Melted electrode and process for producing polyvalent metal

The present invention relates to the production of polyvalent metals, in particular titanium, zirconium and tephnium, and relates to a composite electrode and to a process with a composite electrode. The process is particularly applicable to the preparation of titanium halide melt by electrolyte electrolysis.

The electrolytic production of titanium in a salt bath differs from the various methods for the production of other monovalent metals by melting, which differ in practical problems. From an equipment design point of view, the problems stem from the cathodic precipitation of the metal in solid state and the well-known reactivity of the metal and its ions with air. An important step towards solving these problems is the solution described in European Patent Application EPA-021 0961 (the present inventor's prior invention), which discloses an apparatus for continuously carrying out the electrolytic process and eliminating the oxidation of the metal to be produced, thereby providing high productivity. and allows high quality production.

As regards the process, the electrolysis of titanium differs from other conventional methods of metal preparation in salt molten by the fact that the valence of titanium in the electrolyte differs from that of titanium in the raw material, which is slightly soluble in the electrolyte. In order to ensure efficient electrolytic extraction, titanium tetrachloride must be reduced to a divalent oxidation state well soluble in the electrolyte.

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Another important factor in the electrolysis of titanium is related to the polyvalent value of the electrolyte, the simultaneous presence of divalent and trivalent ions in the electrolyte, whereby the equilibrium state of the divalent and trivalent ions is influenced by parameters such as temperature and impurities in the electrolyte. Since the efficiency of electrolytic production is the higher the percentage of divalent titanium, the average valency of the titanium in the electrolyte should preferably be set to a low value, which may not exceed 2.1.

Another important factor in the electrolysis of titanium is the high reactivity of titanium ions in the electrolyte with nascent chlorine, both for dissolved atoms and for dispersed gases, which requires that the zone of chlorine release be separated from the rest of the electrolyte.

Due to the above reaction delay, it is also necessary to prevent the migration of titanium ions by diffusion around the anode in order to avoid oxidation of the titanium ions, reaction with nascent chlorine and the formation of TiCl3, which is volatile at the operating temperature and and maintains an ion current between the anode.

In order to improve the efficiency of titanium extraction, and in view of the difficulties associated with the factors detailed above, US-A-2,789,943 proposes a solution by inserting a conductive diaphragm surrounding the anode between the anode and the cathode.

The walls of -4 have a permeability to the electrolyte and are capable of incorporating the selected metal in the deposition form.

This diaphragm is coupled to the electrical circuit of the cell and is thus bonded to a negative potential relative to the anode in order to cathodically deposit and deposit the metal to be produced on the permeable wall of the diaphragm, which is permeable to chlorine ions but substantially migration of titanium ions from the cathode to the anode by diffusion.

EP-B-53 564 discloses a process for controlling the permeability of the diaphragm covered by the deposition of the metal to be produced by increasing or decreasing the metal deposition depending on the voltage drop inherent in the diaphragm impregnating electrolyte.

The first of the above methods does not allow for continuous operation conditions on an industrial scale, since the deposited layer containing the metal to be produced has to be removed at regular intervals and the process has to be restarted several times a day.

The latter European patent method does not allow the oxidation of divalent titanium in the cathodic compartment and consequently the average value of titanium in the bath increases, which would be avoided during the precipitation of the diaphragm, as this results in a reduction in the extraction efficiency.

The above methods require complex startup procedures.

-5, which require a significant amount of time and electricity and are difficult to control. In these processes, where the starting operation is carried out with an open diaphragm, starting with an electrolyte mass which does not contain the ions of the metal to be produced requires a series of operation steps which cannot be carried out in industrial production.

It is an object of the present invention to overcome the above problems and shortcomings. The challenge is to develop a device and method for producing polyvalent metals in a highly industrially controlled manner with high efficiency.

