DE1081673B - Process for the production of titanium - Google Patents

Description

GERMAN

The present invention relates to an improved method for making titanium.

In one process for producing titanium, titanium tetrachloride is mixed with metallic sodium in an inert atmosphere, and a mixture is formed, which is essentially titanium metal and contains sodium chloride. A certain amount of not can also be present in the reaction mixture reacted sodium or titanium subchlorides should be present, which, among other things, depends on the accuracy of the conditions depends under which the reaction is carried out. To achieve high yields the reaction is preferably carried out at a temperature which is above the melting point of Sodium chloride and below the boiling point of sodium; temperatures of the The order of magnitude of 850 ° C has been found to be particularly suitable.

After the reaction is complete and the products at room temperature in an inert atmosphere have cooled down, a solid mass remains from which the titanium is to be isolated. In a procedure which has hitherto been used for this purpose, the solid mass is broken and then preferably in the presence of a small amount of a mineral acid Treated appropriately to remove the sodium chloride and other solubles by leaching dissolve with an aqueous solution. After careful washing, the titanium metal is then in dried in an inert atmosphere and finally melted in an electric arc furnace.

However, leaching the products with an aqueous solution has certain disadvantages. Initially requires this procedure involves the use of a very large amount of water. According to a stoichiometric Invoice is made on every ton of titanium that is made metallic through the implementation of titanium tetrahalloride nitride Sodium is generated, at the same time about 5 tons of sodium chloride are formed, for which about 15 tons of water are required are to resolve this at the saturation point. Hence it follows that a very considerable one Amount of water required to perform the caustic treatment "; as a result, are time-consuming and cumbersome treatments required to get the bigger out of the reaction mixture Extract portion of sodium chloride.

It was also observed that traces of impurities in the titanium are entered, whereby the quality of the actual end product is considerable Dimensions is worsened. '

It has now been found that a considerable proportion of the metallic titanium contained in the solidified mass, which by cooling the environment

Process for the production of titanium

Applicant:

Imperial Chemical Industries Limited,
London

. Representative:

Dipl.-Ing. A. Bohr, Dipl.-Ing. H. Bohr, Munich 5, · and Dr.-Ing. H. Fincke, Berlin-Lichterfelde, Drakestr. 51, Patent attorneys

Claimed priority:

Great Britain 7 December 1955

and November 28, 1956

James Crosby Smart, Widnes, Lancashire

(Great Britain),
• has been named as the inventor

Settlement products obtained from titanium tetrahaloride and sodium can be separated off without it it is necessary to bring the titanium into contact with water or another caustic liquid.

The method forming the subject of the invention is based on the surprising observation, that when the solid mass contained in the reaction product is crushed to a corresponding fineness the metallic titanium will isolate into a fraction of the crushed or contaminated product let which can be easily separated from the rest of the part by mechanical means and which are then put into treated accordingly to obtain high quality pure titanium, this treatment by an aqueous or non-aqueous alkali treatment, vacuum distillation or direct melting he follows.

According to the invention, the method for separating titanium from the reaction products of _ Titanium tetra chloride and sodium characterized in that the reaction product is reduced to a particle size of a maximum of 6.3 mm is comminuted, with a portion enriched in titanium from this by mechanical means Agent deposited and the titanium is isolated from the so deposited portion. Appropriately the comminution takes place -by breaking, whereby the whole amount of the product through a sieve with a mesh size between 6.3 and 0.5 mm and preferably

<HW'509ß52

point out such a mesh size of 3.2 mm: goes through.

One method of separating the titanium is by sieving the mixture so that the Part containing larger grain size, which the. contains larger part of the titanium is isolated. It however, other methods can also be used, e.g. B. Wind direction, electromagnetic separation, Setting treatment or stove work.

A particularly suitable and particularly expedient method to carry out a separation, consists in that the crushed mixture is passed three times through a mill which is equipped with a sieve plate a mesh size between 0.29 and 0.104 mm is provided, the mass after each grinding treatment is sieved with a sieve with a mesh size of 0.15 mm to separate the fine components. It has been shown that the powder retained on the sieve with a mesh size of 0.15 mm Contains 73.3% titanium metal and thereby 85.3% of the total metal is recovered. It continued to be found that this, sieve treatment is significantly simplified when the process is at low relative Moisture is carried out, e.g. B. at less than 50% relative humidity.

It has been found that it is not practical to have any other than partial separation carry out the constituents of the reaction product through this sieve treatment stage.

