International Journal for Research in Applied Science & Engineering Technology (IJRASET), 2022

Benzoic acid, salicylic acid, Anthranilic acid, 2-Nitro benzoic acid, 2-Chlorobenzoic acid compounds containing acidic group as a corrosion inhibitor for carbon steel was investigated. The study revealed that the various group such as (-COOH, OH, Cl and-NO 2) containing in organic compounds has an inhibitory action on the corrosion of carbon steel in the investigated medium. Corrosion rate of mild steel was studied using chemical weight loss method at room temperature. This research paper presents use of carboxylic group organic compounds as corrosion inhibitors for metals in 0.1N, 0.01N and 0.001N (HCl, HNO 3 and H 2 SO 4) acidic medium. A common mechanism for inhibiting corrosion involves formation of a coating, often a passivation layer, which prevents access of the corrosive substance to the metal. Organic corrosion inhibitors adsorb on the surface to form protective film, which displace water and protect it against deteriorating. Effective organic corrosion inhibitors contain nitrogen, oxygen, sulphur and phosphorus with lone electron pairs as well can contain structural moieties with π-electrons that interact with metal favouring the adsorption process. This review presents mechanisms and monitoring of corrosion, laboratory methods for corrosion study, relationship between structure and efficacy of corrosion inhibitions, theoretical approach to design new inhibitors and some aspects of corrosion.

Formazan of benzaldehyde (FB) has been prepared as a corrosion inhibitor to control the rate of corrosion. This compound has been investigated as corrosion inhibitor at room temperature for preventing mild steel corrosion in Citric acid mediums by weight loss method and by adsorption isotherm. The result showed that the corrosion inhibition efficiency of these compounds was found to vary with different acid concentration. Also, it was found that the corrosion inhibition behavior of FB is greater in 1M Citric acid and 2M Citric acid. But when it has been compared the results revealed that the inhibitor efficiency is better in 1M Citric acid than 2M Citric acid. So FB can be used has a good inhibitor for preventing mild steel material. The surface analysis study also confirms that the corrosion of the mild steel and its inhibition efficiency by the inhibitor FB

Results in Physics, 2018

Mild steel is a metal which is commonly used in industrials and manufacturing of equipment for most industries round the world. It is cheaper cost compared with the other metals and its durable, hard and easy-to-wear physical properties make it a major choice in the manufacture of equipment parts. The main problem through the uses of mild steel in industry is its resistance against corrosion, especially in acidic solutions. This case led to raise the cost of maintenance of equipment that used mild steel and as a result increased costs for the company. Organic corrosive inhibitors that also act as green chemicals, 4-hydroxybenzylideneaminomethyl-5-ethyl-1,3,4-thiadiazolhave been synthesized. This inhibitor is tested as corrosion inhibitor on a mild steel sample MS in 1M hydrochloric acid solution (HCl) using electrochemical measurements test includes PD (Potentiodynamic), EIS (Electrochemical impedance spectroscopy), OCP (Open circuit potential) and EFM (electrochemical frequency modulation). The obtained results indicate that 4-hydroxybenzylideneaminomethyl-5-ethyl-1,3,4-thiadiazol acts as a good corrosion inhibitor for mild steel sample in HCl solution with efficiency above 90%. Changes in the impedance parameters postulated adsorption on the mild steel specimens' surfaces of, which it going to the formation of protective coating layer. It also shows that 4-hydroxybenzylideneaminomethyl-5-ethyl-1,3,4-thiadiazolcorrosion inhibitors are 2 effective in helping to reduce and slow down the corrosion process that occurs on mild steel surface in hydrochloric acid solution. Increase of corrosion inhibitor concentration provides a protective layer of mild steel. However, this protective layer becomes weak when the temperature of the solution increases.

The enhancement of the inhibitor efficiency of formazan derivative like Formazan derivative of p-dimethyl amino benzaldehyde (FD) and Formazan of benzaldehyde (FB) on the corrosion of mild steel in acidic media of 1M H2SO4 have been investigated using weight loss measurements, electrochemical impedance spectroscopy, potentiodynamic polarization and FT-IR spectroscopic techniques. Potentiodynamic polarization studies have shown that compound FD and FB suppress both the anodic and cathodic process and they behave as mixed-type inhibitors. Changes in impedance parameters are indicative of the adsorption of these compounds on the metal surface and the inhibition efficiency was found to mainly depend on the nature of the investigated compounds. It was found from the experimental evidences that the adsorption on the mild steel surface follows the Langmuir isotherm model in all acidic media. These studies have also shown that Formazan of p-dimethyl amino benzaldehyde and Formazan of benzal...