On the one hand, the object is solved by forming a composite electrode having at least one anode and a conductive frame electrically insulated from the anode, the anode and the conductor frame having an electrical connector, the conductor frame encircling the anode and cathodically selected towards the anode. having metal particle-receiving and electrolyte-permeable wall surfaces where, according to the invention, support members are attached to the conductor frame walls, in which are mounted separating elements adjacent to the electrolyte permeable wall surfaces, defining an electrolyte bath within the conductive frame containing a receiving space which does not contain the metal to be produced, and electrolytically separating the electrolyte permeable wall elements from

-6 are made of anodic soluble metal under given operating conditions.

Preferably, the electrolyte permeable wall surfaces are formed by lattice members formed of tile-shaped components arranged in horizontal rows and forming passages for the electrolyte.

For example, the tile shaped components may have a V-cross section.

Preferably, the anode consists of rod members and a transverse member perpendicular to the rod members, the ends of the cross member being taken up by a first concave bracket electrically connected thereto and a second concave bracket electrically insulated from it but electrically connected to the guide frame.

In the composite electrode of the invention, guides are preferably mounted on the inward facing wall surfaces of the guide frame walls.

On the other hand, in accordance with the composite electrode of the present invention, a method has been developed in which the halide of the metal to be produced is cathodically dissolved in an alkali metal or alkaline-earth metal halide electrolyte and selected by electrochemical extraction in a comprising at least one anode, at least one cathode and a conductive frame acting as an intermediate electrode, which defines an anode space and a cathode space around the anode, where the vein

The conductive frame is permeable to the electrolyte and has electrolyte permeable wall surfaces which absorb the cathodically selected metal layer, allowing ion migration between the anodic and cathodic regions, but limiting the permeability of the metal to be produced. According to the invention, the process comprises the following steps a) to f):

a) charging the extraction cell with an electrolyte containing the ions of the metal to be produced in solution,

b) providing a conductive bath with an alkali metal or alkaline earth metal halide bath, which does not contain a significant amount of metal ions to be produced, which is closed by electrolytic sealing of the electrolyte permeable wall surfaces with anodic solubility metal particles,

c) selecting the alkali metal or alkaline-earth metal by an electric current fed between the anode and the conductive frame on the electrolytic permeable wall surfaces of the conductive frame and maintaining the current until a predetermined amount of metal has accumulated,

d) with the electric current fed between the anode and the cathode, the metal to be produced is selected at the cathode and simultaneously the metal particles are dissolved anodically, thereby diffusing the metal ions to be produced from the cathode region to the anode region; by reducing it on the electrolyte permeable wall surfaces of the conductive frame,

e) maintaining the current coupled between the anode and the cathode until the metal to be produced is separated on the cathode, "

f) regulating the current flowing between the anode, cathode and conductor frame so that the permeability characteristic of the selected layer is approximately constant.

The above process is mainly used for the production of titanium, zirconium or hafnium. In the above process, in step f), the current between the anode and the conductor frame is controlled such that the rate of precipitation of the alkali metal or alkaline earth metal selected by the cathodic reduction at the interface boundary of the conductor frame to the metal atoms diffusing from the cathode space. to reduce it, and equilibrating the ion selection stream of the metal to be produced at a boundary surface of the metal to be selected at the interface of the conductor frame toward the cathodic space.

In the process of the invention, steps b) to f) are conveniently carried out using the composite electrode of the invention described above.

In a preferred embodiment of the proposed process, the cathodic dissolution of the metal halide to be produced is carried out in a separate cell separated from the extraction cell, which is connected to the extraction cell via a connecting valve and wherein the electrolyte charged to the extraction cell and carrying out the following steps g) -1) of the process:

g) arranging a select cathode and a composite electrode according to the invention in a separate cell,

h) generating and maintaining a potential difference between the anode and the conductive frame of the composite electrode until an alkaline or alkaline-earth metal accumulates on the conductive wall surfaces of the conductive frame,

i) providing an appropriate potential difference between the anode of the composite electrode and the selection cathode, whereby the particles are anodically soluble and the metal to be produced is deposited on the electrolyte permeable wall surfaces of the conductive frame, and

1) introducing into the selection cathode the tetrachloride of the metal to be produced in an amount which is stoichiometrically proportional to the current flowing at the selection cathode, thereby enriching the electrolyte to the desired value.

