Corrosion Of Ferrous Metals Research Articles

Analysis of Melinjo Seed Extract as Corrosion Bioinhibitor for Ferrous Metals

The corrosion of ferrous metals is a serious issue that can reduce material durability and lead to significant economic losses. Melinjo seed extract was selected for investigation due to its potential as a corrosion inhibitor, attributed to the presence of tannin compounds capable of forming complexes that coat metal surfaces. This research aims to explore the use of melinjo seed extract as a bioinhibitor for iron, providing an effective and environmentally friendly solution. The extraction of melinjo seeds was performed using the maceration method. The melinjo seed extract was mixed with 70% ethanol to obtain an inhibitor solution. The study evaluated the corrosion rate and inhibition efficiency of iron immersed in melinjo seed extract solution at varying concentration. The results showed that melinjo seed extract has the potential to inhibit corrosion in iron. A higher concentration of melinjo seed extract correlated with a lower corrosion rate. The highest corrosion rate was 6.7x10-2 g/cm² day at 0% concentration. The lowest corrosion rate was 1.6x10-2 g/cm² day at a 15% concentration of melinjo seed extract. The optimum inhibition efficiency was achieved at the 15% concentration, which amounted to 76%. These results indicate that melinjo seed extract is an effective bioinhibitor for ferrous metal corrosion.

Corrosion effect of ferrous metals on degradation and remaining service life of infrastructure using pipe fracture as example

Corrosion of ferrous metals and its effects on degradation of mechanical properties and the remaining service life of metal structures have been a serious challenge to research community globally. This paper aims to investigate the problem thoroughly with experimental, numerical and analytical means. It presents results produced from a comprehensive experimental program on corrosion and its effect on degradation of mechanical properties of steel and cast iron. These include corrosion effects on mechanical properties at both macro level, e.g. the fundamental strength, and micro level, e.g. element composition, thereby presenting a complete cause and effect relationship for corrosion induced degradation of ferrous metals. Numerical results include corrosion effects on fracture failure for both single and mixed mode fractures. Analytical results include new solutions to first passage probability which is the most rational method in time-dependent reliability theory employed for service life prediction of structures. An example of cast iron pipe with fracture failure is provided to illustrate the proposed methodology. Test results presented in the paper can contribute to the body of knowledge of corrosion of ferrous metals with a view to service life of corrosion affected infrastructure.

THE STRENGTH OF CORROSIVE PROPERTIES OF CRUDE OILS ON FERROUS METALS

Crude oil is an unrivaled earth resource for the most of industrial applications. In the refining process of crude oil, ferrous metals play a severe role against the harsh environment while confronting adverse influences of crude oils such as the corrosion of ferrous metals. The formation of metal oxides, sulfides, hydroxides or any compound related with carboxylic group on the metal surface is known as the corrosion also mainly depends on the sulfur content, acidity, salt content and mercaptans content of relevant crude oils as well as the chemical composition of the metal. In this research it was expected to speculate the effect of such corrosive properties of Murban and Das Blend crude oils on seven different types of ferrous metals which are used in crude oil refining industry of Sri Lanka. The sulfur content, salt content, acidity and mercaptans content of each crude oil were determined by the succession of XRF analyzer, analyzer of salt and titration methods. A range of similar sized pieces of seven different types of ferrous metals were immersed in both crude oils separately and their corrosion rates were determined after 15, 30 and 45 days from the immersion by the weight loss method while observing the corroded metal surfaces under the optical microscope. The metallic concentrations in both crude oil samples after the experiment were tested by the AAS. It was found that the higher content of sulfur, acidity, mercaptans and lower content of salt in the Das blend than the Murban. According to the corrosion rates of metals, four types of metals showed higher rate of corrosion in Murban while other metals are showing higher corrosion rate in Das blend also higher metallic concentrations were obtained from Murban crude oil samples than Das Blend crude oil samples in the analysis of the AAS.

On Corrosion of Ferrous Metals in Typical Indian Soils Part I : Cast Iron

Corrodibility of cast iron in ten typical Indian soils, employing Schwerdtfeger's soil corrosion cell procedure and the physico-chemical properties of the soils responsible for their corrosivity have been determined. The results have been statistically analysed, interpreted and correlated with various factors. Corrosion of cast iron in non acidic soils (p/supH4-10) proceeds through electro-chemical mechanism. Usually the rate of corrosion is maximum at the beginning and with development of the film of corrosion products, the rate gradually decrease with time until it becomes more or less constant, 'Even' general corrosion is observed on most of the cases. The maximum penetration is directly proportional corrodibility. The corrosivity of soils in situ is directly poroportional to the moisture equivalent or, in turn, to the clay content. The corrosivity of soils increases with the concentration at soluble electrolytes. Ferric oxide present in a laterite soil functions as a cathodic depolariser and hence increases its corrosivity. In an acidic soil, the corrosion mainly proceeds through the mechanism of direct chemical reaction.

