Utilization of Natural Extracts as Corrosion Inhibitors in the Seawater Environment

Infrastructures in coastal area are mostly made of metal which is susceptible to corrosion due to direct contact with the seawater. The Seawater greatly affects the corrosion rate of metals because it contains chloride ions which can penetrate metal surface. The process of corrosion can be inhibited or slowed by decreasing the corrosion rate in one way, namely the addition of corrosion inhibitors derived from natural materials containing tannin compounds. This study proposed organic corrosion inhibitors which were derived from natural material extracts (coffee leaves and catappa leaves), the effect of time variations on the efficiency of organic inhibitors was investigated, and the efficiency of each inhibitor organic was compared. The corrosion rate with and without inhibitors was analysed by using the method of weight loss. The results showed that the corrosion rate can be reduced by adding the natural ingredients extract. The addition of 2% concentration coffee leaves extract resulted in the lowest corrosion rate with the addition of 0.00226 mmpy. The addition of catappa leaves extract concentration as much as 2% yield the lowest corrosion rate with the addition of 0.0012 mmpy. The highest efficiency of inhibition system was obtained by using 2% catappa leaves extract at 14 days soaking time at 69.23%, and the lowest by using 1% coffee leaves extract.

NEW CORROSION INHIBITORS BASED ON AMINES AND AMIDES

In this work, new inhibitors of metal corrosion in sulfuric acid media are investigated depending on the duration of the process, inhibitor concentration and temperature. The main parameters of the synthesis of new corrosion inhibitors for metals of grade St.3 and St.12 with the use of amine and amide-containing organic substances have been determined, and methods for preparing these inhibitors have been described. The physicochemical properties of amine and amide containing organic inhibitors of corrosion and salt deposition in acidic process media have been studied.

Corrosion inhibition of locally de-passivated surfaces by DFT study of 2-mercaptobenzothiazole on copper

Investigating the interaction of organic inhibitors with metal and alloy surfaces is crucial for an atomic-scale understanding of their protection efficiency, particularly on the initiation of localized corrosion by pitting. Quantum chemical DFT calculations were performed to optimize the constructed model of a depassivated copper surface and to study the adsorption of 2-mercaptobenzothiazole (MBT), on different zones exposed by local depassivation. Reactive sites exist at the metal surface, at the oxide surface, as well as on the oxide edges and oxide walls. The surface-reactive sites are the unsaturated and saturated copper atoms and singly and doubly unsaturated oxygen atoms of the oxide, and the copper atoms of the metal. The sulfur (Sexo and Sendo) and nitrogen (N or NH) atoms are the reactive sites in the molecules. MBT can covalently bond to the oxide surface as well as to the oxide edges, oxide walls, and metal surface exposed by depassivation. For the thione species, local adsorption strength decreases as oxide edges > oxide surface > metal surface > oxide walls, suggesting that MBT heals the low coordinated sites. For the thiolate species, adsorption strength is similar on the different area, except the oxide walls. The results show the ability of the inhibitor to interact on different zones of a locally depassivated surface and to form a strongly adsorbed organic film, which can block the initiation of localized corrosion by enhancing the interfacial barrier properties, including in the local surface areas incompletely passivated or locally damaged by depassivation.

Analysis of Pyridine, Picoline and Lutidine’s Adsorption Behavior on The Al (111)-lattice

The reactivity and adsorption behavior of five organic inhibitors of pyridine and its derivatives of 2-picoline, 3-picoline, 4-picoline, and 2,4-lutidine at the Al(111) lattice in hydrochloric acid was studied by the principle of the HF and B3LYP level using the 6-31G and LANL2DZ basis sets from the program package gaussian 03. The compound was adsorbed on the metal lattice based on the calculated results, mainly in their protonated forms. In the Al (111)-lattice, the charge is transferred to the inhibitor, and the organic inhibitor is adsorbed at the Al (111)-lattice in an inclined state. The quantum chemical calculations of molecular reactivity show that the frontier orbitals of the four additives are distributed around the nitrogen atom of the pyridine ring, the aluminum atom of Al (111)-lattice, and active electrophilic centers are located on the nitrogen atoms of the pyridine ring. All five molecules were adsorbed with the chemical adsorption on the Al (111)-lattice, and the order of adsorption was 2-picoline>2, 4-lutidine> 4-picoline> 3-picoline> pyridine. The N atoms of four derivatives form N-Al bonds with the Al atoms of the Al (111)-lattice, which makes derivatives stably adsorb on the Al lattice.

Green Organic Inhibitors for Corrosion Protection

Plants are a rich source of different varied organic compounds. Due to the important applications of naturally occurring chemicals their derivatives are also pursued for modifying and potentiating the activities of natural products. Metallic corrosion is a natural process resulting in heavy losses in various fields. Non hazardous and non toxic corrosion inhibitors gained significance due to the environmental regularities and guidelines issued in the course of saving the pristine nature of environment and to maintain the sustainability of our earth. Green corrosion inhibitors play a potential role for the above said cause. Recent research contributions on green corrosion inhibitors from the active researchers in the concerned expertise are presented briefly here to give an idea about the current research activity across the world.