In a preferred embodiment of the process of the invention, the cathodic dissolution of the metal halide to be produced is carried out in a separate cell separated from the extraction cell, which is connected to the extraction cell by a cathodic valve, wherein the electrolyte charged to the extraction cell wherein the cathodic dissolution of the metal halide of the metal to be produced is accomplished using the composite electrode to select the metal to be produced on the walls of the composite electrode conductor frame, the tetrachloride of the metal to be produced is introduced into the electrolyte bath without a cathode current, and a current is applied between the anode and conductive frame of the composite electrode.

-10 {2 Ti³⁺+ 2e -> 2 Ti²⁺} equals the sum of the stoichiometrically proportional current and the current required to produce the alkali metal or alkaline earth metal at the conductive frame of the divalent metal ion composite electrode.

The above process may optionally be carried out by reducing the average valency of the metal ions dissolved in the electrolyte after enrichment of the electrolyte with the metal to be produced, to transfer the tetrachloride to a composite electrode without switching the current to the composite electrode at the boundary surface of the alkali metal or alkaline earth metal toward the anode compartment of the conductive frame and reducing the current of the trivalent titanium to the divalent titanium current at the cathodic compartment boundary surface of the conductive frame.

In the process according to the invention, the dissolving and secretion steps are carried out under atmospheric pressure.

Preferably, the electrolyte used in the process of the invention is a sodium chloride bath.

The invention will be described in more detail with reference to the drawing. In the drawing:

Figure 1 shows an example of a composite electrode according to the invention. the embodiment shown in a vertical section;

Figure 2 is a sectional view taken along line II-II of Figure 1;

3-5. Figures 1 to 5 show the composite electrode of Figure 1 · ♦ ··

-11 as an example of its part - the creative elements of the grid members! its variants can be seen in enlarged scale, in section;

Figure 6 is a schematic diagram showing the metal selection;

FIG. 7 illustrates, by way of example, an apparatus for carrying out the process according to the invention. a block diagram is shown.

As shown in FIGS. 6 to 8, the composite electrode of the present invention has a horizontal member 1 and a vertical rod-shaped member 2 for implementing the anode. The material of the cross member 1 and the rod-shaped elements 2 is preferably graphite. The rod-shaped elements 2 are connected to the cross member 1 by a tethered connection.

The rod-shaped elements 2 are surrounded in a basket-like manner by a guide frame 3. The guide frame 3 has flat side walls 4, 5, 6 and 7, and base plate 8. The upper part of the conductive frame 3 surrounds the cross member 1 of the anode, from which it is insulated with insulating sheaths 9 made of refractory insulating material. The side walls 6 and 7, the base plate 8 and the upper parts of the side walls 4 and 5 are provided with an insulating cover 10 made of refractory material.

The conductive frame 3 is mechanically and electrically connected to a concave bracket 11, but is electrically insulated from the cross member 1 of the anode. The concave bracket 11 also provides a connection end for the electrical supply of the guide frame 3 (the rectifier is not shown).

A similar concave bracket 12 is connected to the cross member 1 of the anode, which is electrically insulated from the frame 3, but is electrically connected to the cross member 1 and provides a terminal end for the electric power supply to the anode e-12.

The electrode of the present invention is preferably used in an apparatus of the type described in European Patent Application EP-A-021 0961. Said patent discloses electrodes for a suspension in a salt melt bath carried by carrier members and having an electrical connection means consisting of a pair of electrically conductive members, the electrically conductive members being attached to opposite walls of the melting vessel receiving the salt melt bath.

As shown above, by way of example! the composite electrode also has a pair of supports formed by the concave holders 11 and 12. Therefore, it is emphasized that the technical details of the electrical connections are not relevant to the electrode arrangement of the invention.

