The mechanism for corrosion protective film formation on iron and nickel in acid solutions with organo-antimony compounds

1992 ◽  
Vol 33 (8) ◽  
pp. 1253-1265 ◽  
Author(s):  
Norimichi Saito ◽  
Hiroshi Nishihara ◽  
Kunitsugu Aramaki
Keyword(s):  
Film Formation ◽  
Protective Film ◽  
Acid Solutions

scholarly journals Spilanthes acmella Leaves Extract for Corrosion Inhibition in Acid Medium

Coatings ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 106
Author(s):  
Akbar Ali Samsath Begum ◽  
Raja Mohamed Abdul Vahith ◽  
Vijay Kotra ◽  
Mohammed Rafi Shaik ◽  
Abdelatty Abdelgawad ◽  
...  
Keyword(s):  
Mild Steel ◽  
Corrosion Inhibition ◽  
Active Sites ◽  
Inhibition Efficiency ◽  
Electrochemical Impedance ◽  
Film Formation ◽  
Protective Film ◽  
Surface Protection ◽  
Tafel Polarization ◽  
Spilanthes Acmella

In the present study, the corrosion inhibition effect of Spilanthes acmella aqueous leaves extract (SA-LE) on mild steel was investigated in 1.0 M HCl solution at different temperature using weight loss, Tafel polarization, linear polarization resistance (LPR), and electrochemical impedance (EIS) measurements. Adsorption of inhibitor on the surface of the mild steel obeyed both Langmuir and Temkin adsorption isotherms. The thermodynamic and kinetic parameters were also calculated to determine the mechanism of corrosion inhibition. The inhibition efficiency was found to increase with an increase in the inhibitor concentration i.e., Spilanthes acmella aqueous leaves extract, however, the inhibition efficiency decreased with an increase in the temperature. The phytochemical constituents with functional groups including electronegative hetero atoms such as N, O, and S in the extract adsorbed on the metal surface are found responsible for the effective performance of the inhibitor, which was confirmed by Fourier-transform infrared spectroscopy (FT-IR) and ultraviolet–visible spectroscopic (UV-Vis) studies. Protective film formation against corrosion was confirmed by scanning electron microscopy (SEM), atomic force microscopy (AFM), and contact angle studies. The result shows that the leaves extract acts as corrosion inhibitor and is able to promote surface protection by blocking active sites on the metal.

scholarly journals Comparison Between the Action of Nano-Oxides and Conventional EP Additives in Boundary Lubrication

Lubricants ◽  
2020 ◽  
Vol 8 (5) ◽  
pp. 54
Author(s):  
Valdicleide Silva Mello ◽  
Marinalva Ferreira Trajano ◽  
Ana Emilia Diniz Silva Guedes ◽  
Salete Martins Alves
Keyword(s):  
Friction Coefficient ◽  
Boundary Lubrication ◽  
Friction And Wear ◽  
Film Formation ◽  
Environmental Issues ◽  
Protective Film ◽  
Extreme Pressure ◽  
Extreme Pressure Additives ◽  
Environmental Requirements ◽  
Lubrication Conditions

Additives are essential in lubricant development, improving their performance by the formation of a protective film, thus reducing friction and wear. Some such additives are extreme pressure additives. However, due to environmental issues, their use has been questioned because their composition includes sulfur, chlorine, and phosphorus. Nanoparticles have been demonstrated to be a suitable substitute for those additives. This paper aims to make a comparison of the tribological performance of conventional EP additives and oxides nanoparticles (copper and zinc) under boundary lubrication conditions. The additives (nanoparticles, ZDDP, and sulfur) were added to mineral and synthetic oils. The lubricant tribological properties were analyzed in the tribometer HFRR (high frequency reciprocating rig), and during the test, the friction coefficient and percentual of film formation were measured. The wear was analyzed by scanning electron microscopy. The results showed that the conventional EP additives have a good performance owing to their anti-wear and small friction coefficient in both lubricant bases. The oxides nanoparticles, when used as additives, can reduce the friction more effectively than conventional additives, and displayed similar behavior to the extreme pressure additives. Thus, the oxide nanoparticles are more environmentally suitable, and they can replace EP additives adapting the lubricant to current environmental requirements.

