scholarly journals Corrosion-Inhibitor Efficiency Control: Comparison by Means of Different Portable Corrosion Rate Meters

CORROSION ◽  
2010 ◽  
Vol 66 (2) ◽  
pp. 026001-026001-12 ◽  
Author(s):  
I. Martínez ◽  
C. Andrade ◽  
N. Rebolledo ◽  
L. Luo ◽  
G. De Schutter
Keyword(s):  
Corrosion Rate ◽  
Corrosion Inhibitors ◽  
Inhibition Efficiency ◽  
Small Areas ◽  
Extended Technique ◽  
Large Structures ◽  
Control Comparison ◽  
Efficiency Control ◽  
Bare Steel ◽  
Rate Calculation

Abstract Corrosion-inhibiting substances have been applied to suppress corrosion mainly on bare steel, but when corrosion is progressing, suppression can be achieved if anodic and cathodic reactions are avoided, which is not an easy objective, particularly if the bare metal is surrounded by concrete. In the present article, several corrosion inhibitors are studied to identify their inhibition efficiency in concrete. The percentage of reduction of the corrosion rate without and with inhibitor is named “inhibition efficiency.” This definition calls for the measurement of the corrosion rate and makes its measurement a must when studying corrosion-inhibiting substances. The most extended technique used for the corrosion rate quantification is based on the calculation of the polarization resistance, Rp. For the study presented in this article, several portable corrosion rate meters based on the Rp technique have been used. These equipment are needed for the evaluation of large structures and are able to confine the current in small areas or to determine the steel area affected by the signal for a correct corrosion rate calculation. A comparison among the different corrosion rate meters used for the inhibitor's efficiency has been done. This comparison has indicated that the corrosion rate meter with nonefficient confinement of the current is not able to detect clearly the passivation state.

scholarly journals Ethanolamines as Corrosion Inhibitors for Zinc in (HNO3+H2SO4) Binary Acid Mixture

2010 ◽  
Vol 7 (2) ◽  
pp. 665-668 ◽  
Author(s):  
R. T. Vashi ◽  
H. M. Bhajiwala ◽  
S. A. Desai
Keyword(s):  
Corrosion Rate ◽  
Acid Concentration ◽  
Corrosion Inhibitors ◽  
Inhibition Efficiency ◽  
Corrosion Behaviour ◽  
Acid Mixture ◽  
Inhibitor Concentration

This work deals with the study of corrosion behaviour for zinc in (HNO3+ H2SO4) binary acid mixture containing ethanolamines. Corrosion rate increases with concentration of acid and temperature. At constant acid concentration, the inhibition efficiency of ethanolamines increases with the inhibitor concentration. Value of ΔGa increases and inhibition decreases with temperature. The mode of inhibition action appears to be chemisorption.

scholarly journals Inhibition of Brass Corrosion in Acid Medium Using Thiazoles

2013 ◽  
Vol 14 ◽  
pp. 87-102
Author(s):  
K.K. Taha ◽  
Musa E. Mohamed ◽  
S.A. Khalil ◽  
S.A. Talab
Keyword(s):  
Weight Loss ◽  
Thermal Properties ◽  
Electrochemical Impedance Spectroscopy ◽  
Impedance Spectroscopy ◽  
Corrosion Rate ◽  
Heat Exchangers ◽  
Corrosion Inhibitors ◽  
Inhibition Efficiency ◽  
Electrochemical Impedance ◽  
Zinc Dissolution

Brass as an alloy composed mainly of copper is great industrial uses such as heat exchangers and similar other facility due to its good thermal properties. Due to the presence of the considerable ratio of zinc the alloy suffers from zinc dissolution or dezincification. Dezincification rate increases with the increase in the ratio of zinc in the alloy. In this study benzothiazole (BTH) and its substituent’s 2-methylbenzothiazole (MeBTH), 2-aminobenzothiazole (ABTH), 2-mercaptobenzothiazole (MBTH) and 2-phenylbenzothiazole (PhBTH) have been used as corrosion inhibitors for α-brass in stirred 0.1 M HClO4. The methods of investigation include weight loss, Tafel and linear polarizations and electrochemical impedance spectroscopy. The order of inhibition efficiency (%E) was calculated and the values obtained has indicated the sequence of inhibition efficiency was found to be BTH < MeBTH < ABTH < PhBTH < MBTH. The calculated values of thermodynamic parameters support this order. The inhibitors were found to suppress the corrosion rate by the formation of films which were identified by IR, SEM and EDAX techniques.

