scholarly journals A Study of 1-Benzyl-3-phenyl-2-thiourea as an Effective Steel Corrosion Inhibitor in 1.0 M HCl Solution

2021 ◽  
Vol 2021 ◽  
pp. 1-14
Author(s):  
Quy Huong Dinh ◽  
Tran Duong ◽  
Nam Pham Cam

1-Benzyl-3-phenyl-2-thiourea (BPTU) was studied as a steel corrosion inhibitor in 1.0 M HCl solution. Experimental methods were conducted including potentiodynamic polarization measurement (PPM), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy (SEM) analysis. Quantum calculations were performed at B3LYP/6-311G(d,p). Hexamethylenetetramine (URO) was selected for comparison with BPTU. The results showed that BPTU with the concentration of 2 × 10−4 M and at the temperature of 30°C could protect the steel surface with the highest inhibition efficiency of 94.99% and 94.30% according to EIS and PPM, respectively. High temperature decreased BPTU’s ability to inhibit the steel corrosion. The adsorption of BPTU on the steel surface is followed by the modified Langmuir isotherm. Quantum chemical calculations showed that the thiourea functional group is the main adsorption center of BPTU. The experimental results are completely consistent with theoretical calculations.

2015 ◽  
Vol 44 (6) ◽  
pp. 371-378 ◽  
Author(s):  
Y. Sangeetha ◽  
S. Meenakshi ◽  
C. Sairam Sundaram

Purpose – The purpose of this paper is to develop an eco-friendly corrosion inhibitor for mild steel in 1 M HCl. Design/methodology/approach – A pharmaceutical drug acetyl G was investigated for its corrosion inhibition efficiency using weight loss method, potentiodynamic polarisation and electrochemical impedance spectroscopy. Findings – The inhibition efficiency increased with increase in inhibitor concentration. Results from polarisation studies revealed mixed type of inhibition. Impedance studies, scanning electron microscopy and Fourier transform spectroscopy confirm the adsorption of inhibitor on the mild steel surface. Research limitations/implications – The drug acetyl G has sulphur and nitrogen atoms which effectively block the corrosion of mild steel and is non-toxic and has good inhibition efficiency. Practical implications – This method provides an excellent, non-toxic and cost-effective material as a corrosion inhibitor for mild steel in acid medium. Originality/value – Application of this drug as a corrosion inhibitor has not been reported yet in the literature. Replacing the organic inhibitors, this green inhibitor shows excellent inhibition efficiency. This is adsorbed excellently on the mild steel surface due to the presence of long chain and hetero atoms. Thus, the drug retards the corrosion reaction.


2021 ◽  
Vol 39 (2) ◽  
pp. 109-122
Author(s):  
Lekan Taofeek Popoola

Abstract This paper investigated optimization of corrosion inhibitory attributes of mixed cocoa pod-Ficus exasperata (CP-FE) extracts towards mild steel in 1.5 M HCl using central composite design. Potentiodynamic polarization, linear polarization resistance and electrochemical impedance spectroscopy measurements were used for the electrochemical study. The result revealed maximum inhibition efficiency of 91.52% at temperature, inhibitor concentration, time and acid concentration of 50 °C, 5 g/L, 144 h and 0.2 M, respectively with R 2 value of 0.9429. Central composite design predicted optimum point of 70.37 °C, 3.81 g/L, 127.37 h and 0.22 M. Potentiodynamic polarization revealed extract to be mixed-type inhibitor with anodic prevalence. Electrochemical impedance spectroscopy showed that corrosion inhibition occurred via adsorption of CP-FE molecules on active sites of MS surface. Scanning electron microscopy images revealed protection of mild steel surface by adsorbed molecules of CP-FE extracts. Fourier transform infrared revealed presence of carboxyl (–COOH), unsaturated (–C-C–) and hydroxyl (–OH). Energy dispersive spectroscopy revealed presence of high iron composition on mild steel surface in the presence of mixed CP-FE extract proving its corrosion inhibition efficiency in 1.5 M HCl. Atomic adsorption spectroscopy revealed loss of Fe2+ into free HCl solution. Generally, extract from mixed CP-FE was found as effective corrosion inhibitor for mild steel in 1.5 M HCl solution.


