Inhibition Effect of N, N'-Dimethylaminoethanol on the Corrosion of Austenitic Stainless Steel Type 304

The effect of N,N'-dimethylaminoethanol on the corrosion of austenitic stainless steel type 304 in 3M H2SO4 has been studied by weight-loss method and linear polarization measurement in different concentrations of the compound. The inhibition efficiencies of the inhibitor compound on the corrosion of the stainless steel were evaluated through assessment of the anodic and cathodic polarization curves of the alloy, the spontaneity of the electrochemical process, inhibition mechanism and adsorption isotherm. The inhibitor efficiency increased with increase in the inhibitor concentration. Results obtained reveal that the inhibitor performed effectively on the stainless steel providing good protection against pitting and uniform corrosion in the chloride containing acidic solutions. The compound act through physiochemical mechanism on the stainless steel surface and obeyed Langmuir adsorption isotherm. The values of the inhibition efficiency calculated from the two techniques are in reasonably good agreement. Polarization studies showed that the compounds behave as mixed type inhibitor in the aggressive media

Pyrimidine Derivatives as Environmentally-Friendly Corrosion Inhibitors: A Review

The perpetual quest for more efficient and environment friendly corrosion inhibitors remain a focal point in corrosion control. The use of organic compounds to inhibit corrosion has assumed great significance due to their vast applications in counteracting wastage of ferrous alloys. These compounds have shown great effectiveness for inhibiting aqueous corrosion due to film formation by adsorption on the metal surface. This paper reviews the inhibitive effect of pyrimidine derivatives as corrosion inhibitor. This class of heterocyclic aromatic organic compound has very important theoretical and practical applications. Their effect on the corrosion of metallic alloys was evaluated through assessment of various techniques and articles on their use in various investigations. The corrosion rate was found to be a function of different variables. Due attention was paid to the systematic study of inhibitor action of derivatives with much emphasis on the inhibitor type and functional groups of the molecular structure. The comprehensive discourse presented concludes, that the pyrimidine derivatives fulfill the basic requirements for consideration as an efficient corrosion inhibito

The Synergistic Effect of Chloride Ion and 1,5-Diaminonaphthalene on the Corrosion Inhibition of Mild Steel in 0.5 M Sulfuric Acid: Experimental and Theoretical Insights

International audienceThe inhibition efficiency of 1,5-Diaminonaphthalene (1,5DNA) compound was studied by itself as well as in a mixture that included sodium chloride (NaCl), noted [1.5DNA][Cl−], for mild steel in 0.5 M sulfuric acid. Gravimetric, electrochemical techniques and computational chemistry calculations were utilized for the assessment of corrosion inhibition efficiency and explanation of the mechanism involved during the corrosion inhibition process. The results show that inhibition efficiencies on mild steel increase with increase in concentration of the inhibitor and enhancement in inhibition efficiency was observed on addition of sodium chloride due to synergism. This inhibition has been attributed to the stabilization of adsorbed inhibitor film and, consequently, increasing its inhibitive properties. The [1.5DNA][Cl−] acts as mixed type inhibitor and the Nyquist curves show that with the increase in the concentration, the charge transfer resistance Rct increased. In addition, [1.5DNA][Cl−] obeyed Langmuir monolayer adsorption isotherm. Moreover, Molecular Dynamic Simulations and DFT calculations showed that [1.5DNA][Cl−] owned a higher adsorption ability

Quantum Chemical Study on the Corrosion Inhibition of Copper Using Some Thiosemicarbazides and Tetrazoles

Relationships between corrosion inhibition efficiency of two thiosemicarbazide based compounds namely; 4-phenyl thiosemicarbazide (PTSC), Salicylaldehyde thiosemicarbazone (STSC) and 4 tetrazole derivative; 5-Mercapto-1-methyltetrazole (MMTA), 5-(3-Pyridyl)-1H-tetrazole (PyTA), 5-Amino-tetrazole mono hydrate (ATA) and 5-phenyl tetrazole (PTA) and their molecular electronic properties have been theoretically studied at the level .............(More details are available in the full paper) Keywords: Thiosemicarbazides and Tetrazoles, structural parameters DOI: 10.7176/CMR/11-2-04

Corrosion Monitoring of Sabic Iron in Hydrochloric Acid Solutions using some Azo Compounds – Molecular Dynamics, Chemical and Electrochemical Studies

The corrosion inhibition behaviour of Sabic iron in the absence and in presence of some azo compounds derived from 2, 3-and 2, 7-dihydroxynaphthalene was investigated using weight loss, thermometry and galvanostatic polarizations techniques. It was found that, the inhibition efficiency of these compounds depends on their concentration and chemical structure. The inhibitive action of these azo compounds was discussed in terms of blocking the electrode surface by adsorption of the azo dye molecules through the active centres in their structure. The adsorption process follows Temkin isotherm. The effect of temperature on the rate of corrosion was considered and some activated thermodynamic functions were computed and discussed. Quantum chemical calculations and molecular simulations were further applied to reveal the adsorption structure and explain the experimental results

State of the art and current trends on layered inorganic-polymer nanocomposite coatings for anticorrosion and multi-functional applications

[EN] This review highlights the most important advances in the development and manufacture of advanced hybrid polymer-inorganic layered anticorrosion coatings for marine applications. These newly hybrid anticorrosion systems are gaining importance with the premise to improve the efficiency of the widely employed pure organic coatings, while widening the available types of polymeric materials employed. These could give rise to innovative high protective coatings with improved characteristics (mechanical strength, conductivity, biodegradability) or secondary functionalities (self-healing, anti-fouling). Through this document, four aspects are mainly overviewed, first, the use of 2D-layered inorganic fillers in coatings based on a barrier-type protection anticorrosion mechanism, with a special focus on graphene and its derivatives. Second, different modification strategies are presented, including covalent and non-covalent, always aiming to increase the compatibility between filler and matrix that would give as a result more efficient systems, due to 2D-layered fillers biggest drawback, their tendency to agglomerate. Third, different multi-functionalizing opportunities that graphene and its derivatives have to offer when introduced to these systems are reviewed, presenting some of the latest works reported in the past 2 to 3 years, while reviewing alternative layered structures such as natural clays or layered double hydroxides with their modifications. Fourth, different possibilities for multifunctioning these systems and their compatibility with graphene-like fillers are discussed. Finally, the conclusions and future perspectives on graphene-based anticorrosion nanocomposites are presented.R.T. wants to thank the Basque Government for funding under an FPI grant. The authors thank funding by the Spanish State Research Agency (AEI) and the European Regional Development Fund (ERFD) through the project PID2019-106099RB-C43/AEI/10.13039/501100011033. Financial support from the Basque Government Industry and Education Departments under the ELKARTEK and PIBA (PIBA-2018-06) programs is also acknowledged