Synthesis, Characterization of New Polytriazole Derivatives from Polyacryloyl chloride and Theoretical with Corrosion Inhibitor Study for Stainless steel in acidic medium

The purpose of the study is to synthesize and characterize a new polytriazole derivative from polyacryloyl chloried, first reaction of polyacryloyl chloride with hydrazine hydrate in the presence of DMF as a solvent to obtained acid hydrazide (1) than reacted with different amide to give poly 1,2,4-triazole derivatives(1a-1c). Newly synthesized compounds were characterized by spectral methods [13C-NMR, 1H-NMR, and FTIR] and calculated some of its physical properties. Also, we worked theoretical study involving calculated the geometric configurations, total energy, dipole moment etc..,. In addition, the inhibition effect of the synthesized compounds (1a-1c) on corrosion of stainless steel in 1M HCl were studied by method of weight loss. The results of weight loss measurements showed that corrosion inhibition efficiency by increasing the concentration of organic inhibitors for stainless steel in 1M HCl solution at 30oC.

A Review on Plants and Biomass Wastes as Organic Green Corrosion Inhibitors for Mild Steel in Acidic Environment

Acid corrosion is a problem pertaining to corrosion that involves an acid solution. It is important to treat metal to preserve its integrity. Thus, acids are utilized to clean and treat metal surfaces. In return, this may lead to over-etching and metal degradation. Corrosion inhibitors were introduced as a solution for the issue. However, there are some problems associated with the usage of conventional corrosion inhibitors. Traces of nitrites and chromates that are present in the inhibitors may lead to serious health and environmental issues. As a solution, organic green corrosion inhibitors have been studied to replace the conventional corrosion inhibitors. These inhibitor molecules form a protective layer on top of the metal surface to suppress metal dissolution when added to the acid solution. This process prevents direct contact between the metal surfaces and the acid environment. This study explores the usage of natural resources and biomass wastes as the basis for organic green corrosion inhibitors. This study also provides some suggestions for new biomass wastes that can be studied as new organic corrosion inhibitors, and it is aimed at opening the perspective of researchers on exploring new organic inhibitors by using natural resources and biomass wastes.

Synthesis and Characterization of New poly β-Lactam from poly acrolein and Study Corrosion Inhibition for Stainless steel in Hydrochloric Acid Solution

A new poly chain derivative of polyacrolein has been synthesized from the two basic precursors, polyacrolein and aromatic amine/substituted amine in chloroform to prepare poly Schiff base compounds (A1-A4). The novel poly subs.β-lactam derivative is obtained via coupling of poly schiff base with chloroacetyl chloride and trimethylamine (B1-B4). Newly synthesized compound was identified via spectral methods; their [13C-NMR, 1H-NMR, and FTIR] also measurement of some of its physical properties. Furthermore the inhibition effect of synthesized compounds (B1-B4) on the corrosion of stainless steel in 1N HCl was studied by wight loss method. The results of weight loss measurements showed that corrosion inhibition efficiency by increasing the concentration of organic inhibitors for stainless steel in 1M HCl solution at 30°C.

Role of Organic and Eco-Friendly Inhibitors on the Corrosion Mitigation of Steel in Acidic Environments—A State-of-Art Review

Steel has versatile application in chemical, structure and construction industries owing to its mechanical properties. However, it is susceptible to corrosion in acid environments. Thus, it requires to protect the steel from corrosion. Different types of corrosion resistance steel, coatings and inhibitors are developed to mitigate the corrosion, but, inhibitor is the best remedies to control the corrosion of steel in acid condition. Moreover, organic and green inhibitors used in acid condition for descaling, acid pickling, pipelines, boiler tubes and oil-wells. Organic inhibitors reduce the dissolution of steel in acid but, it is hazardous, expensive and needs expertise to synthesize the inhibitor. Therefore, there is utmost required to study and compile the latest research about the eco-friendly corrosion inhibitors, which showed more than 90% corrosion inhibition efficiency. In the present study, I have reviewed the state-of-arts, and compile the latest development in organic and eco-friendly corrosion inhibitor used in acid environment as well as suggested about the future scope and role of green inhibitor for sustainable society, which is economical, less hazardous and readily available from the natural sources.

Application of Organic Inhibitors to the Corrosion of Materials AISI 1070 Steel

AISI 1070 steel is a material that has corrosion when it reacts with the environment. One way to inhibit the corrosion rate is by using organic inhibitors. The organic inhibitors used mango leaves and mango rinds with variations in the concentration of organic inhibitors of 0%, 6%, and 8%, respectively. This study aimed to determine the effectiveness of mango leaf extract and mango rinds as an inhibitor against the corrosion rate of AISI 1070 Steel. The extraction was carried out using the Maceration Method. Fourier Transform Infrared (FTIR), Potenzyodinamic, and Weight Loss tests were carried out in this study. FTIR results show that both mango rinds and mango leaf have ingredients that were able to inhibit the corrosion rate, such as flavonoid functional groups including C – H, C = O, and C – O. Using the weight-loss method, the best corrosion rate was found in the mango rinds extract with a concentration of 8 mL, which was 31.784 mm/year with an inhibition efficiency of 92%. The highest corrosion rate was in 2M H2SO4 solution using potentiodynamic, without a mixture of inhibitors, that is 0.15589478 mm/year.