After such a partial separation of the titanium is carried out by the method described above has been, the final stage of the process is that of the separated portions pure titanium is isolated. It was found that from the titanium-rich portion, a pure titanium of high Quality can be produced by the well-known caustic treatments or by vacuum distillation. It However, it was also found that with direct arc melting of the titanium-rich portion on the Inter-caustic treatment can be dispensed with and a purer product can be obtained as a result.

In order to make the process economical in practice, however, it is expedient to use the sodium chloride-free Share not to be discarded. This proportion contains about 9% of the titanium metal, and advantageously almost all of this metal is extracted. It has been found to be the most economical method The recovery consists in first removing the material by air separation or electrostatic Deposition is enriched; by this method, the proportion of titanium in the sodium chloride can be high Material can be increased up to 40% titanium. The titanium can then be extracted from the enriched mixture isolated by any of the conventional methods, preferably by aqueous alkali treatment will.

It should be noted that with this limited caustic treatment, a relatively minor one The amount of water required is compared to that which is necessary to get the sodium chloride out of the actual mass of the reaction product to be deposited. The advantage of the subject invention forming process consists in that it by Introducing the various specified work steps is possible, titanium with lower hydrogen and to maintain oxygen levels than is possible with the usual caustic treatments; during execution this procedure requires less time and cost, and it can be done with a lot less Amount of water to be worked. 7 "

In the following example, the method is explained in more detail without being restricted to it.

example

Titanium tetrachloride and sodium were reacted with each other in an inert atmosphere to form a mixture of titanium metal and molten sodium chloride. The mixture was allowed to cool. After the reaction vessel was cooled and emptied, the reaction product became too crushed into small pieces. A number of these pieces have since been removed by hand picking they apparently consisted almost entirely of salt and contained practically no titanium.

The mixture thus concentrated was then ground in a mill which was provided with a sieve plate of 3.2 mm. The fine portion of the ground material contained 33% titanium. This powder was then passed three times through a mill equipped with a sieve plate with a mesh size of 1.6 mm, and after each grinding treatment the fines which passed through a sieve with a mesh size of 0.15 mm were sieved off. The larger fraction, which was retained on the sieve with a mesh size of 0.15 mm, contained 73.3% titanium metal, which corresponds to a yield of 85.3% of the starting metal. The powder was then pressed into bars under a pressure of 3000 kg / cm ² , from which consumable electrodes for an electric arc furnace, from which solid titanium with a Vickers hardness of 120 and a hydrogen content of 0.001% was produced. 15% of the metal contained in the starting sample had accumulated in the fines, which contained 8.8% titanium. This titanium content was enriched by air sifting, whereby a product was obtained which had 95% of the metal content of the fine in the form of a titanium salt mixture containing 40% metal. The titanium metal was then separated in the form of a powder by an aqueous alkali treatment and melted in the electric arc furnace, whereby metallic titanium having a Vickers hardness of 135 and a hydrogen content of 0.003% was obtained.

A sample of the starting melt was ground in a mill equipped with a 3.2 mm sieve and was passed through Aqueous alkali treatment worked up. The titanium obtained after arc melting had a Vickers hardness of 129 and a hydrogen content of 0.004%.

Claims (5)

PATENT CLAIMS: 1. Process for, production of titanium by reducing titanium tetrachloride with sodium, wherein the reaction product consisting essentially of titanium and sodium chloride to a Particle size of at most 6.3 mm is crushed and the titanium from the treated Reaction product is separated, characterized in that the pretreated reaction product by mechanical means, e.g. B .. through Sieving, air sifting, electromagnetic separation, settling treatment or stove work, in a titanium-rich portion of larger particle size and a sodium chloride-rich portion smaller particle size is separated and: that the titanium-rich portion in a manner known per se preferably by arc melting or z. B / ■ further processed by leaching or vacuum distillation and that the titanium is thereby separated from the fraction of smaller particle size is that this portion is first processed by air sifting or electrostatic separation and then the titanium from the resulting enriched mixture according to a known method Procedure, e.g. B. is isolated by an aqueous alkali treatment. 2. The method according to claim 1, characterized in that the reaction product is broken so far that it is passed through a sieve with a mesh size between 6.3 and 0.5 mm, preferably one with a mesh size of 3.2 mm. 3. The method according to any one of the preceding claims, characterized in that the reaction product after comminution through a sieve with a mesh size between 0.29 and 0.104 mm is sieved to obtain a titanium-rich fraction Separate from a sodium chloride-rich portion, with the titanium-rich portion on the sieve remains behind. 4. The method according to claim 3, characterized in that the reaction product by a Sieve with a mesh size of 0.15 mm is sieved. 5. The method according to any one of the preceding claims, characterized in that the sieve treatment is carried out at a relative humidity of less than 50%. Considered publications:
German patent specification No. 658 995. © 009 5W352 5.60