RU2304639C2 - Electrode unit of electrolyzer - Google Patents

Abstract

FIELD: hydrometallurgy, possibly electrolytic extraction of noble, rare and non-ferrous metals out of diluted solution of their salts.

SUBSTANCE: electrode unit includes cathode and anode parts. Anode part is in the form of electrically non-conducting chamber having perforated walls, lower opening for supplying solution, gas discharging tubes and upper slit for introducing anode plate into it along guides. Cathode part includes two perforated current supply leads secured to walls of chamber; laminate cathode of activated carbon fibrous material forced by means of electrically non-conducting grids is fastened to said current supply leads at two sides. Polymeric net is arranged under said grids. All structure is tightened by means of bolts.

EFFECT: enhanced efficiency of electrolyzer for extracting metals out of diluted solutions.

2 dwg

Description

The invention relates to hydrometallurgy and can be used in electrolyzers to extract noble, rare and non-ferrous metals from dilute solutions of their salts.

Known electrode chamber containing a volume-porous flow-through cathode made of carbon fiber material, fixed between the lattice current leads through perforated clamps (ed. Certificate. USSR No. 395497). The disadvantage of this device is its low efficiency, especially when working with dilute solutions.

Also known is the design of a three-section cathode chamber, protected by RF patent No. 2054055 C1, consisting of a perforated housing with a cover, an internal frame with an opening for introducing the solution, current lead, and zigzag-laid carbon-graphite material, in the bends of which aluminum shavings are placed.

The whole design does not provide simplicity and convenience in operation and maintenance.

The closest prototype of this invention is (RU 2109088 IPC С25С 7/00 dated 04/20/1998) an electrode unit containing a current-conducting chamber with perforated walls, two perforated current leads with a cathode of activated carbon material attached to it, pressed by current-conducting gratings, attached to them polymer nets.

This device does not allow to expand the area and volume of carbon cathodes, thereby relatively increasing the amount of metal extracted from the solution.

The objective of the present invention is to increase the efficiency of the electrolyzer with the electrode unit for the extraction of metals from dilute solutions.

The problem is solved by implementing the technical result, which consists in creating an additional electric field inside the unit that intensifies the electrode deposition process of the metal in the entire cathode volume from activated carbon fiber material.

The essence of the invention lies in the fact that in the electrode block consisting of the cathode and anode parts an anode plate is inserted, which is placed in a non-conductive chamber. Perforated current leads are fastened to the latter from two sides through current-conducting gratings, onto which the cathode of activated carbon fiber material is laid in several layers on the external and internal sides.

When current is applied to the anode plate and current leads of the carbon cathode, an electric field appears inside the electrode block, which creates additional conditions for accelerating the extraction of metal and its deposition not only on the surface, but throughout the entire volume of the multilayer cathode made of carbon material placed on both sides of both current leads .

The invention is described in more detail below as an example of its implementation with reference to the scheme, where

figure 1 is a General diagram of the electrode unit in section;

figure 2 - schematic diagram of the placement of the electrode unit in the cell, top view.

Figure 1 shows the electrode block, divided into cathode and anode parts.

The anode part is a current-conducting chamber (1) with perforated walls. At a distance of at least 30.0 mm from these walls, an anode conductive plate (2) is inserted through the upper slot, which is fixed in a vertical position by guides on the end walls at a distance of at least 25.0 mm from the bottom of the chamber into which the fitting (3) is inserted for feed solution. Vent tubes (4) are located in the lid of the chamber.

If necessary, made of a non-conductive material, for example polypropylene, the camera can be replaced with a frame of the same material with a similar design. To improve the circulation of the solution in the chamber, the anode plate can be cut into two-thirds of its length into separate narrow longitudinal strips.

The cathode part is divided into two sections, each of which includes perforated current leads (5). At least two layers of the cathode of activated carbon fiber material are laid on both sides of them (6). Mesh (7) made of polystyrene, for example, is placed on the material. The cathode with grids is pressed on both sides to the current leads by conductive gratings (8).

The cathode thus assembled is attached on both sides to the walls of the anode chamber, and the entire structure is pulled together by bolt fasteners (9).

If necessary, for more reliable sealing of the block, the chamber walls and clamping grids at the edges can be gummed with chemically resistant rubber.

As shown in figure 2, the electrode unit (10) is placed in the cell (11) between the anodes (12) and works as follows.

The electrolyte enters the chamber (1) of the block through the lower fitting (not shown), passes through the chamber walls, pressure grids, polymer grids, perforated current leads (5) and comes into contact with all layers of the cathode made of carbon material (6). Then, the treated solution enters the electrolysis bath and, through the on-board pockets (13), merges into the outlet pipe.

The advantages of the proposed design compared to the prototype are a twofold expansion of the working area and volume of the carbon cathode, as well as the intensification of metal deposition with a uniform distribution of potential on both the external and internal side of the cathode facing the anode part due to the presence of an additional electric fields inside the block.

This allowed, ceteris paribus, to increase the productivity of the electrolyzer with the considered electrode unit by about 1.5-2.0 times with a slight (less than 30%) increase in energy consumption.

Obviously, the implementation of the present invention can be carried out in various ways, presented in the description, which should be considered as illustrative and non-limiting.

Information sources

1. Copyright certificate. USSR No. 395497, class C25C 7/00, 1972.

2. Patent and No. RU 2004633 C1, cl. C25C 7/02, 1993.

3. RF patent No. RU 2054055 C1, cl. C25C 7/02, 1996.

4. RF patent No. RU 2109088, cl. C25C 7/00, 1998.

Claims (1)

The electrolytic cell electrode unit containing a conductive chamber with perforated walls, two perforated current leads attached to them with an activated carbon fiber material cathode pressed by conductive gratings, and polymer grids placed under them, characterized in that it comprises an anode plate placed in the conductive chamber, and the cathode is fixed on both sides of two perforated current leads.

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