Transactions of the Indian Institute of Metals, 2014

The aim of this work was to investigate the inhibition effect of acid garlic essential oil (GO oil) as an inhibitor on the corrosion of carbon steel in a 1M HCl solution at different temperatures by weight loss, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization methods. The GO oil acts as an effective corrosion inhibitor for carbon steel in a hydrochloric acid medium. The inhibition process is attributed to the formation of an adsorbed film of inhibitor on the metal surface which protects the metal against corrosion. The result indicates that the inhibition efficiency) increases as with the concentration of the inhibitor. The (%IE of GO oil depends on its concentration, and attains approximately 95.8% for 2.5 g/L at 298K. The effect of temperature on the corrosion behavior of carbon steel in 1 M HCl, with the addition of essential oil was also studied. The adsorption of the essential oil on the carbon steel surface obeyed the Langmuir adsorption isotherm. Values of inhibition efficiency calculated from weight loss, potentiodynamic polarization, and electrochemical impedance spectroscopy are in good agreement. Polarization curves showed that GO oil behaves as a mixed-type inhibitor. The activation energy as well as other thermodynamic parameters for the inhibition process was calculated and discussed. The results obtained showed that the acid garlic essential oil could serve as an effective inhibitor of the corrosion of carbon steel in hydrochloric acid solutions.

International Journal of Corrosion and Scale Inhibition, 2021

Mild steel is one of the most widely used construction materials that finds various applications in industry owing to its exceptional mechanical properties and low cost. However, hydrochloric acid is widely used as an efficient pickling agent in steel industries to remove rust and scales, but it accelerates steels corrosion rate. Corrosion inhibitors are one of the most effective methods used to reduce mild steel corrosion in acidic media. In this study, new synthetics organic compounds L1, L2 and L3 were examined as corrosion inhibitors for mild steel in 1 M hydrochloric acid solutions using potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM). For the examined concentrations range, it was observed that the inhibition efficiency increased with increasing L1 and L2 concentrations and decreased with increasing L3 concentration. The maximum efficiency of 69% was achieved at 300 ppm of L2 at room temperature. Based on polarization studies, all the compounds were found to behave as anodic type inhibitors. SEM micrographs showed that the used inhibitors slowed down the corrosion of the surface with fewer cracks and pits observed. The quantum chemical parameters were calculated and showed a good agreement with the experimental results.

Int. J. Electrochem. Sci, 2011

Formazan of p-dimethyl amino benzaldehyde (FD) has been prepared as a corrosion inhibitor to control the rate of corrosion. This compound has been investigated as corrosion inhibitor at room temperature for preventing mild steel corrosion in Sulphuric acid and Hydrochloric acid medium by weight loss method, electrochemical methods. The result showed that the corrosion inhibition efficiency of these compounds was found to vary with different acid concentration. Also, it was found that the corrosion inhibition behavior of (FD) is greater in 2N HCl and 2N H 2 SO 4. So (FD) can be used has a good inhibitor for preventing mild steel material.

2020

Fourheteroatom organic compounds (HAC) such as L-methionine (Meth), L-Cysteine (Syst), Phenyl MercaptoTetrazol (PMT) and Glutamic acid (GA) were evaluated as corrosion inhibitors for mild steel in 1M acetic acid (AcA) solution. The technique used are potentiodynamic polarization (PDP), electrochemical impedance spectroscopy (EIS), UV-Vis spectroscopy analysisand scanning electron microscopy (SEM). As a comparative study results, the corrosion inhibitor rankings were: Meth ˂ Cyst ˂ PMT ˂ GA. Furthermore, the GA was the best inhibitors against mild steel corrosion and provided an inhibition efficiency of 74% at 10-4 M. For this reason, we have besides studied the GA concentration and immersion time on the performance delivered by GA. In this way, it is affirmed that the inhibition efficiency was well improved with the GA concentration increasing. In addition, the GA is a good corrosion inhibitor even with long durations.

The inhibition of the corrosion of mild steel in hydrochloric acid and sulphuric acid solutions was studied using Formazan derivative of p-dimethyl amino benzaldehyde (FD). Weight loss, electrochemical impedance spectroscopy (EIS) and potentiodynamic polarization techniques was studied using this inhibitor. Inhibition was found to increase with increasing concentration of the FD. The effect of temperature, immersion time and acid concentration on the corrosion behaviour of mild steel in 1MHCl and 1MH2SO4 with addition of this derivative was also studied. The results obtained show that the Formazan derivative could serve as an effective inhibitor of the corrosion of mild steel in hydrochloric and sulphuric acid media.