SU1661247A1 - Method of manufacturing anode for electrolytic production of manganese dioxide - Google Patents

Abstract

The invention relates to the manufacture of anodes used for the electrolytic production of manganese dioxide. The goal is to increase the service life, simplify the manufacturing technology and regenerate the anode, improve the quality of the target product. This goal is achieved by the development of the base surface when applying macro-hollows of arbitrary shape, having a width of 1.5-2.5 mm, a depth of 1.5-3.0 mm and occupying 10-90% of the geometric surface, micro-deepening is applied to the entire surface dredging depth from 0.04 to 0.05 mm. As a protective layer using β-manganese dioxide. 1 dw., 2 tab.

Description

The invention relates to electrochemical production, in particular to the production of anodes used to produce manganese dioxide by electrolysis.

The purpose of the invention is to increase the service life, simplify the manufacturing technology and enable the anode to be regenerated while maintaining the quality of the target product.

The drawing shows the anode section.

This goal is achieved by the fact that on the surface of the anode, made of titanium or its alloy, uniformly applied macro-deepening of arbitrary shape, having a width of 1.5-2.5 mm, a depth of 1.5-3.0 mm and occupying 10-90% the geometrical surface, then the entire surface of the anode is covered with microdensings, having the form of grooves with a depth of 0.04-0.5 mm, followed by the application of / 3-manganese dioxide on it.

Macrodepressions have an arbitrary shape and cover 10-90% of the geometric surface of the anode. Macro grooves have a width of 1.5-2.5 mm and a depth of 1.5-3.0 mm. The minimum width and depth of the macro depths is taken to be 1.5 mm, since at lower widths and depths the anode service life decreases, and above the maximum accepted value 2.5 mm the mechanical strength of the titanium anode base deteriorates.

Macro-deepening on the surface of the anode is obtained by any known method: by machining on a lathe, crimping, pressing, stamping, etc. Moreover, the length of the macro-deepening can be arbitrary.

Microchips cover the entire visible surface of the anode and are in the form of grooves with a depth of 0.04–0.5 mm. The minimum depth of the grooves of the micropits is 0.04 mm, because the lower value

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It does not ensure reliable adhesion of the manganese dioxide layer to the titanium base, and the depth of the grooves above 0.5 mm is not rational, since at higher values the adhesion deteriorates. The micro depths are obtained by any known method that allows the specified depth to be achieved: plasma spraying 0.04-0.05 to 0.02-0.25 mm; shot blasting - from 0.04-0.05 to 0.1-0.15 mm; mechanical indentation - from 0.1-0.15 to 0.4-0.5 mm, etc. (Table 1).

Microcavities provide good adhesion of the protective layer / -duptoxide of manganese to the titanium base, and the macrogrutings allow a relatively thick protective coating / MnO2 to be bonded to the base. They significantly increase the anode service life.

The anode contains macro-deepening 1, micro-deepening 2, titanium base 3, and a layer of manganese 2 -dioxide.

The regeneration of spent anodes is carried out by their cathodic polarization in a 2–3% solution of sulfuric acid or in a conventional working electrolyte used to produce electrolytic manganese dioxide followed by the application of micro-penetrations and 3-manganese dioxide. The anodes thus produced are tested during electrolysis to produce manganese dioxide on them. With each anode, electrolysis is carried out for several cycles. The electrolysis mode and electrolyte composition were forced relative to the accepted optimal values of these characteristic parameters of the MnO2 deposition process. In all experiments, lead is used as the cathode material. The result of each test is evaluated by the final voltage on the electrolyzer, the current output and the existing GOST,

Table 2 shows examples of testing under various conditions of anodes manufactured by the proposed method.

After the end of each electrolysis cycle, the electrolytic manganese dioxide precipitate is mechanically kicked off from the anode and analyzed.

With repeated use of the anode

no damage to the protective layer / 3-Mpo2 is observed. From cycle to cycle, the anode maintains an active state to manganese dioxide electroplating.

The approximate service life of the anode without regeneration is 4-5 years, and with regeneration it is at least 20 years. For a known anode, the service life is 4-5 years.

Efficiency of anode manufactured

The proposed method consists in the fact that with an increase in the service life and the possibility of its repeated use, the process of producing electrolytic manganese dioxide also becomes cheaper.

This is due to the fact that the manufacture of the anode is carried out according to a simplified technology using mechanized means and does not require the use of scarce and expensive materials that adversely affect the quality of the target product.

Claims (1)

Invention Formula A method of making an anode for the electrolytic production of manganese dioxide, comprising machining the base of titanium or its alloy to create a developed surface, followed by applying a protective A layer, characterized in that, in order to increase the service life, simplify manufacture and enable the anode to be regenerated, when machining on the surface, macro-deepening of arbitrary shape is performed, having a width of 1.5-2.5 mm, a depth of 1.5-3, 0 mm and occupying 10-90% of the visible surface, and then on the whole surface micro-digging, shaped as recesses depth of 0.04-0.05 mm, and as a protective layer using D-manganese dioxide. Macro deepening 0.70 Note. The brackets indicate the average value for each experiment.