Each side wall 4 and 5 of the guide frame 3 is provided with apertures in which grid members 13 are formed of a plurality of component parts 14. Within the grid members 13, the components 14 are arranged in horizontal rows and form passageways 15 between them, which allow for electrolyte flow. 3-5. Figures 3 to 5 show three different exemplary layouts, wherein the tile shaped parts 14 are V-sections according to Fig. 3, and a semicircular cross-section according to Fig. 4; 3A and 4B. The lattice members 13 provide a receiving surface for deposition and accumulation of alkali metal or alkaline earth metal by cathodic reduction. In particular, the arrangement of the V-shaped component 14 shown in Figure 3 is particularly advantageous.

As shown in Figure 2, ceramic fiber panels 16 made of refractory material are fitted to the anode-facing side of the lattice members. On the other outwardly facing side of the lattice members 13 are lattice elements 17.

As shown in FIG. 2, the guide frame 3 is provided with exterior supports 19 and 20, between which retaining members 18 are secured and providing an electrolytic seal between the supports 19 and 20. The separating members 18 are made of metal and are preferably secured with a releasable bond. The retainers 19 and 20 in this example are annular.

The separating members 18 are preferably made of a thin sheet and are made of the metal to be produced. The separating elements 18 seal the openings in the side walls 4 and 5, thereby delimiting the saline electrolyte bath of the rod-shaped elements and at the same time preventing the electrolyte from leaking into the space surrounding the anode from outside the initial stage of the extraction process.

The composite electrode of the present invention has baffles 21 to limit the scattering caused by bubbles formed at the anode during chlorine formation and consequently to prevent electrolyte accumulation on the cross member 1 of the anode. The baffles 12 are arranged on the walls 4 and 5 of the guide frame 3.

The production of polyvalent metal by the process of the invention, which will be described in more detail below by way of example of titanium production, is preferably carried out in the prior art EP-A-021-0961.

As shown schematically in Figure 7, the apparatus comprises a melting crucible 22 which is divided into a separate cell 23 and an extraction cell 24. The separate cell 23 serves to dissolve the tetrachloride of the metal to be produced, while the extraction cell 24 serves to precipitate the metal on the cathode. The connection between the separate cell 23 and the extraction cell 24 is provided by a connecting valve 25 located near the bottom of the melting pot 22.

Let us first consider the process of metal selection. An electrolyte consisting of an alkali metal or alkaline earth metal halide bath in which titanium is present in dissolved form is introduced into the extraction cell 24. The electrolyte is preferably sodium chloride. The use of sodium chloride has several beneficial effects over other electrolytes, such as a simple liquid structure which does not form compounds that affect the titanium secretion mechanism and which precipitates on the walls of the melting pot 22 over the surface of the electrolyte bath, providing a corrosive effect against chlorine gas. .

When starting the metal precipitation process, the titanium concentration in the electrolyte bath is preferably 3-10% and the average valency of the titanium ions is not greater than 2.1.

The extraction cell 24 has at least one cathode 26 and at least one composite electrode according to the invention.

-15ve. At the start of the electrolytic selection, the conductive frame 3 of the composite electrode has separating elements 18 made of titanium sheet. Inside the conductive frame 3, an electrolyte bath consisting of a halogen salt melt, preferably a sodium chloride melt bath, containing no titanium ions, is arranged around the anode.

The temperature of the electrolyte is preferably adjusted to 800-880 ° C. The operation is carried out at atmospheric pressure.

After placing the composite electrode in an electrolyte bath in the extraction cell 24, a negative voltage relative to the anode potential is applied through rectifiers 27 between the composite electrode anode and the conductive frame 3 so that the current generated is sufficient for the alkali metal or alkaline earth metal. optionally to precipitate sodium on the lattice members 13. The tile-like design of the constituent portions 14 of the lattice members facilitates the deposition of metal sodium on the downwardly concave surfaces, since the sodium, which is lighter than the electrolyte, tends to upward in the electrolyte and thus is placed under the concave surface of the tile-shaped constituent portions. The potential difference between the anode and the guide frame 3 is maintained until a significant amount of sodium is produced on the grid members 13.