POLYVINYLPYROLLIDONE AND POLYACRYLAMIDE AS CORROSION INHIBITORS FOR MILD STEEL IN ACIDIC MEDIUM

2008 ◽  
Vol 15 (03) ◽  
pp. 277-286 ◽  
Author(s):  
S. A. UMOREN ◽  
I. B. OBOT
Keyword(s):  
Adsorption Isotherm ◽  
Corrosion Rate ◽  
Mild Steel ◽  
Acidic Medium ◽  
Corrosion Inhibitors ◽  
Inhibition Efficiency ◽  
Adsorption Process ◽  
Physical Adsorption ◽  
Activation Parameters ◽  
Temkin Adsorption Isotherm

The corrosion inhibition of mild steel in 1 M H 2 SO 4 in the presence of polyvinylpyrollidone (PVP) and polyacrylamide (PA) as inhibitors at 30–60°C was studied using gravimetric and gasometric techniques. The inhibition efficiency (1%) increased with increase in concentration of the inhibitors. Increase in temperature increased the corrosion rate in the absence and presence of inhibitors but decreased the inhibition efficiency. Both PVP and PA were found to obey Temkin adsorption isotherm and Kinetic-Thermodynamic Model of El-Awady at all the concentrations and temperatures studied. Phenomenon of physical adsorption is proposed from the activation parameters obtained. Thermodynamic parameters reveal that the adsorption process is spontaneous. PVP was found to be a better inhibitor than PA.

Paper 1: Corrosion Inhibitors as Additives to Highway De-Icing Salts-Laboratory Tests

1967 ◽  
Vol 182 (10) ◽  
pp. 124-148
Author(s):  
R. R. Bishop ◽  
D. E. Steed
Keyword(s):  
Corrosion Rate ◽  
Rock Salt ◽  
Corrosion Inhibitors ◽  
Salt Spray ◽  
Corrosion Damage ◽  
The United States ◽  
Motor Vehicles ◽  
The Road ◽  
Paint Systems ◽  
Bare Steel

Up to a million tons of rock salt are spread on the roads of England and Wales during a severe winter. It has frequently been suggested that this salt causes increased corrosion damage to motor vehicles. In North America and Scandinavia considerable interest has been shown in the use of corrosion inhibitors as additives to highway de-icing salts and at least two inhibited salts are marketed in the United States. Use of an intermittent salt spray test in the Road Research Laboratory (R.R.L.) has shown that a 3 per cent rock salt solution is about 13 times more corrosive than urban rainwater to bare steel. Polyphosphate and chromate type inhibitors were examined under these test conditions and were found largely ineffective in reducing the corrosion rate of bare steel. However, the polyphosphate inhibitor showed a large reduction in corrosion rate of damaged painted panels finished in current motor primers and full paint systems. The work is continuing.

Stems as Natural, Green, Non-Toxic Corrosion Inhibitors

2021 ◽  
Author(s):  
Jun Hong Clarence Ng ◽  
Tariq Almubarak ◽  
Hisham A. Nasr-El-Din
Keyword(s):  
Corrosion Rate ◽  
Corrosion Inhibitor ◽  
Corrosion Inhibition ◽  
Corrosion Inhibitors ◽  
Inhibition Efficiency ◽  
Environmental Concerns ◽  
Base Case ◽  
Naturally Occurring ◽  
Corrosion Inhibition Efficiency ◽  
Acid Treatments

Abstract Corrosion during acid treatments causes severe damage to the tubulars and downhole equipment. Consequently, this leads to an increase in expenditure to maintain well production rates and well integrity. NACE estimates the cost of corrosion costs to be roughly 1.372 billion USD annually to the industry, making corrosion control extremely important. Therefore, corrosion inhibitors must be included in any acid treatment formulation. This work aims to develop environmentally friendly and non-toxic corrosion inhibitors that can work in the harsh oilfield conditions. Samples of 10 different stems were tested as sources of potential corrosion inhibitors. To determine the inhibition effectiveness of the different samples, N-80 coupons were exposed to 15 wt% HCl solutions at temperatures between 77-200 °F with 2 wt% of each sample for 6 hours. In addition, a control solution containing no corrosion inhibitor was used to establish a corrosion rate for a base case. At a concentration of 2 wt%, sample 1, 2, and 3 were found to perform the best, exhibiting 94.4% to 99.9% corrosion inhibition efficiency at 77°F. Sample 8 was observed to perform the worst with a corrosion inhibition efficiency of 57.3%. At 150°F, the corrosion rate of sample 1 was found to be 0.0275 lb/ft2, while that of sample 2 was 0.0171 lb/ft2. At this temperature, sample 3 did not perform well, exhibiting a corrosion rate of 0.155 lb/ft2 and thus was not tested at higher temperatures. At 200°F, the addition of a corrosion inhibitor intensifier resulted in a corrosion rate of 0.0136 lb/ft2 for sample 1 and 0.00878 lb/ft2 for sample 2. These results show that a naturally occurring, green, non-toxic corrosion inhibitor can be developed from these stems and can comfortably pass the industry requirement for low carbon steel. Currently used corrosion inhibitors are associated with environmental concerns and severe health risks. Recent developments in corrosion inhibition technology successfully tackled the environmental concerns, but still faces issues with toxicity and performance at high temperatures. The results in this work share two new naturally occurring, green, non-toxic, high-temperature stable corrosion inhibitors that can be developed from stems and can successfully protect the tubular during acid treatments.

