DE2200954A1 - Process for the preparation of ferrous, titanium-containing material - Google Patents

Description

Patent attorneys Dipl.-Ing. F. Veickmann,

Dipl.-Ing. H.Weickmann, Dipl.-Phys. Dr. K. Fincke Dipl.-Ing. F. A. Weickmann, Dipl.-Chem. B. Huber

8 MUNICH 86, DEN

PO Box 860 820

MÖHLSTRASSE 22, NUMBER 48 39 21/22

CASE NO,

BRITISH TITAN LIMITED
Haverton Hill Road, Billingham, Teesside, England

"Process for the preparation of ferrous, titanium-containing material"

The invention relates to an improved method for processing ■ ferrous and titanium-containing materials by leaching with aqueous hydrochloric acid.

A method for processing a ferrous, titanium-rich material, e.g. crushed massive ilmenite, is described in the German Patent specification .... (patent application P) described. However, the present process can be used for leaching any ferrous titanium-containing material is used, although the effect to be obtained according to the present invention is not unduly great if the iron used in the material is present your leaching is already fully present in the divalent state.

209850/0586

The invention accordingly relates to a method which consists in that one crushed iron-containing titanium-containing material with aqueous hydrochloric acid under reducing Treated conditions and then isolated a solid material that has an increased titanium content.

The mean weight particle size of the iron-containing titanium-containing material before leaching is generally below 355 / U, preferably below 100, u. Particularly satisfactory leaching can be achieved when the material has been ground to a weighted average particle size below about 4 ^ ₇ microns.

The starting material can be, for example, crushed solid ilmenite, sedimentilmenite or leucoxene, the materials having been subjected to physical separation processes, such as gravity separation processes and magnetic and / or electrostatic separation processes, in order to remove impurities different from ferrous, titanium-containing materials. Typically the starting materials contain 15 to 60 % titanium, expressed _{as TiO 2.}

The iron is preferably separated off in a one-stage leaching process by removing the comminuted iron-containing titanium content Material containing aqueous hydrochloric acid at a concentration from about 18 to 25 6ew.-5S at elevated temperature in contact is brought.

The amount of acid used is preferably in an 80 to 150% stoichiometric excess, based on the amount of acid-soluble impurities such as iron, magnesium, manganese and / or calcium contained in the material to be leached. It has been found that an amount of acid in the range from 100 to 130 % of the stoichiometric amount is particularly suitable.

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The leaching normally takes place at a temperature in the range from 80 ⁰ C to the boiling point
lying atmospheric pressure.

rich from 80 ⁰ C to the boiling point of the mixture below the

It was found that the leaching rate of the (under the leaching conditions) hydrochloric acid dissolves impurities in the ferrous titanium-containing material is increased considerably when the leaching in the presence of a Reducing agent takes place.

Examples of suitable reducing agents are iron, e.g. in Porm of scrap iron or wrought iron as well as copper, tin (II) salts, such as tin (II) chloride and sulfur dioxide. Of these Iron is both because of its cost and because it is used as ferrous chloride during the process of making the materials Can add mixture, preferably.

A sufficient amount of reducing agent is normally added to by a slight stoichiometric excess to achieve the amount required to remove the iron initially present in the ferrous titanium-containing material reduce from the trivalent state to the divalent state, although lower amounts produce beneficial results and fall within the scope of the present invention, wherein It should also be pointed out that, if desired, larger Quantities can be used.

According to the method according to the invention, it is possible to reduce the leaching time decrease to a range of 2 to 8 hours in a single step of 10 to 24 hours, with similar Iron singe be removed from the titanium-containing material.

The leaching rate can be varied in the process according to the invention can be increased even further by using your reducing agent a surface-active wetting agent is added. Showed

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Cationic surface-active agents are found to be particularly effective. Amounts in the range from 0.01 to 1% by weight , based on the amount of iron-containing, titanium-containing material, are preferably used.

The process according to the invention generally leads to a product which contains at least 70 % titanium ( _{expressed as TiO 2} ) and is preferably used to produce a product which, after drying at 105 ^° C., contains 70 to 80% by weight, based on titanium this material contains. Such products are particularly suitable as starting materials for the production of pigmented titanium dioxide according to the well-known sulfate process.

If a product with a higher titanium content is to be produced, which is to be used, for example, as a starting material for halogenation to form titanium tetrahalogenia, it can be advantageous to subject the iron-containing titanium-containing material to an additional magnetic separation step, for example using a wet separation process, before leaching to free the iron-containing titanium-containing material as much as possible from impurities, mainly from silicic acid-containing material. In this way, the method according to the invention can be obtained according to a material that after drying at 105 ⁰ C to constant weight a titanium amount (expressed as TiO ₂₎ contains greater than about 90% and a titanium content after annealing at 80O ⁰ C of at least 95 % .