Subsequently, a voltage is applied between the anode of the composite electrode and the cathode 26, which results in the precipitation of titanium and at the same time the anodic dissolution of the separating elements 18. As a result of the anodic dissolution of the separators 18, the 3 conductors 3 · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·

-Imolecular out-of-frame electrolyte containing titanium ions and an electrolyte bath within the 3 conductive frames initiate ion movement, during which Ti²⁺ ions migrate to the anode by diffusion and are reduced to titanium metal with the help of sodium deposited on the lattice members 13. This process results in a microcrystalline deposit in the form of a porous layer which acts as a permeable diaphragm against migration of chlorine ions,²⁺ does not allow diffusion of titanium ions towards the anode. The microcrystalline layer is designated 28 in Figure 7.

Figure 6 schematically illustrates the mechanism of formation of a microcrystalline layer 28 formed by migration of titanium ions.

It should be noted that the microcrystalline layer 28 is simultaneously the site of several processes and thus acts as an electrode which performs the following functions:

1) the side facing the anode of the microcrystalline layer 28 acts as a unipolar cathode; a limited amount of sodium is deposited on the microcrystalline layer 28 with independent electrical power supply;

2) the other side of the microcrystalline layer 28 also acts as a unipolar cathode in which the following reaction occurs:

You³⁺ + e "---> Ti²⁺ thereby reducing the mean electrolyte value;

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3) the inside of the microcrystalline layer 28 also acts as a monopolar cathode, where the following half reaction occurs:

You²⁺ + 2e "---> Ti where a fine crystalline titanium is formed;

4) acts as a bipolar electrode, producing a limited amount of sodium at the ando-facing interface and at the cathode-facing interface {Ti ° ---> Ti²⁺} oxidation, and;

5) acts as a diaphragm that allows the flow of Cl ions carrying ion currents between the cathodes and the anodes without interruption, while essentially eliminating titanium ions at the interface facing the cathode, which is the result of reaction with sodium enabled by functions 1) and 4). a.

The potential difference between the anode and the cathode is still maintained so as to ensure the separation of the titanium on the cathode while simultaneously controlling the current between the anode and the crystalline layer so that the permeability of the crystalline layer is kept substantially constant. To this end, the current flow between the anode and the crystalline layer is preferably controlled such that there is so much deposition on the interface facing the anode! providing a flow of sodium sufficient to diffuse from the electrolyte surrounding the cathode toward the cathode

-Ti reaching 18 boundary surfaces²⁺ ions, and thus Ti²⁺ is substantially equilibrium between the reduction of the ions and the anodic dissolution of the Ti ° atoms at the interface facing the cathode. The apparatus of the European Patent Application EP-A-021 0961, which is already referred to, is relatively easy to replace with saturated cathodes without having to interrupt the process.

Another important aspect of the process of the present invention is the step of increasing the titanium concentration of the electrolyte to be introduced into the extraction cell 24 by dissolving the crude starting material. The dissolution process in separate cell 23 is performed by a selection cathode 30, where the selection cathode 30 is connected to a rectifier 27. Selection cathode 30 is a large metal structure immersed in the electrolyte contained in the separate cell 23. Liquid titanium tetrachloride is introduced into the electrolyte through the dosing tube 29, either externally or internally of the secretion cathode 30. Preferably, the other electrode in the separate cell 23 is a composite electrode of the present invention having titanium separators (separators 18) at the start of the operation and comprising a sodium chloride-melt bath substantially free of titanium ions within the conductive frame 3.

For example, let's start with a tired electrolyte with a titanium ion concentration of about 2% and an average valence of about 2.1. Voltage is applied between the anode and the conductive frame 3 of the composite electrode, which causes sodium, similar to the process in the extraction cell 24, to release sodium

Β • · · «4 4 • * · 4 4« φ 4 4 φ φ φ φ

Φ4ΦΦ Φ «φφ φφ

-19ki. Voltage is then applied between the secretion cathode 30 and the anode of the composite electrode to provide a titanium layer.

Titanium tetrachloride is then introduced into the selection cathode 30 in an amount that is stoichiometric to the electrical current generated on the selection cathode 30. The titanium tetrachloride is thus enriched with the desired concentration of titanium ions in the solution, generally to about 10%.