scholarly journals Synthesis New Pyridinium Salts as Corrosion Inhibitors for Mild Steel in 1 M H2SO4

2021 ◽  
Vol 24 (2) ◽  
pp. 14-20
Author(s):  
Rania Kareem Hameed ◽  
◽  
Mehdi Salih Shihab ◽  
Keyword(s):  
Weight Loss ◽  
Free Energy ◽  
Corrosion Rate ◽  
Mild Steel ◽  
Corrosion Inhibitors ◽  
Organic Molecules ◽  
Inhibition Efficiency ◽  
Pyridinium Salts ◽  
Inhibitor Concentration ◽  
Pyridinium Bromide

Some new pyridinium salts, namely 4-(4-Chloro-benzylidene-hydrazinocarbonyl)-1-phenyl-pyridinium bromide, C1; 4-(4-Chloro-benzylidene-hydrazinocarbonyl)-1-butyl-pyridinium bromide, C2; 4-(4-Chloro-benzylidene-hydrazinocarbonyl)-1-phencyl-pyridinium bromide, C3; were synthesized and Corrosion inhibitors for mild steel were tested in a 1M H2SO4aqueous solution at 20ºC for 24 hours using weight loss measurements. The findings revealed that the inhibition efficiency of all pyridinium bromide derivatives converges at the maximum concentration. An increase in inhibitor concentration is associated with a decrease in corrosion rate, an increase in inhibition efficiencies, and an increase in surface degree of coverage. The physisorption effects for (C1, C2, and C3) were revealed by the free energy values of adsorption, which provided useful information for predicting the interaction between the metal surface and organic molecules as corrosion inhibitors.

Seed Extracts as Natural, Green, Non-Toxic Corrosion Inhibitors

2021 ◽  
Author(s):  
Jun Hong Clarence Ng ◽  
Tariq Almubarak ◽  
Hisham A. Nasr-El-Din
Keyword(s):  
High Temperature ◽  
Corrosion Rate ◽  
Corrosion Inhibitor ◽  
Corrosion Inhibitors ◽  
Inhibition Efficiency ◽  
Environmentally Friendly ◽  
Base Case ◽  
Control Solution ◽  
Edible Seeds ◽  
Acid Treatments

Abstract Acid treatments are commonly used in the oilfield to remove inorganic scale or to stimulate formatio ns. These treatments typically consist of using hydrochloric acid (HCl), acetic acid, formic acid, or chelating agents. At elevated temperatures, these acids are highly corrosive and can cause severe damage to tubulars as well as downhole equipment. To reduce damage from these acids, corrosion inhibitors are added to the treatment solution. Corrosion inhibitors used in the oil and gas industry are typically quaternary amines or sulfur-containing compounds. These compounds adsorb to the surface of the metal, thereby reducing contact between the metal surface and the corrosive substance. However, these corrosion inhibitors are damaging to the environment and harmful to human health. Alternative new environmentally-friendly corrosion inhibitors are also either toxic to the human body or face performance limitations at higher temperature field applications. To develop new environmentally friendly and non-toxic corrosion inhibitors for high-temperature applications, 15 edible seeds were tested as alternative sources of corrosion inhibitors. In order to determine the inhibition effect of 15 different seeds, N-80 and S13Cr coupons were exposed to 15 wt.% HCl solutions at temperatures between 77-250°F with 2 wt.% of grounded seed added for 6 hours. In addition, a control solution containing no corrosion inhibitor was used to establish a corrosion rate for a base case. This paper will show the results of such seeds and attempt to provide an awareness of natural seeds extract for use as corrosion inhibitors in conjunction with well acid treatments. It was noted that out of the 15 seeds, seeds 1 and 2 were found to perform the best at these conditions, exhibiting more than 90% corrosion inhibition efficiency. Seed 4 was observed to perform the worst, exhibiting only 16.8% inhibition efficiency. At 150°F, 2 wt.% of seeds 1 and 2 were tested with seed 1 achieving a corrosion rate of 0.00253 lb/ft2 while seed 2 was unable to provide sufficient inhibition with a corrosion rate of 0.153 lb/ft2. The control solution was found to have a corrosion rate of 0.371 lb/ft2 over the 6 hours at 150°F. Seed 1 was further tested at 200°F with the addition of corrosion inhibitor intensifiers and resulted in a corrosion rate of 0.00087 lb/ft2, while at 250°F, a corrosion rate of 0.00811 lb/ft2 was observed. The tests using S13Cr also showed that seed 1 worked well as a corrosion inhibitor for CRAs. The thermal degradation of seed 1 was also examined using NMR. These results show a new naturally occurring, green, non-toxic, high-temperature applicable corrosion inhibitor that can be developed from edible seeds.

