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Article
Publication date: 7 January 2019

Gopinath Shit and S. Ningshen

High corrosion resistance in different concentrations of nitric acid is essential for structural steels to be used for the aqueous reprocessing of spent nuclear fuels with high…

Abstract

Purpose

High corrosion resistance in different concentrations of nitric acid is essential for structural steels to be used for the aqueous reprocessing of spent nuclear fuels with high plutonium content.

Design/methodology/approach

In the present study, the corrosion resistance of type 304L stainless steel (SS) with modified composition was evaluated in different concentrations of nitric acid using surface analytical techniques, weight loss method and electrochemical measurements.

Findings

Weight loss measurement in boiling 65 per cent nitric acid showed a low corrosion rate value of about 0.2 mm/y (8 mpy) after 240 h exposure. Electrochemical measurements revealed the shift in open circuit potentials as well as corrosion potential toward more noble direction, and the results of electrochemical impedance spectroscopy studies indicated the reduction in the thickness and stability of the passive film with increasing concentration from 6 to 11.5 M nitric acid.

Research limitations/implications

The low corrosion rate observed for this steel is attributed to the higher content of Cr (19 per cent), Ni (10 per cent) and Si (0.3 per cent) and controlled minor alloying elements (S, P, B, C, etc.) in the alloy that contributed to improving the transpassive corrosion resistance and minimizing the intergranular corrosion attack. The X-ray photoelectron spectroscopic analysis revealed the composition of the passive films to be mainly of iron and chromium oxides.

Practical implications

Materials with lower corrosion rates are desirable for applications in nitric acid.

Social implications

The used of nitric acid creates a severe corrosive environment in chemical or aqueous nuclear reprocessing plants, and hence with a modified composition of type 304L SS resulting in minimizing failure of components are desirable for reducing cost and maintenance.

Originality/value

The present paper is an original work carried out by the authors on the corrosion resistance behaviors of composition modified AISI type 304L SS for nitric acid application. The effects of different nitric acid concentrations were compared to provide understanding on in applicability in boiling and high nitric acid concentrations.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 2
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 June 1997

Inder Singh, A.K. Bhattamishra and D.K. Basu

Stainless steels are very unique in that they offer a wide range and combination of resistance to corrosion, resistance to oxidation at high temperature and good mechanical…

1037

Abstract

Stainless steels are very unique in that they offer a wide range and combination of resistance to corrosion, resistance to oxidation at high temperature and good mechanical properties at room temperature. With rapid industrialization all over the world, these very properties have led to extensive use of stainless steels in different industries. Austenitic stainless steels containing molybdenum exhibit corrosion resistance in both sulphuric acid and nitric acid. Stainless steel undergoes severe attack in sulphuric acid having concentrations in the range of 20‐85 per cent, whereas they are immune to nitric acid in any concentration. However, sensitized stainless steels are prone to intergranular attack in acids, even in nitric acid. Further, the attack is aggravated in the presence of aggressive ions. Study of the behaviour of stainless steels in a mixture of acids (nitric and sulphuric acid) is lacking in the literature. This paper, therefore, discusses the performance of AISI‐316 and 316‐L in sulphuric acid and nitric acid and a mixture thereof at room temperature. It is observed that the steels are quite resistant to sulphuric acid and nitric acid, but in the acid mixture they are not so resistant, especially in AISI‐316 SS in respect of corrosion resistance, even in acid mixture containing C1 and Cu++ ions.

Details

Anti-Corrosion Methods and Materials, vol. 44 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 October 1971

M.N. Desai, G.H. Thanki and D.K. Shah

2: Aminobenzoic acids as inhibitors in nitric acid Ortho, meta and para aminobenzoic acids have been studied as corrosion inhibitors for 60/40 brass in nitric acid. Ortho and para…

Abstract

2: Aminobenzoic acids as inhibitors in nitric acid Ortho, meta and para aminobenzoic acids have been studied as corrosion inhibitors for 60/40 brass in nitric acid. Ortho and para aminobenzoic acids are cathodic in action whereas meta aminobenzoic acid acts by influencing both the cathodic and anodic reactions.

Details

Anti-Corrosion Methods and Materials, vol. 18 no. 10
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 1 June 2004

W.M.M. Huijbregts and R.G.I. Leferink

Corrosion failures due to condensing flue gases containing H2O, SO3, NOx and HCl still occur more often than might be expected. The corrosion failures can be of several types…

2578

Abstract

Corrosion failures due to condensing flue gases containing H2O, SO3, NOx and HCl still occur more often than might be expected. The corrosion failures can be of several types: general corrosion, pitting attack and stress corrosion cracking (SCC). The chemistry of condensing gases is discussed, and some examples of corrosion in large‐scale installations are presented, including blast stoves for steel production, heat recovery steam generators, and waste incineration boilers. The use of thermal insulation inside boiler casings can result in nitrate SCC when the flue gas contains high concentrations of NOx. Nitric acid from flue gas can react with carbon steel and insulation material forming ammonium nitrate and calcium nitrate. Both materials have hygroscopic properties and are very corrosive, even above the water dewpoint of the gases.

Details

Anti-Corrosion Methods and Materials, vol. 51 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 February 1997

N.J. Sanders

Stainless steel pickling is a major generator of NOx emissions and is also a major producer of nitrate effluents. Hydrogen peroxide technologies have been developed and proven to…

1136

Abstract

Stainless steel pickling is a major generator of NOx emissions and is also a major producer of nitrate effluents. Hydrogen peroxide technologies have been developed and proven to suppress NOx emissions and also to replace nitric acid in the pickling process and hence remove the problem of nitrate effluent discharge. Presents case histories to illustrate the effectiveness of hydrogen peroxide both for NOx suppression and for nitric acid‐free pickling when pickling stainless steels.