The process of dissolution is characterized by the following reactions:

TiCl₄ ---> TiCl₂ + Cl₂

TiCl₄ + 2e ---> Ti²⁺ + 4C1 "

2C1 ---> Cl₂ + 2e

It is noted in this connection that the cathodic process includes Ti³⁺ ion reaction:

2Ti³+ + 2e "---> 2TͲ⁺ where Ti³⁺ ion undergoes the following chemical reaction:

TiCl₄ + Ti²⁺ ---> 2Ti³⁺ + 4C1 ~ ¥

<img file="HUT58831A_D0001.tif" />

-20After the first step of increasing the concentration of dissolved titanium in the electrolyte, it is advantageous to reduce the mean value of the dissolved titanium ions by a softening operation, stopping the addition of titanium tetrachloride and reducing the current applied to the selective cathode. to make a further reduction by controlling the current flow between the microcrystalline layer, and continuing to reduce the trivalent titanium ion to the divalent state at the interface facing the cathode of the intermediate electrode. In the above operation, the current flowing between the anode and the conductive frame of the composite electrode is reduced to such an extent as to maintain the precipitation of sodium in a metallic form at the interface facing the anode.

In the above operation, the chlorine generated in the vicinity of the anode is removed and the sodium produced in the bipolar titanium electrode of the composite electrode reacts with the high-valence electrolyte as follows:

TiCl₃ + Na ---&gt; TiCl₂ + NaCl (III) or more:

TiCl₂ + 2Na ---&gt; Ti + 2NaCl (I) and

2TiCl₃ + Ti ---&gt; 3TiCl₂ (II) • · ·

-21It may be assumed that the high reduction efficiency of the cathodic interface is due to Ti³⁺ is due to the direct reaction of an ion with an intermediate bipolar titanium electrode, which is much more energy efficient than the deposition of metallic sodium, despite the configuration of the most resistance current path.

After the soaking operation, it is not only possible for the above reaction (II) to be carried out at 825 ° C with an average value of 2.07, but also for the {Ti³⁺ + e ---&gt; Ti²⁺} to continue the reaction, thus allowing to obtain an average value between 2.00 and 2.07 without equilibrium.

After the dissolution operation is completed and the desired average value in the electrolyte bath is reached, the connecting valve 25 is opened and kept open until the electrolytes in the separate cells 23 and the separate cells 24 are mixed homogeneously.

In one embodiment, the dissolution process can be performed without a current applied to the select cathode 30, using a composite electrode of the present invention to connect a current between the anode and the intermediate bipolar titanium electrode (i.e., conductive frame 3) match:

a) the first current component with the tetrachloride stream introduced into the electrolyte in 23 separate cells is the {2Ti³⁺ + 2e⁺ ---&gt; 2Ti²⁺} is a stoichiometrically proportional current, and

b) for selecting the other current component as a divalent metal ion, in our example, {Ti²⁺ + Ti⁰} required for selection • V · · * · 4 ·•• «9 · · · · ·

Current required for the production of a -22m degree alkali metal or alkaline earth metal, in this example sodium.

In the latter version of the method, the selection cathode 30 is optional, it is sufficient to use the injection tube 29 for injection. With regard to the dissolution process of titanium plate separator elements 18 of the composite electrode of the present invention, in the absence of the selective cathode 30, the cathodic current can be coupled to the metal wall of the melting crucible 22, thereby providing anodic dissolution of the particles.

According to a preferred embodiment of the invention, the reduction of the mean value of titanium ions dissolved in the electrolyte can be carried out by spontaneously reacting the electrolyte containing the TiCl4 and TiCl3 components having an average value of more than 2.1 with metal scrap, such as cell recycle, where the spontaneous reaction takes place without electric current as follows:

2TiCl₃ + Ti ---&gt; 3TiCl₂

The duration of the above operation is preferably from 12 to 16 hours.