Processes ◽  
2021 ◽  
Vol 9 (9) ◽  
pp. 1642
Author(s):  
Mingxing Liu ◽  
Dayu Xia ◽  
Ambrish Singh ◽  
Yuanhua Lin

This paper studies the corrosion inhibition performance and mechanism of dextrin (Dxt) and its graft copolymer with caprolactam (Dxt-g-CPL) on J55 steel in 1 M HCl solution. Caprolactam is grafted and copolymerized with dextrin by a chemical synthesis method, to obtain a dextrin graft copolymer corrosion inhibitor. The composition of the synthesized graft copolymer was characterized by FTIR to identify whether the grafting was successful. Through weightlessness, electrochemical impedance spectroscopy (EIS), potentiodynamic polarization curve (TAFEL), scanning electrochemical microscope (SECM), scanning electron microscope (SEM), and contact angle experiments, the graft copolymer to J55 steel in 1 M HCl solution and the corrosion inhibition performance were evaluated. Moreover, we discuss its corrosion inhibition mechanism. The dextrin graft copolymer has good corrosion inhibition performance for J55 in 1 M HCl solution. When the concentration of the corrosion inhibitor increases, the corrosion inhibition efficiency will also increase. At a certain concentration, when the temperature rises, the corrosion inhibition efficiency will gradually decrease. When the concentration is 300 mg/L, it has a better corrosion inhibition effect, and the corrosion inhibition efficiency is 82.38%. Potential polarization studies have shown that Dxt-g-CPL is a mixed corrosion inhibitor, which inhibits both the cathode and the anode of the electrode reaction. SEM, SECM, and contact angle analysis results show that Dxt-g-CPL can significantly inhibit corrosion. Compared with Dxt, Dxt-g-CPL has a better inhibitory effect.


2021 ◽  
Vol 11 (2) ◽  
pp. 3509-3512

The temperature effect of 4-ethyl-1-(4-oxo-4-phenylbutanoyl)thiosemicarbazide (EOPT) on the mild steel corrosion in 1 M HCl solution was studied by gravimetric techniques at temperatures varying from 303 to 333 K. The investigated inhibitor concentrations were started from 100 ppm and ended with 500 ppm. The inhibition efficiency increased with the increase of the concentration of the inhibitor and reached 96.1% with the concentration of 500 ppm at 303 K and decreased to 66.3% at 333 K. Moreover, the inhibition efficiencies decreased with the temperature increase for both acids. Using the Langmuir adsorption isotherm for the adsorption of this inhibitor on the mild steel surface was determined. EOPT was found to be an efficient corrosion inhibitor due to its structural molecules, which contain sulfur, nitrogen, and oxygen, hetero atoms an addition to the aromatic ring.


2019 ◽  
Vol 26 (02) ◽  
pp. 1850148
Author(s):  
N. GHARDA ◽  
M. GALAI ◽  
L. SAQALLI ◽  
N. HABBADI ◽  
R. GHAILANE ◽  
...  

The extraction of linseed oil (LO) was realized by refluxing method. The extracted oil was identified by gas chromatography method coupled with mass spectrometry (GC-MS). In order to contribute to the protection of the environment, one contemplates to try on LO as a green corrosion inhibitor. The corrosion inhibition of LO was studied by weight loss and electrochemical methods. The obtained results showed that the LO is an effective inhibitor of the carbon steel corrosion in 1[Formula: see text]M HCl solution, the inhibition efficiency increased with concentration to reach 88% at 200[Formula: see text]ppm. Furthermore, the adsorption of the inhibitor on the surface of metal in 1[Formula: see text]M HCl solution was found to obey Langmuir’s adsorption isotherm. The influences of temperature were also studied in the range from 298[Formula: see text]K to 328[Formula: see text]K. The kinetic and thermodynamic data of activation dissolution process were determined and discussed.


Materials ◽  
2021 ◽  
Vol 14 (15) ◽  
pp. 4206
Author(s):  
E. Sanchez-Salazar ◽  
E. Vazquez-Velez ◽  
J. Uruchurtu ◽  
J. Porcayo-Calderon ◽  
M. Casales ◽  
...  

A gemini surfactant imidazoline type, namely N-(3-(2-fatty-4,5-dihydro-1H-imidazol-1-yl) propyl) fatty amide, has been obtained from the fatty acids contained in the mango seed and used as a CO2 corrosion inhibitor for API X-120 pipeline steel. Employed techniques involved potentiodynamic polarization curves, linear polarization resistance, and electrochemical impedance spectroscopy. These tests were supported by detailed scanning electronic microscopy (SEM) and Raman spectroscopy studies. It was found that obtained gemini surfactant greatly decreases the steel corrosion rate by retarding both anodic and cathodic electrochemical reactions, with an efficiency that increases with an increase in its concentration. Gemini surfactant inhibits the corrosion of steel by the adsorption mechanism, and it is adsorbed on to the steel surface according to a Langmuir model in a chemical type of adsorption. SEM and Raman results shown the presence of the inhibitor on the steel surface.