Adsorption and corrosion inhibition characteristics of two medicinal molecules

2019 ◽  
Author(s):  
Chem Int
Keyword(s):  
Hydrochloric Acid ◽  
Corrosion Rate ◽  
Mild Steel ◽  
Corrosion Inhibition ◽  
Half Life ◽  
Thermodynamic Data ◽  
Inhibition Efficiency ◽  
Gravimetric Method ◽  
Corrosive Environment ◽  
Corrosion Inhibition Efficiency

The corrosion inhibition characteristics of two medicinal molecules phenylalanine and rutin on mild steel in 1.0M Hydrochloric acid were evaluated using gravimetric method. Corrosion inhibition efficiency of 83.78 and 90.40 % was obtained respectively after seven days. However, phenylalanine showed weak accumulative higher corrosion inhibition efficiency. The presence of both molecules in the corrosive environment reduced the corrosion rate constant and increased the material half-life. Thermodynamic data calculated suggests a spontaneous adsorption of the molecules on the mild steel’s surface.

scholarly journals Corrosion Inhibition Efficiencies of Polymeric Materials on Alloy Steel in Dilute Hydrochloric Acid and Sodium Hydroxide Solutions at Ambient Temperature

2020 ◽  
Vol 7 (2) ◽  
pp. C27-C32
Author(s):  
I.E. Ekengwu ◽  
O.G. Utu ◽  
K.O. Anyanwu
Keyword(s):  
Corrosion Rate ◽  
Ambient Temperature ◽  
Alloy Steel ◽  
Corrosion Inhibition ◽  
High Density Polyethylene ◽  
Inhibition Efficiency ◽  
Polymeric Materials ◽  
High Density ◽  
Alkaline Solutions ◽  
Ph Values

A corrosion control test was conducted on alloy steel, using polymeric coatings (polyurethane, bitumen (medium airing), and high-density polyethylene) in dilute HCl solutions of pH values 4, 7, and 12, respectively for acid, neutral and alkaline solutions at ambient temperature. In the study, Eighty-four coupons of alloy steel were used. The coupons were mechanized, ground, polished, etched with natal, and weighed using a digital weighing balance (Beva 206B). The mass of each coupon was recorded according to the tag number on them. Twenty-one of the coupons were coated with polyurethane, 21 coated with medium curing bitumen (MC), and 21 coated with high-density polyethylene, while 21 were left uncoated. Seven polyurethane-coated samples, bitumen coating, and uncoated coupons were suspended in dilute HCl solutions of pH values 4, 7, and 12. Every week, one sample is taken from each of the solutions, the coatings and the corrosion products were removed, and the coupons were etched with natal. Then the coupons were reweighed, and their masses were recorded in accordance with their tag number. The weight loss per unit area of the coupons, corrosion rate, and percentage corrosion inhibition efficiencies of the coatings was calculated over seven weeks. The results obtained were tabulated and represented graphically. From the results obtained, it is seen that the corrosion inhibition efficiency of polyurethane coatings is higher compared with bitumen and polyethylene. It is also seen from the graphs that the corrosion rate of the coupons is higher in acid, a little bit lower in alkaline, and much lower in neutral solution. It is also observed that the corrosion rates fall with time as the inhibition efficiency also falls with time.

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