Note on the electrolytic determination of copper in solutions containing nitric acid

A Simplification and Improvement in the Determination of Copper in Fabrics and Rubberized Materials

Rubber Chemistry and Technology ◽

10.5254/1.3539362 ◽

1932 ◽

Vol 5 (3) ◽

pp. 356-359

Author(s):

F. Kirchhof

Keyword(s):

Nitric Acid ◽

Colorimetric Method ◽

Test Solution ◽

Ferric Ion ◽

The Past ◽

Equivalent Quantity ◽

Determination Of Copper

Abstract The determination of small quantities of copper in fabrics and in rubberized materials can be simplified by destruction with concentrated nitric acid, which accelerates the ignition to the final ash. At the same time, this method avoids the usual danger of volatilization of copper as chloride as a result of the presence of chlorine from white factice or from cold vulcanization. Likewise, precipitation of the copper as sulfide can be avoided by repeating the precipitation of the extract from the ash, which contains predominantly aluminum and iron, with ammonia. In this second precipitation, only around 1 to 2 per cent of the total quantity of copper is retained in the precipitate and filter, and this quantity may in most cases be neglected. The ordinary colorimetric method used in the past for the detection of copper as complex cuprammonium ion can be made about ten times as sensitive by making use of the reaction: Cu+ + + 2I− → CuI + I. This is, however, applicable only in the complete absence of the ferric ion and of nitric acid in the test solution. The sensitivity can be increased still more by the addition of starch. Another advantage of the determination of copper by measurement of the equivalent quantity of iodine lies in the fact that, if necessary, only one-tenth as much sample need be used, but in this case as in all such determinations, the copper must be distributed uniformly throughout the material to be analyzed.

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Electroanalytical determination of copper and lead in nitric acid solution containing small amounts of hydrochloric acid

Journal of Research of the National Bureau of Standards ◽

10.6028/jres.022.006 ◽

1939 ◽

Vol 22 (6) ◽

pp. 697 ◽

Cited By ~ 13

Author(s):

J.A. Scherrer ◽

R.K. Bell ◽

W.D. Mogerman

Keyword(s):

Nitric Acid ◽

Hydrochloric Acid ◽

Acid Solution ◽

Nitric Acid Solution ◽

Determination Of Copper

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VOLTAMETRIC DETERMINATION OF Cu IN FUEL USING CHEMICALLY MODIFIED ELECTRODE BY TETRAZOLES

Periódico Tchê Química ◽

10.52571/ptq.v16.n31.2020.668_periodico31_pgs_660_673.pdf ◽

2019 ◽

Vol 16 (31) ◽

pp. 660-673

Author(s):

Lucy Rose de Mª O MOREIRA ◽

Janiciara Botelho SILVA ◽

Jethânia Glasses Cutrim FURTADO ◽

Aldaléa Lopes Brandes MARQUES ◽

Cícero Wellington Brito BEZERRA ◽

...

Keyword(s):

Nitric Acid ◽

Modified Electrode ◽

Metal Ion ◽

Limit Of Detection ◽

Chemically Modified Electrode ◽

Chemically Modified ◽

Environment And Health ◽

Certainty Level ◽

Determination Of Copper

This article describes an analytical procedure for the determination of copper in fuel samples using the modified graphite electrode basal pyrolysis (BPPGME) by tetrazolium salts: 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2Htetrazolium (MTT) Br]. The determination of metals in fuel is an issue of environmental relevance because it believes that these elements can be released into the atmosphere causing damage to the environment and health. Fuel samples (ethanol, biodiesel and gasoline) were previously digested in a microwave oven using nitric acid and peroxides (biodiesel) and only nitric acid (alcohol and gasoline). The metal ion studied reacted on the surface of the chemically modified electrode to produce marked changes in the corresponding voltammograms. In order to determine the species of interest the best results were at pH 5.0 for copper and pH 6.0 for other species. The concentration scale for copper was 2.0x10-6 at 1.25 X 10-5 mol L-1. The limit of detection in fuels of samples (ethanol, biodiesel or gasoline), by ARV was 2.5x10-6 mol L-1. The accuracy of the proposed technique was compared by providing similar results, ie the copper concentration in the samples analyzed by both techniques at a non-statistically different 95% certainty level.

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