Papers by Keyword: Corrosion Inhibitor

Abstract: In this research work, a new and green corrosion inhibitor based on new imidazole derivate (IMD) was introduced for carbon steel in 1 M HCl medium. Its inhibition properties were fully characterised by the gravimetric, electrochemical, surface and quantum chemical analyses. The experimental results confirmed that the inhibition efficiency of IMD was over 99% at 150 mg/L, forming a protective hydrophobic film on the metal surface, which maximally blocked the cathodic and anodic corrosive processes by adsorption. The electrochemical results suggested that the IMD is a mixed-type inhibitor. The adsorption behaviour of IMD was obeyed by Langmuir isotherms. The gravimetric results show that the inhibition efficiency depends on the change of concentration and temperature. The experimental tests were supported by the DFT (density functional theory) measurements, and a good relationship was found among these tests. The observed results of the surface analysis indicated that the metal surface was seriously improved with the presence of IMD.

Abstract: Corrosion is one of the serious problems in oil and gas industry. So far, many inhibitors have been used to control or reduce corrosion. Nowadays, nano-materials have been employed as inhibitors as well due to their excellent properties such as high surface area, excellent inhibition efficiency, low cost, and minimum toxicity. In the current work, nano-ferrite materials have been used as inhibitors to reduce the corrosion of carbon steel in oil environment (crude oil obtained from Iraqi Majnoon oil field). The anti-corrosion properties of the nickel and zinc ferrite on carbon steel in Iraqi oil media have been evaluated. The nano materials of nickel Ferrities (NiFe₂O₄) zinc Ferrities (ZnFe₂O₄) and Zn-Ni doped Ferities (Zn_0.6. Ni_0.4Fe₂O₄) were selected as additive ferrites. It has been found that nano-nickel and zinc ferrites could act as an effective corrosion inhibitor for the metal carbon steel. An average reduction of about 38% in the corrosion rate has been achieved when using Zn-Ni doped Ferities (Zn_0.6. Ni_0.4Fe₂O₄) with the crude oil as a corrosive environment.

Abstract: The behaviour of a corrosion inhibitor based on proplolis extract via an iron alloy immersed in an electrolyte containing ethylene glycol water in NaCl 0.1 M was evaluated by a stationary technique not destructive which is the technique of electrochemical impedance. The diameter of the Nyquist curves increases with the increase of the concentration of propolis extract and it reaches an optimum concentration at 1.25 g / L, the maximum surface coverage percent at this concentration is 71.98% .The activation parameters reveal that the inhibitor molecules on iron surface are absorbed by physisorption and a chimisorption and obey Langmuir isotherm adsorption. These results were supplemented by Scanning electron microscopy (SEM) and (EDX) spectrum of chemical composition. The metal solution interface is simulated as a physical model by using electrochemical impedance spectroscopy (EIS). Keywords: Iron Alloy, Propolis extract, ethylene glycol;, Lamgmuir isotherm, Electrochemical impedance Spectroscopy (EIS).

Abstract: Using inhibitors becomes an alternative way to reduce the level of corrosion. One type of the inhibitors proven effective is inorganic or chemical inhibitors. Regarding this, the purpose of this study is to determine the effectiveness of chemical inhibitors in reducing the level of corrosion. This study showed that the addition of natrium acetate and natrium was proven effective in reducing the corrosion, with the level of inhibitor efficiency of 75%. The result also showed that the inhibitors gave good performance to inhibit corrosion attack in natrium chloride acid medium, the form of corrosion that occurs in API 5L material is uniform corrosion.

Abstract: In this study, the dependence of corrosion inhibition and microbial effects of four N-hydroxymethylated amino acids, on their molecular and electronic structure is analyzed using density functional theory calculations. Quantum chemical parameters such as highest occupied molecular orbital energy (E_HOMO), lowest unoccupied molecular orbital energy (E_LUMO), energy gap (ΔE) were calculated at the B3LYP/6-311G++(d,p) basis set. Although no simple relationship between the inhibition performance and the calculated data could be discerned, the comparison of inactivation rate constants with energetic parameters suggested that microbial effects of the compounds can be explained in terms of their side chain disparities.