2011 ◽  
Vol 194-196 ◽  
pp. 157-164 ◽  
Author(s):  
Lei Zhang ◽  
Sheng Tao Zhang ◽  
Xiao Li

The inhibition effect of tinidozole on the corrosion of mild steel in 3% HCl solution has been investigated through weight loss measurements, potentiodynamic polarization, electrochemical impedance spectroscopy (EIS) and quantum chemical calculations methods. The results show that tinidazole is an effective inhibitor for mild steel corrosion in HCl solution, and that the inhibition efficiency reaches a maximum value of 62% at the concentration of 400mg/L. Polarization measurement suggests that the tinidozole acts as mixed-type inhibitor. The Langmuir adsorption isotherm is proposed to interpret the interaction for the inhibitor molecule on metal surface. Furthermore, the quantum chemical calculation reveals that the adsorption of tinidozole is mainly concentrated around the imidazole ring.


2021 ◽  
pp. 2150084
Author(s):  
A. ZAABAR ◽  
R. AITOUT ◽  
D. AMOURA ◽  
R. MAIZIA ◽  
D. AIT ABDESSELAM ◽  
...  

In this work, we have tested a new inhibitor formulation that is effective, economically efficient and in accordance with environmental legislation. The inhibitor tested is the crude extract of the oat plant (denoted as OE) obtained by the reflux method in the water. This extract is then used as a corrosion inhibitor of mild steel in 3% NaCl. This study was carried out by using electrochemical polarizations, Electrochemical Impedance Spectroscopy and gravimetric techniques. The results obtained showed that this extract satisfactorily inhibits the dissolution rate of mild steel. The inhibition efficiency increases with inhibitor concentration and reaches 72% at 5[Formula: see text]g[Formula: see text][Formula: see text][Formula: see text]L[Formula: see text] of oat extract. Polarization data indicate that the extract acted as mixed type. The adsorption of the inhibitor on the mild steel surface in 3% NaCl follows the Langmuir adsorption isotherm. SEM analysis of the electrode surface condition confirms the results obtained.


2019 ◽  
Vol 6 (8) ◽  
pp. 190192
Author(s):  
H. H. Zhang ◽  
C. K. Qin ◽  
Y. Chen ◽  
Z. Zhang

Three new benzaldehyde thiosemicarbazone derivatives namely benzaldehyde thiosemicarbazone (BST), 4-carboxyl benzaldehyde thiosemicarbazone (PBST) and 2-carboxyl benzaldehyde thiosemicarbazone (OCT) were synthesized and their inhibition effects on mild steel corrosion in 0.5 M H 2 SO 4 solution were studied systematically using gravimetric and electrochemical measurements. Weight loss results revealed that PBST exhibited the highest inhibition efficiency of 96.6% among the investigated compounds when the concentration was 300 µM. The analysis of polarization curves indicated that the three benzaldehyde thiosemicarbazone derivatives acted as mixed type inhibitors and PBST and OCT predominantly anodic. The adsorption process of all these benzaldehyde thiosemicarbazone derivatives on Q235 steel surface in 0.5 M H 2 SO 4 solution conformed to Langmuir adsorption isotherm. Scanning electron microscopy was conducted to show the presence of benzaldehyde thiosemicarbazone derivatives on Q235 mild steel surface. The results of theoretical calculations were in good agreement with that of experimental measurements.


2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
J. P. Flores-De los Ríos ◽  
M. Sánchez-Carrillo ◽  
C. G. Nava-Dino ◽  
J. G. Chacón-Nava ◽  
J. G. González-Rodríguez ◽  
...  

The effect ofOpuntia ficus-indica(Nopal) as green corrosion inhibitor for carbon steel in 1 M HCl solution has been investigated by using weight loss tests, potentiodynamic polarization curves, and electrochemical impedance spectroscopy measurements. Also, scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR) analysis were performed. The inhibitor concentrations used ranged from 0 to 300 ppm at 25, 40, and 60°C. Results indicated the inhibition efficiency increases with increasing extract concentration and decreases with the temperature, and the inhibitor acted as a cathodic-type inhibitor which is physically absorbed onto the steel surface. In fact, the adsorption of the inhibitor on the steel surface follows the Langmuir adsorption isotherm, indicating monolayer adsorption. The presence of heteroatoms such as C, N, and O and OH groups were responsible for the corrosion inhibition.


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