Analysing the Metabolic Capabilities of Desulfovibrio Species through Genetic Manipulation

Sulfate-reducing bacteria (SRB) are an environmentallysignificant group belonging to the anaerobic delta-Proteobacteria thatrespire sulfate for growth. From an industrial stand point, SRB pose athreat through corrosion of ferrous metals and production of toxicsulfides. The more positive aspects of the metabolism of the SRB includea robust but poorly understood hydrogen metabolism that is of interest toalternative energy studies. SRB also immobilize a number of heavy metalsthrough sulfide precipitation or through changing the redox state of themetal and thus its solubility. When metals are made less soluble, as isthe case with chromium (Cr(VI) to Cr(III)) or uranium (U(VI) to U(IV)),toxicity is reduced by limiting biological availability. Despite theeconomic and environmental impacts associated with SRB activities, ourcurrent knowledge of their metabolism is inadequate. Among the SRB,members of the Desulfovibrio genus have received most attention becausethese strains are most readily grown in pure culture. Therefore,Desulfovibrio strains have been the focus of biochemical and biophysicalanalyses, however, genetic studies have been more difficult. Over thelast 15 years, progress has been made in developing techniques for DNAtransformation, gene mutagenesis and over expression, and proteintagging. Since the last genetics of SRB review by van Dongen, 10 yearshave passed (van Dongen, 1995) and the complete genome sequences of amore » fewstrains are now available (Heidelberg, et al., 2004). This reviewhighlights the current advances in the genetic manipulation ofDesulfovibrio species and the potential use of these tools inunderstanding the metabolism of sulfate reducers for biotechnologicalpurposes.« less

Finding an effective way to inhibit carbon dioxide corrosion of ferrous metals in oil-and-gas production media

Main ways to control the carbon dioxide corrosion, type of inhibitors employed, reasons for choice of the inhibitors, and various factors determining the efficiency of inhibitors of different types in carbon dioxide oil-and-gas production media are considered.

Effect of pH Value on Corrosion Behavior of Steel in CO2-containing Aqueous Media

The dependence of the pH of the medium on the partial pressure of CO2 and temperature in the system constituted by low-carbon steel and NaCl (3%) and the effect of pH variation on the corrosion rate were studied. The mechanism of carbonic acid corrosion of ferrous metals in oxygen-free mineralized aqueous media was analyzed. The possibility of prognosticating the rate of steel corrosion on the basis of partial pressure of CO2 and pH value was considered.

Corrosion of ferrous metals by bacterially produced iron sulphides and its control by cathodic protection

Of the many unrelated types of microbes that can initiate or stimulate the corrosion of metals, the most important economically are the sulphate‐reducing bacteria. They flourish in the soil, in fresh and salt water (including heating and cooling systems) and in oil storage tanks and associated pipelines; and they have been found in all the continents including Antarctica.

Nitrosamine formation in corrosion‐inhibiting compositions containing nitrite salts of secondary amines

Abstract Dialkylammonium nitrite salts are used to inhibit corrosion of ferrous metals in various types of packaging. We have shown that these nitrite salts, solutions used in their preparation, and material in which they are packaged may be contaminated with the corresponding nitrosamines. This nitrosamine formation may represent a hazard for people involved in the preparation or use of dialkylammonium salts.

Nature of Sulphides and their Corrosive Effect on Ferrous Metals: A Review

Data on the structure and chemistry of the iron sulphides are collated. Corrosion of ferrous metals by the iron sulphides and soluble sulphide, including corrosion by the sulphate-reducing bacteria, is reviewed. Corrosion mechanisms are discussed.

Corrosion of Ferrous metals in Batch Cultures of Nitrate-Reducingu Bacteria

Abstract The corrosion of an iron/carbon alloy has been investigated in short-term experiments in batch cultures of the bacterium Escherichia coli grown in media containing two concentrations of nitrate and in a nitrate-free medium. The growth of the organism was also investigated in the above media but in the absence of metal samples. The results show that growth is affected by the presence of the metal and that the principal cause of corrosion is the formation of metabolic organic acids. The nitrite produced by bacterial reduction of the nitrate reacts with the metal to form a protective film.

The prevention of the corrosion of ferrous metals

The prevention of the corrosion of ferrous metals

Laboratory Measurement of the Corrosion of Ferrous Metals in Soils★

Abstract A method is described for setting up soil-corrosion cells using a soil-wetting procedure that gives reproducible results. By measuring the weight losses on cell electrodes made of steel and of cast iron after exposure to various soils for six months, it was possible to compare the effects of corrosion on the two materials. It was also found that the electrode weight losses correlated with the weight losses and maximum pitting on wrought ferrous specimens exposed for 10 years at the field test sites. Because the laboratory soils covered the range of corrosivity peculiar to soils, it was possible to derive empirical equations for predicting weight loss and pitting at the end of 10 years for presumably any soil. It is also shown how reasonable adjustments can be made for areas other than that of the field specimens and for exposure periods other than 10 years.

Anodic and Ordinary Corrosion of Ferrous Metals in Various Acids

Samples of ordinary, cold‐rolled, low‐carbon steel, 18‐8 chromium nickel steel, 14 per cent chromium iron, silcrome RA metal (Cr 16 per cent, Cu 1.25 per cent, Si 1.25 per cent, low C), duriron (Si 14.5 per cent, C 0.8 per cent, Mn 0.35 per cent), and durichlor (Si 14.5 per cent, Mo 3 per cent) were treated by simple immersion and also anodically with hydrochloric, sulfuric, nitric, and phosphoric acids of different concentrations. These treatments took place both at room temperature and at 60° C. The average loss in weight of each sample per unit of time was determined. In the case of the anodic treatments, the cell voltage was recorded. The numerical data are so arranged that the results obtained under any one set of conditions may be compared readily with those obtained under any other set of conditions. A brief discussion is given of some of the factors which affect the rate of anodic and ordinary corrosion of metals in acids.

Corrosion of ferrous metals in acid soils

Corrosion of ferrous metals in acid soils

The electrolytic corrosion of ferrous metals

The electrolytic corrosion of ferrous metals