Cooling Water Inhibitor Performance

CORROSION ◽  
1960 ◽  
Vol 16 (10) ◽  
pp. 473t-478t ◽  
Author(s):  
P. R. PUCKORIUS ◽  
W. J. RYZNER
Keyword(s):  
Corrosion Inhibitors ◽  
Film Formation ◽  
Cooling Water ◽  
Water Systems ◽  
Continuous Treatment ◽  
Protective Film ◽  
Low Level ◽  
Start Up ◽  
Actual Field ◽  
High Level

Abstract Corrosion inhibitors in open recirculating cooling water systems require rapid and complete film formation for maximum effectiveness. The protective film is established on clean surfaces by initial treatment with inhibitor at high dosage levels. Protection then can be maintained by continuous treatment at substantially lower levels. If operational difficulties should cause loss of the protective film, low level treatment after the film has been lost may result in severely increased corrosion and deposition. Laboratory corrosion, deposition and consumption studies with polyphosphate-based and chromate-based inhibitors illustrate the advantages of high level start-up and low level maintenance treatments. These data are confirmed by actual field experiences. 5.8.1

scholarly journals Protective Film Formation on AA2024-T3 Aluminum Alloy by Leaching of Lithium Carbonate from an Organic Coating

2015 ◽  
Vol 163 (3) ◽  
pp. C45-C53 ◽  
Author(s):  
Yanwen Liu ◽  
Peter Visser ◽  
Xiaorong Zhou ◽  
Stuart B. Lyon ◽  
Teruo Hashimoto ◽  
...  
Keyword(s):  
Aluminum Alloy ◽  
Film Formation ◽  
Lithium Carbonate ◽  
Organic Coating ◽  
Protective Film

The Effect of Solution Ph and Ion Concentrations on Leaching of Silicate Glass

1982 ◽  
Vol 15 ◽  
Author(s):  
Bruce C. Bunker ◽  
George W. Arnold
Keyword(s):  
Film Formation ◽  
Protective Film ◽  
Selective Leaching ◽  
Exchange Reactions ◽  
Solution Ph ◽  
Reaction Type ◽  
Glass Dissolution ◽  
Gel Layer ◽  
Complex Process ◽  
Second Category

For complex glasses such as simulated nuclear wastes, glass dissolution is a complex process, involving selective leaching of cations, reprecipitation reactions, and protective film formation. In order to begin to understand this complex behavior, each of the above phenomena is being studied, one reaction at a time, on simple alkali silicate glasses under controlled environmental conditions. To date, two types of reactions have been investigated. The first reaction type is the selective leaching of cations from the glass, resulting in the formation of a hydrated “gel” layer on the glass surface. The second reaction type is the reaction of ionic or colloidal species in solution with this gel layer. Reactions in the second category include ion exchange reactions and sorption reactions which can result in protective film formation. Studies of these simple reactions have led to the development of new leaching models and to observations which begin to explain the behavior of complex glasses, and predict how glass dissolution should change as a function of the chemical environment.

scholarly journals Aqueous Dried Extract of Skytanthus acutus Meyen as Corrosion Inhibitor of Carbon Steel in Neutral Chloride Solutions

Metals ◽  
2021 ◽  
Vol 11 (12) ◽  
pp. 1992
Author(s):  
Luis Cáceres ◽  
Yohana Frez ◽  
Felipe Galleguillos ◽  
Alvaro Soliz ◽  
Benito Gómez-Silva ◽  
...  
Keyword(s):  
Carbon Steel ◽  
Inhibitory Activity ◽  
Electrochemical Impedance ◽  
Film Formation ◽  
Quinic Acid ◽  
Iron Complex ◽  
Water Soluble ◽  
Protective Film ◽  
Native Plant ◽  
Iron Cycling

