be fitted by Langmuir isotherm and Frumkin’s isotherm; the best fit adsorption isotherm was the Frumkin adsorption isotherm. The small negative value of ΔGads indicates the spontaneity of a physical adsorption process and the stability of the adsorbed layer on the carbon steel surface. Analysis of the temperature dependence of inhibition efficiency as well as comparison of corrosion activation in absence and in presence of the inhibitors gives some insight into the possible inhibition mechanism.
CORROSION INHIBITOR FOR PICKLING OF CARBON STEEL IN HYDROCHLORIC ACID
适用于带钢酸洗的盐酸缓蚀剂

SUN Lei,ZHANG Min-qing,
孙磊
,张敏卿

腐蚀科学与防护技术 , 2007,
Abstract: The efficiency for suppresing acid fogging and corrosion inhibition of iron during pickling process of iron in hydrochloric acid is studied by means of addition of agents such as urotropine, Dye Leveller AN, sodium dodecyl sulfate, OP-10 and so on. The influence of temperature and concentration of corrosion inhibitor in the pickling bath were studied. It is focused on influence of inhibitor on recovery of waste hydrochloric acid by roasting. In practical application, the efficiency of corrosion inhibition reaches ninety percent and the influences of inhibitor on recovery of waste hydrochloric acid by roasting is very little.
A REVIEW ON CARBON DIOXIDE CORROSION OF STEEL IN OILFIELD EXPLOITATION
油气开发中的CO2腐蚀

WANG Fengping,LI Xiaogang,DU Yuanlong,
王凤平
,李晓刚,杜元龙,

腐蚀科学与防护技术 , 2002,
Abstract: The paper reviews the features,the mechanism and the forecast model of CO 2 corrosion in oil and gas exploitation.Generally,CO 2 corrosion is a typical localized corrosion,which causes a serious economy loss.The corrosion product(FeCO 3) or scale (CaCO 3) deposited on different areas of steel.With different coverage,different areas form some corrosion couples with self-catalytic feature.It is the corrosion couples that result in CO 2 localized corrosion.It is of great significance to establish a forecast model of CO 2 corrosion for protection of tubes and design of anti-corrosion in oilfield.
Fennel (Foeniculum Vulgare) Essential Oil as Green Corrosion Inhibitor of Carbon Steel in Hydrochloric Acid Solution
Lahhit,N.; Bouyanzer,A.; Desjobert,J.-M.; Hammouti,B.; Salghi,R.; Costa,J.; Jama,C.; Bentiss,F.; Majidi,L.;
Portugaliae Electrochimica Acta , 2011,
Abstract: essential oil from fennel (foeniculum vulgare) (fm) was tested as corrosion inhibitor of carbon steel in 1 m hcl using electrochemical impedance spectroscopy (eis), tafel polarisation methods and weight loss measurements. the results show that the increase of the charge-transfer resistance (rct) with the oil concentration supports the molecules of oil adsorption on the metallic surface. the polarization plots reveal that the addition of natural oil shifts the cathodic and anodic branches towards lower currents. such shifts indicate that fm oil acts as a mixed-type inhibitor. the global rate of corrosion estimated by weight loss measurements confirms the above results. the inhibition efficiency attains a maximum of 76 % at 3 ml/l, but decreases with the rise of temperature. the analysis of fm oil, obtained by hydro-distillation, using gas chromatography (gc) and gas chromatography/mass spectrometry (gc/ms) showed that the major components were limonene (20.8 %) and β-pinene (17.8%). the adsorption of fm on the steel surface has been discussed according to the chemical composition of the oil, giving an explanation to the obtained results.
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