The electrochemical reduction of nitrate over micro-architectured metal electrodes with stainless steel scaffold

Long-term exploitation of industrial electropolishing baths may contribute to the emergence of surface defects and may limit the range of applicable current densities. Due to this, extending the time of use of industrial baths is a major challenge. The application of electrochemical reduction in the process of reduction industrial baths enabled to reduce its contamination and, as a result, to enhance the surface quality of electropolished samples of grade 304 stainless steel. The contamination influence of the electropolishing bath on such parameters of the electropolished samples as roughness, gloss, mass reduction, and corrosion resistance was compared. The conducted tests included reduction of the contaminated industrial bath with use of cathodic reduction and monitoring of bath contamination with use of emission spectrometry ICP-OES. Potentiodynamic tests in 0.5 M chlorine environment with the aim to determine the influence of electrochemical reduction of the plating bath on surface resistance demonstrated that the pitting corrosion resistance of samples electropolished in a bath after reduction was reduced by approximately 0.1 V in comparison with samples electropolished before reduction. The calculations conducted for 24 corrosion resistance measurements demonstrated that differences between the results were significant. Bath reduction leads to improved roughness and gloss, even by approximately 500 GU (gloss units). At the same time, mass reduction decreases even by 13% in comparison with the process conducted in the bath before reduction. This may have a positive influence by slowing down the bath contamination process and, as a result, it reduces negative environmental impact. Another argument that supports the reduction of industrial baths is slowing down the process of cathode contamination during the electropolishing process. In industrial conditions, this may extend the possibility to conduct the process without the need for cathode reduction or replacement.

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Infrared Reflection-Absorption Study of the Aniline Electropolymerization on Stainless Steel

MRS Proceedings ◽

10.1557/proc-173-359 ◽

1989 ◽

Vol 173 ◽

Cited By ~ 2

Author(s):

F. Gaillard ◽

G. Bouyssoux ◽

S.N. Kumar

Keyword(s):

Stainless Steel ◽

Electrochemical Reduction ◽

Absorption Study ◽

Infrared Reflection ◽

Ftir Spectrometry ◽

Polymeric Layer

ABSTRACTPolyaniline (PANI) films were grown on 304 L steel and studied by FTIR spectrometry. The spectra of the films formed carry evidence for quinonic/aromatic alternating structure involving head-to-tail coupling. The coupling is quite independent of the thickness of the polymeric layer. The quinonic/aromatic ratio can be varied when the film is subjected to further dedoping treatments (electrochemical reduction or KOH immersion).

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An explanation of reported participation of hydrated electrons as intermediates in electrochemical reduction reactions

Canadian Journal of Chemistry ◽

10.1139/v78-003 ◽

1978 ◽

Vol 56 (1) ◽

pp. 17-23 ◽

Cited By ~ 1

Author(s):

John R. Duncan ◽

Graham A. Wright

Keyword(s):

Aqueous Solution ◽

Electron Transfer ◽

Electrochemical Reduction ◽

Experimental Test ◽

Reduction Process ◽

Conventional Theory ◽

Metal Electrodes ◽

Reduction Reactions ◽

Hydrated Electrons ◽

Species Being

Suggestions that e−(aq) is involved as a reactant in reduction reactions at metal electrodes are examined. It is shown that an experimental test of the participation of e−(aq) can be devised. The results of this test show that the conventional theory, involving electron transfer directly from the electrode to the species being reduced, provides a better explanation of the reduction process in aqueous solution.

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Assessment of measurement errors for galvanic-resistivity electrodes of different composition

Geophysics ◽

10.1190/1.2823457 ◽

2008 ◽

Vol 73 (2) ◽

pp. F55-F64 ◽

Cited By ~ 50

Author(s):

Douglas LaBrecque ◽

William Daily

Keyword(s):

Stainless Steel ◽

Measurement Errors ◽

Electrode Materials ◽

Metal Salt ◽

Central Element ◽

Steel Alloy ◽

Electric Resistance ◽

Metal Electrodes ◽

Resistivity Measurements ◽

Geophysical Surveys

This research provides an empirical study of electrodes used to measure galvanic resistivity. The central element of this work is an estimation of errors in resistivity measurements that arise because of the type of electrode material used. Fourteen types of electrodes were tested including metal electrodes, metal-salt-compound (nonpolarizing) electrodes, and one nonmetal electrode, under conditions that are typical of those encountered during geophysical surveys. Measurement errors for resistance and chargeability were estimated using the reciprocity of data from an array of electrodes such as might be used for electric-resistance tomography. The same error analysis was applied to data from a network of high-precision resistors to separate instrument errors from electrode errors. Significant differences were observed in errors produced by different electrode materials. We conclude that the choice of electrode is very important for resistivity or chargeability surveys. Iron, steel (including rebar), lead, and phosphor bronze produced the smallest errors in resistance and chargeability. Aluminum, magnesium, titanium, copper, and zinc produced the largest errors. Stainless steel (alloy 316), tin, and brass performed reasonably well, as did carbon, which was the only nonmetal tested.

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