The implementation of corrosion engineering control methods and techniques is crucial to extend the life of urban and industrial infrastructure assets and industrial equipment affected by natural corrosion. Then, the search of stable and environmentally friendly corrosion inhibitors is an important pending task. Here, we provide experimental evidence on the corrosion inhibitory activity of aqueous extracts of Skytanthus acutus Meyen leaf, a native plant from the Atacama Desert in northern Chile. Skytanthus extracts as a powder should be prepared at 55 °C to avoid thermal decomposition and loss of corrosion inhibitory activity. Corrosion of carbon steel AISI1020 immersed in 0.5 M NaCl was evaluated in the presence of different doses of Skytanthus extract by complementary and simultaneous linear polarization, electrochemical impedance spectroscopy, and weight-loss technique under high hydrodynamic conditions. Mixed Potential Theory was applied to confirm the electrochemical activity of the extract inhibitory capabilities. The Skytanthus extracts reached a 90% corrosion inhibitory efficiency when tested at 100 to 1200 ppm in a time span of 48 h, through an electrochemical interaction between the extract inhibitor component and the carbon steel surface. The corrosion inhibition activity observed in Skytanthus dry extracts involves a protective film formation by a mechanism that includes an iron dissolution at the expense of either oxygen reduction and/or hydrogen evolution, followed by a ferrous-ferric iron cycling, the formation of an iron complex and adsorption to the metal surface, and, finally, desorption or degradation of the protecting film. The water-soluble plant extract was subjected to HPLC-MS analyses that rendered 14 major signals, with quinic acid, protocatechuic acid, chlorogenic acid isomers, vanillic acid hexoside, and patuletin 3-methoxy-7-glucoside as the most abundant components. Then, we propose that a phenolic derivative is responsible for the corrosion inhibitory activity found in Skytanthus extracts.

scholarly journals Discoloration Resistance of Electrolytic Copper Foil Following 1,2,3-Benzotriazole Surface Treatment with Sodium Molybdate

Coatings ◽  
2018 ◽  
Vol 8 (12) ◽  
pp. 427 ◽  
Author(s):  
Dong-Jun Shin ◽  
Yu-Kyoung Kim ◽  
Jeong-Mo Yoon ◽  
Il-Song Park
Keyword(s):  
Surface Treatment ◽  
Photoelectron Spectroscopy ◽  
Copper Foil ◽  
Deposition Time ◽  
Film Formation ◽  
Electrochemical Corrosion ◽  
Sodium Molybdate ◽  
Surface Characteristics ◽  
Protective Film ◽  
Electrolytic Copper

The copper which an important component in the electronics industry, can suffer from discoloration and corrosion. The electrolytic copper foil was treated by 1,2,3-benzo-triazole (BTA) for an environmentally friendly non-chromate surface treatment. It was designed to prevent discoloration and improve corrosion resistance, consisted of BTA and inorganic sodium molybdate (Na2MoO4). Also the ratio of the constituent compounds and the deposition time were varied. Electrochemical corrosion of the Cu-BTA was evaluated using potentiodynamic polarization. Discoloration was analyzed after humidity and heat resistance conditioning. Surface characteristics were evaluated using scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Increasing corrosion potential and decreasing current density were observed with increasing Na2MoO4 content. A denser protective coating formed as the deposition time increased. Although chromate treatment under severe humidity (80% humidity, 80 °C, 100 h) provided the highest humidity resistance, surface treatment with Na2MoO4 had better heat discoloration inhibition under severe heat-resistant conditions (180 °C, 10 min). When BTA reacts with Cu to form the Cu-BTA-type insoluble protective film, Na2MoO4 accelerates the film formation without being itself adsorbed onto the film. Therefore, the addition of Na2MoO4 increased anticorrosive efficiency through direct/indirect action.

Sign in / Sign up

Export Citation Format

Share Document