The Effect of Rotation and Temperature on the Inhibition Performance of Cashew (Anacardium Occidentale L.) Nut Shell Liquid on Co2 Corrosion of Carbon Steel

2008 ◽  
Vol 31 (2) ◽  
pp. 122-129
Author(s):  
J. Buchweishaija ◽  
L.L. Mkayala

A natural extract of cashew nut shells, Cashew Nut Shell Liquid (CNSL) was investigated as a corrosion inhibitor for carbon steel in 3% NaCl solutions saturated with CO2 gas using electrochemical techniques (i.e. potentiodynamic polarization and ac-impedance). The investigation was performed at different temperatures under static and dynamic conditions using a Rotating Disk Electrode (RDE). It was found that CNSL reduces the electrochemical processes taking place on carbon steel undergoing corrosion. The percentage inhibitorefficiency increases with increase in CNSL concentration and decreases with rise in temperature. Better performance at low CNSL concentration was registered under dynamic conditions and room temperatures. Thus CNSL is a potential corrosion inhibitor for carbon steel undergoing corrosion in CO2 medium.

2021 ◽  
Vol 12 (5) ◽  
pp. 7075-7091

The extract of Fucus spiralis (FS) was tested as a corrosion inhibitor of carbon steel in a 1M HCl medium. The anti-corrosion properties were analyzed by gravimetric and electrochemical techniques such as potentiodynamic polarization (PDP) and electrochemical impedance spectroscopy (EIS). The surface characterization of carbon steel submerged in the optimal solution was carried out using UV-Visible, UV-Vis-NIR, and Optical microscopy analyses. Electrochemical and gravimetric results demonstrated that inhibitory efficiencies increase with increasing inhibitor concentration and the efficiency reaches 87% at a concentration of 0.5 g/L. According to Tafel extrapolated polarisation measurements, the FS also worked as a mixed-type corrosion inhibitor and changed the mechanism of anodic reactions. EIS analysis showed that a depressed capacitive loop dominates the Nyquist plot of impedance and enhances the polarization resistance (Rp) to 161.9 Ω cm2 with a reduction of the double layer capacity (Cdl) of carbon steel to 61.8 μF/cm2. This protection is assured by an adsorption mechanism based on the isothermal Langmuir adsorption model, which positively affects the thermodynamic parameters. UV-Visible, UV-Vis-NIR analyses exhibited that inhibitor decreases the iron oxides like hematite, Magnetite, and Goethite, Maghemite, Lepidocrocite, δ-FeOOH of the metal surface and delays the dissolution of the bare metal of iron to the ferrous ions, notably that optical morphology showed that FS extract decreases the aggressivity of HCl.


2013 ◽  
Vol 773 ◽  
pp. 704-708
Author(s):  
Xin Wang ◽  
Zhen Fa Liu ◽  
Zhan Liu ◽  
Yun Juan Wu ◽  
Li Hui Zhang

A multifunctional corrosion inhibitor was prepared from polyaspartic acid (PASP), sodium gluconate,zinc sulfate,hydroxyphosphonoacetic acid (HPAA) and benzotriazole (BTA). The performance of corrosion inhibition was evaluated by rotary hanging-piece corrosion tests and steady polarization. The result showed that the corrosion inhibitor was an anodic inhibitor and had good corrosion inhibition performance both on A3 carbon steel and H62 copper in seawater. The corrosion inhibition rate of A3 carbon steel was 93.15% and the corrosion inhibition rate of H62 copper was 93.55% when the concentration of corrosion inhibitor was 150 mgL-1in seawater at 40°C.


Author(s):  
Salah Neghmouche Nacer ◽  
Touhami Lanez

We carried out a detailed study of the kinetics of oxidation of N'-ferrocenylmethyl-N'-phenylbenzohydrazide (FcX) to ferrocenium ion (FcX+) in aqueous and organic mediums. This study using cyclic (CV) and rotating disk electrode (RDE) voltammetry showed that the FcX/FcX+ redox couple is reversible. The N'-ferrocenylmethyl-N'-phenylbenzohydrazide and ferrocenium ion diffusion coefficients (D) were calculated from these results. In addition, the electron transfer rate constant and the exchange current density for the oxidation of ferrocene were determined. A comparison of the kinetic data obtained from the two electrochemical techniques appears to show that the data from the RDE experiments are more reliable because they are collected under strict mass transport control.