In summary, the following operations are carried out in accordance with the present invention:

1) In a separate cell for receiving the titanium metal bath:

• · · ·

a) injection of titanium tetrachloride into the electrolyte bath for about 8 hours while maintaining the connection valve 25 between separate cell 23 and extraction cell 24;

b) approx. We continue to soak for 16 hours without applying electric current, where in the last two hours the connection valve 25 is opened.

2) In a separate cell for receiving an electrolyte bath containing no metal titanium:

a) injecting tetrachloride into the electrolyte bath for about 16 hours while maintaining the connection valve 25;

b) soaking for about 8 hours while applying a reduced current to the composite electrode bipolar titanium electrode, i.e. the 3 conductor frames, and opening the connection valve 25 for the last two hours.

It is possible to carry out the selection and dissolution simultaneously by providing the electrolyte flow between the separate cell 23 and the extraction cell 24 and controlling the parameters of the cathodic dissolution, in particular the addition of the halide and the current applied to the electrodes, and keeping the mean value at the required values.

Example:

Titanium is prepared essentially by means of the apparatus described in European Patent Application EP-A-021 0961, wherein the melting crucible is divided into an extraction cell and a separate cell separated from it. There are six iron cathodes in the extraction cell, each 2 m² and having five composite electrodes of the invention provided with titanium separators. A sodium chloride electrolyte bath is introduced into the composite electrode guide frame. The outer electrolyte bath contains sodium chloride and 5% titanium chloride.

At departure approximately 4000 A / m² current is applied to the cathodic surface of the composite electrode in the extraction cell and maintained for approximately one hour, then applied to the cathodes at 1500 A / m.², 500 A / m on the cathodic surface of the composite electrode² a voltage of 6.5 V between the anode and cathode of the composite electrode, and 5.5 V between its anode and its intermediate electrode (bipolar titanium electrode).

In a separate cell are arranged three selection cathodes, each of 2 m² and two composite electrodes according to the invention having a cathodic surface at the start of the process of 4000 A / m² current is maintained for one hour. The separate cell is started at the same time as the extraction cell. Subsequently, the selection cathodes are 2500 A / m² a current of 500 A / m is applied to the cathodic surface of the bipolar titanium electrode of the composite electrode²current is provided. A voltage of 6 V was applied between the anode and cathode of the composite electrode, and 5.5 V between its anode and bipolar titanium electrode, while maintaining 33.5 kg / h

-25 wt.% TiCl4 titanium chloride was added.

After 12 hours, approximately 12 kg of titanium is released on the cathodes, which after soaking are of the quality described in the table below.

SPREADSHEET

-26 ANALYSIS OF ELECTROLYTIC SELECTION OF TITANIUM Sputum Concentration (fppm-parts per million)

Szennvezőelem

Traditional value

Value realized by the process of the invention

<td>Oxygen</td><td> 650</td><td> 390</td>

<td>Nitrogen</td><td> 35</td><td> 25</td>

<td>Carbon</td><td> 85</td><td> 50</td>

<td>Chlorine</td><td> 1400</td><td> 160</td>

<td>Iron</td><td> 200</td><td> 50</td>

<td>Hydrogen</td><td> 325</td><td> 217</td>

<td>Aluminum</td><td> 100</td><td> 50</td>

<td>Vanadium</td><td> 100</td><td> 50</td>

<td>Magnesium</td><td> 100</td><td> 50</td>

<td>Nickel</td><td> 100</td><td> 50</td>

<td>Chromium</td><td> 100</td><td> 50</td>

<td>Molybdenum</td><td> 100</td><td> 50</td>

<td>You</td><td> 100</td><td> 50</td>

<td>Copper</td><td> 100</td><td> 50</td>

<td>Silicon</td><td> 100</td><td> 50</td>

<td>zirconium</td><td> 100</td><td> 50</td>

<td>Skin</td><td> 100</td><td> 30</td>

<td>Yttrium</td><td> 100</td><td> 10</td>

<td>Magnesium</td><td> 100</td><td> 10</td>

<td>Sodium</td><td> 1100</td><td> 100</td>

<td>Phosphorus</td><td> 30</td><td> 30</td>

<td>Brinnel Hardness:</td><td> 90/100</td><td> 85/86</td>

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