Abstract: The inhibition efficiency of Musa sapientum (banana) peel extracts at different concentrations and temperatures on mild steel corrosion in acidic solution of 1 M hydrochloric acid (HCl) were investigated by using weight loss method. The banana peel extract concentrations were tested from 300 to 500 ppm at temperature range between 25°C to 60°C. The performance of banana peel extract as an inhibitor was found compatible in the tested solution. The corrosion rates, which were calculated from the weight loss data, showed that the inhibition efficiency of the extract increased from 86.9% to 89.0% as the concentration of banana peel extract increased from 300 ppm to 500 ppm. It was also observed that the inhibition efficiency decreased as the temperature was increased from 25°C to 60°C. Characterization of the peel extract by using gas chromatography-mass spectrometry (GC-MS) has detected the presence of bioactive compounds which are responsible for the corrosion inhibition and adsorption properties on mild steel surface. Eleven major compounds have been identified as having corrosion inhibition properties. FTIR analysis confirmed the presence of functional groups of alcohols, alkanes, carbonyls, aromatics, ethers, and esters that can prevent corrosion by adsorption on steel surface.

Abstract: Corrosion inhibition characteristics of artesunate and rutin on carbon steel in water has been studied using density functional theory (DFT). Quantum chemical parameters such as highest occupied molecular orbital energy (E_HOMO), lowest unoccupied molecular orbital energy (E_LUMO), energy gap (ΔE), and global reactivity properties have been calculated at the B3LYP/6-311G(d,p) basis set. The results of theoretical calculations confirm the experimental findings on the superiority of rutin to protect the corrosion of steel in aqueous media compared to artesunate.

Abstract: The efficiency of benzalkonium chloride (BKC) to inhibit the corrosion of carbon steel API 5L in 1 M HCl has been studied by potentiodynamic polarization method and X-ray photoelectron spectroscopy (XPS). Potentiodynamic polarization indicated that BKC is able to retard the corrosion reaction of carbon steel and its corrosion rate decreased with the increasing of BKC concentration up to optimum concentration 7.5 mM. Adsorption and thermodynamic studies indicated that BKC molecules were capable of adsorbing onto carbon steel surface by following Langmuir adsorption isotherm model and their Gibbs free energy obtained at 25, 40, 55 and 70°C were -29.15, -31.67, -37.46 and -35.76 kJ/mol, respectively. Thermodynamically point of view shown that adsorption mechanism of BKC onto carbon steel occurred via both physisorption and chemisorption process. While, adsorption mechanism establish by XPS analysis indicated that BKC was dominantly inhibit the carbon steel via physisorption process. As a conclusion, both potentiodynamic polarization method and XPS suggested that BKC is able to adsorb onto carbon steel and protect the surface from actively react with HCl.

Abstract: Corrosion can lead to failures in plant infrastructure and machines which are usually costly to repair, contaminating the product and causes environmental damage. Green inhibitor is a corrosion inhibitor which normally comes from the extract of plants and can inhibit corrosion by using chemisorption and/or physisorption mechanism on the metal surface or reacting with metal ions and forming a barrier-type precipitate on its surface. This paper discusses the corrosion inhibition of low carbon steel by addition of palm oil and corn oil as green inhibitors. We also compared the effect of these inhibitors in water and salt water environment. The corrosion behaviour of the low carbon steel was determined by immersion and electrochemical tests. The immersion test was carried out by immersing the samples in distilled water and 3.5% NaCl solution with and without the inhibitors for 1,2,4,6 and 8 weeks. The concentration of the inhibitors used was 100 g/L for both corn oil and palm oil. Scanning Electron Microscopy, Energy Dispersive Spectroscopy and X-Ray diffractometer were used to analyse the results. Immersion test results show that there is a slight weight gain for low carbon steel immersed in the presence of inhibitors suggesting that there is a thin protective layer formed which act as a barrier towards corrosion. Corn oil inhibitor in distilled water shows the highest inhibition efficiency. Its inhibition efficiency is 93.9%, which is slightly higher than palm oil (91.5%) in similar environment.

Abstract: Red cabbage extract has been investigated in this work whether it would perform as a green corrosion inhibitor for API 5L grade X60 steel in 3.5% NaCl environment. Based on the FTIR and LC-MS analysis the active compounds of corrosion inibitor were hydroxyl, carbonyl and cyanidin. The Tafel polarization test results showed that red cabbage extract performed as a mixed corrosion inhibitor and the Electrochemical Impedance Spectroscopy test results showed that the impedance, polarization resistance and capacitive resistance of steel surface increased with the addition of red cabbage corrosion inhibitor. Based on evaluation of the testing results red extract red cabbage performed significant corrosion inhibition effect. The inhibitor efficiency increases with increased corrosion inhibitor concentration and the optimum inhibitor percent efficiency achieved 81%. The adsorption mechanism of red cabbage corrosion inhibitor can be considered as a Langmuir Isotherm