2001 ◽  
Vol 676 ◽  
Author(s):  
Mary Elizabeth Williams ◽  
Joseph T. Hupp

ABSTRACTWe have previously described the synthesis of a family of molecular ‘squares’ based on octahedral Re(I) coordination of difunctional bridging ligands. The size and chemical composition of the square cavity is highly tunable, and the inorganic cyclophanes are being actively studied in catalytic, separations, and sensing applications. Electrochemical techniques have been primary methods for characterization of the transport properties of thin films of the nanostructured materials. For example, cyclic voltammetry and rotating disk electrode voltammetry experiments have revealed size-selective permeation by redox probes, where the size cutoff is determined by the internal square dimensions. We have more recently begun to employ scanning electrochemical microscopy to spatially image micropatterned electrodes containing these thin film materials, simultaneously allowing us to obtain permeability data and topographical information. This paper describes data obtained by employing porphyrin-based molecular squares that feature chemically tailored cavities.


2021 ◽  
Author(s):  
Baiyi Chen ◽  
Guohe Xu ◽  
Luyao Wang ◽  
Chen Zhang ◽  
Congcong Li ◽  
...  

Abstract The acidic corrosion of carbon steel is a great concern, which has caused serious economic losses on a global scale. Therefore, the exploitation of corrosion inhibition strategy for carbon steel and an in-depth study on its mechanism are of vital importance. Here we have developed a mixed type corrosion inhibitor of PPy-CTS, which incorporated the good solubility and adsorption capacity of chitosan (CTS) into the excellent corrosion inhibition performance of polypyrrole (PPy) by in-situ polymerization of pyrrole on CTS. The corrosion inhibition performance of PPy-CTS composites as a potential corrosion inhibitor for Q235 carbon steel in 1 M HCl solution was investigated by electrochemical (potentiodynamic polarization curve and AC impedance spectroscopy) and surface morphological (scanning electron microscopy and water droplet contact angle) characterization. The results revealed that PPy-CTS with the optimal concentration of 250 ppm achieved the highest corrosion inhibition efficiency of 91.1%. Subsequently, the corrosion inhibition mechanism was furtherly studied. Gibbs free energy obtained from the Langmuir isotherm model suggested that the absorption of PPy-CTS corrosion inhibitor on Q235 steel in 1 M HCl solution belonged to a combined type of physisorption and chemisorption, which resulted in the formation of a physical barrier preventing the carbon steel from corrosion. In addition, the conductive polymer PPy of corrosion inhibitor possessed an oxide-film anodic protection for carbon steel. Ultimately, PPy-CTS effectively suppressed the corrosion reaction of carbon steel in harsh acidic environment through the synergistic effect of physical barrier and anodic protection.


2021 ◽  
pp. 1396-1403
Author(s):  
Rehab Majed Kubba ◽  
Nada Mohammed Al-Joborry

A newly derivative of oxazolidin-5- one namely [2-(2-biphenyl-4-yl-imidazo [1,2-a] pyridine-3-yl)-3-(4-nitro-phenyl)-oxazolidin-5-one (BIPNO5)] was examined as an corrosion inhibitor for carbon steel surface. Quantum mechanical method of Density Functional Theory (DFT) with (B3LYP (6-311++G (2d, 2p)) level of theory was used to calculate the minimize structure, physical properties and inhibition chemical parameters, in vacuum and two solvents (DMSO and H2O), all at equilibrium geometry. The results indicated that the new derivative could adsorb on the surface of carbon steel through the heteroatom, showing that the new inhibitor has good corrosion inhibition performance.


Sign in / Sign up

Export Citation Format

Share Document