Details

Anti-Corrosion Methods and Materials, vol. 44 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 8 August 2016

S. Sivarathnakumar, G. Baskar, R. Praveen Kumar and B. Bharathiraja

Prosopis juliflora is a raw material for long-term sustainable production of bioethanol. The purpose of this paper is to identify the best combination of pre-treatment strategy…

Abstract

Purpose

Prosopis juliflora is a raw material for long-term sustainable production of bioethanol. The purpose of this paper is to identify the best combination of pre-treatment strategy implemented on the lignocellulosic biomass Prosopis juliflora for bioethanol production.

Design/methodology/approach

Pre-treatment of lignocellulosic material was carried out using acid, alkali and sonication in order to characterize the biomass for bioethanol production. Prosopis juliflora stem was subjected to steam at reduce temperature (121°C) for one hour residence time initially. Further acid and alkali treatment was carried out individually followed by combinations of acid and sonication, alkali and sonication. Sodium hydroxide, potassium hydroxide, hydrochloric acid, sulphuric acid and nitric acid were used with 3 per cent (w/v) and 3 per cent (v/v) concentration under temperature range of 60-90°C for 60 min incubation time. Sonication under 60°C for 5 min and 40 KHz frequency was carried out. Pre-treated sample were further characterised using field emission scanning electron microscope and Fourier transform infrared spectroscopy to understand the changes in surface morphology and functional characteristics.

Findings

In sono assisted acid treatment-based method, nitric acid yields better cellulose content at 70°C and removes lignin that even at increased temperatures no burning was observed.

Originality/value

The paper adds to the scarce research available on the combination of auto hydrolysis coupled with sono assisted acid/alkali hydrolysis which is yet to be practiced.

Details

Management of Environmental Quality: An International Journal, vol. 27 no. 5
Type: Research Article
ISSN: 1477-7835

Keywords

Article
Publication date: 1 December 1970

V.K.V. Unni and T.L. Rama Char

Anode weight loss and polarization studies of brass in nitric, hydrochloric and sulphuric acids indicate that the copper dissolves in the cuprous state in hydrochloric acid

Abstract

Anode weight loss and polarization studies of brass in nitric, hydrochloric and sulphuric acids indicate that the copper dissolves in the cuprous state in hydrochloric acid whereas it is in cupric form in the other two acids. In nitric acid the local cell corrosion is completely stopped, when made sufficiently anodic showing a positive difference effect.

Details

Anti-Corrosion Methods and Materials, vol. 17 no. 12
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 1 June 1956

Brightening solutions for aluminium. The chemical brightening of aluminium in mixtures based on phosphoric acid formed the subject of a series of experiments in which commercial…

Abstract

Brightening solutions for aluminium. The chemical brightening of aluminium in mixtures based on phosphoric acid formed the subject of a series of experiments in which commercial purity aluminium panels were used in order to assess the influence of the aluminium content of the bath, and the effect of temperature upon the amount of metal removed. Four mixtures were employed: phosphoric‐sulphuric acid, phosphoric‐sulphuric‐nitric acid, phosphoric‐acetic‐nitric acid and phosphoric acid‐water‐nitric acid. If a highly specular finish is required, then the presence of about 5% (by volume) of nitric acid is essential. Acetic acid reduces the tendency for the rate of attack to increase with temperature, while water increases the maximum aluminium content which can be tolerated before the bath becomes unusable. Weight loss‐time curves are given for S1, S1B, S1C, NS4, HS10WP, HS15W and an Al (99.99%), 1.25% Mg, alloy treatment times up to 5 min. in the four solutions investigated. Except for HS15W, the response was found to be good for most materials, but a loss of brightness occurred with the lower‐purity materials on anodising.— (A. W. Brace and T. S. de Gromoboy, Trans. Inst. Met. Finishing, 1956, 33, advance copy No. 2.)

Details

Anti-Corrosion Methods and Materials, vol. 3 no. 6
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 1 July 1956

Inhibitors v. nitric acid corrosion. The addition of certain surface‐active substances in fixed proportions to concentrated acids and in particular to nitric acid (S.G.I.50…

Abstract

Inhibitors v. nitric acid corrosion. The addition of certain surface‐active substances in fixed proportions to concentrated acids and in particular to nitric acid (S.G.I.50) practically inhibits any corrosion of steels and light alloys.

Details

Anti-Corrosion Methods and Materials, vol. 3 no. 7
Type: Research Article
ISSN: 0003-5599

Article
Publication date: 1 July 1968

M.N. Desai, G.H. Thanki and M.H. Gandhi

Organic compounds containing sulphur, nitrogen and oxygen atoms are capable of retarding metallic corrosion. As the thiourea molecule contains one sulphur and two nitrogen atoms…

Abstract

Organic compounds containing sulphur, nitrogen and oxygen atoms are capable of retarding metallic corrosion. As the thiourea molecule contains one sulphur and two nitrogen atoms, thiourea and its derivatives are potential corrosion inhibitors. While extensive investigations have been carried out on inhibitor properties of thiourea, due attention has not yet been paid to a systematic study of inhibitor action of thiourea derivatives. However, several substituted thioureas have been investigated as corrosion inhibitors. The applications of thiourea and its derivatives as corrosion inhibitors reported in literature up to 1967 are narrated in this article.

Details

Anti-Corrosion Methods and Materials, vol. 15 no. 7
Type: Research Article
ISSN: 0003-5599

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