THE ELECTROCHEMICAL DEPOSITION OF ZINC FROM AN ELECTROLYTE CONTAINING LACTIC ACID

Perelygin Yuriy Petrovich, Doctor of technical sciences, professor, dean of the Faculty Natural Sciences,
Penza State University (Penza, 40 Krasnaya str.) , enf@pnzgu.ru
Kireev Sergey Yur'evich, Candidate of technical sciences, associate professor, head of sub-department
of chemistry, Penza State University, (Penza, 40 Krasnaya str.), sergey58_79@mail.ru
Yagnichenko Natal'ya Vladlenovna, Candidate of engineering sciences, associate professor, sub-department of technosphere safety, Penza State University, (Penza, 40 Krasnaya str.), ot@pnzgu.ru

669.587

Background. The environmental hazards of the modern electroplating create a demand for a new generation of electrolytes – weak solutions which produce quality coatings with the required set of physical, mechanical and electrical properties, the performance of which is no lower than that of the existing strong electrolytes.
Materials and methods. The effect of zinc ion concentration, lactic acid in solution, pH, temperature, current density and electrolyte agitation on the cathode current efficiency and the quality of coatings has been investigated.
Results. The electrolyte composition has been elaborated and optimal electrolysis modes, allowing us to obtain high quality zinc coatings with the cathode current efficiency of 55–65 %, and the deposition rate of 4–13 μm/h have been offered.
Conclusions. The proposed electrolyte is relatively cheap, easy to produce and adjust, its performance is not inferior to the currently applicable subacid galvanization electrolytes. Lactic acid used in the electrolyte is a low toxic, biodegradable, cheap and readily available additive.

zinc coatings, lactic acid, corrosion protection, electrodeposition, electrolyte.

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