The following examples are intended to explain the invention further without, however, restricting it. Examples 1 show to.5 different embodiments of the invention during Example 6 serves as a comparative example.

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example 1

Crushed massive Norwegian ilmenite was ground until only 10-15 pounds of the material had a particle size of more than 44 pounds. The material contained 45.2 % _{titanium expressed as TiO 2} and 34.6% iron expressed as Fe.

The milled material was acidified with I ² IO % of the stoichiometric amount of a 20 wt Convict state _s mixed.

The mixture was divided into a number of equal portions, which were treated as follows:

Ip Boiling at 112 ° C for two hours. After drying at 105 ^° C. to constant weight, the product contained 80.7% titanium, expressed as TiO ₂ , and 4.2 % iron, expressed as Pe. The loss on ignition at 800 ° C is 5.25 Ϊ.

2. Heat for 3 1/4 hours at 100 ⁰ C. The product contained, after drying to constant weight at 105 ⁰ C 80.2% titanium, expressed as TiO _2, and 2.9% iron, expressed as Fe. The loss on ignition at 800 ^° C. was 5.9 35.

Example 2 ,

The procedure of Example 1 was repeated except that the Mix during

(a) 5 hours and

(b) 6 hours - *

heated to 10O ⁰ C, wherein in (a) only 2/3 and (b) only 1/6

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the amount of tin (II) chloride used in Example 1 was added became.

The product of (a) contained 80.8 % titanium, expressed as TiO ₂ , and 2.4 % iron, expressed as Pe. The loss on ignition at 800 ^° C. was 5.9 %,

The product of (b) contained 72.5 % titanium, expressed as TiO ₂ , and 10.2 % iron, expressed as Fe. The loss on ignition at 80O ⁰ C was 3.8 Ji.

example

Portions of the crushed and ground Norwegian ilmenite described in Example 1 were mixed with the different amounts of 20% aqueous hydrochloric acid given below and with a sufficient amount of tin (II) chloride that was necessary to convert the oleene present in the trivalent state into the divalent To reduce the state, added, whereupon the mixtures were heated ^{to 100 0 C during the specified times.} The titanium content of the dried products is summarized in the following table:

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HCl content of the
mixture
(-1 of the stoichiometrically required amount)

- 120

- 110

100
Λ 90
80

Heating time
(Hours.) titanium
salary
(as TiO ₂ )
% iron
salary
(as Fe)
% Annealing
lust at
800 ⁰ C
% 4th 81.5 2.6 "6.1 - 4th 79.1 5.0 5.1 5 76.5 7.3 M. 8th 72, 4 9.2 M. 8th 69.5 12.1 3.1

At s ρ i el 4. -

2 kg of the comminuted and ground described in Example 1 Norwegian Ilmehits were given a 1 * 10 jSigen stoichiometric Excess of 20% aqueous hydrochloric acid and mixed with 700 g of scrap iron and heated to 100 ° C for 6 hours.

The product contained, after drying at 105 ⁰ C 80.2% titanium, expressed as TiO _2, and showed a Glühver-loss at 800 ° C of 4.6 f. ■

This procedure was repeated, but using a wrought iron rod with a diameter of 2.54 cm, which corresponded to 190 g of iron, was used and the heating continued for 5 hours was leading.

The product in this case contained $ 77.6 titanium, expressed as TiO ₂ . The GlQhverlust at 800 ⁰ C was 4.8%,

example

200 g portions of Norwegian ilmenite were ground until only 10 to 15 % of the material had a grain size greater than 44 / u. The material was then leached with 7 ^ 7 ml 20.24 $ HCl (l4o% of the stoichiometrically required amount) at 100 ⁰ C in the presence of copper chips during the indicated times in the following table. The results obtained are also summarized in the following table:

Amount of copper Leaching time Titanium content Loss on ignition at 80O ⁰ C (g) (hours) (as TiO ₀ )

0.5 5 58.3 0.6 1.5 5 63.7 1.2 2.5 5 67.9 2.5 3.5 5 74.5 3.7 5.0 5 80.7 6.0 5.0 7th 81.3 5.5 7.5 4th 78.3 5.1 10.0 3 1/2 82.3 6.8

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Example 6

The Norwegian ilmenite described in the previous examples was mixed with 1 * 10% of the required stoichiometric amount of hydrochloric acid, but without the addition of a reducing agent, whereupon the mixture was mixed for 2 *? Was heated to 100 ° C for hours

The final product contained 8l _s 9% of titanium, expressed as TIOP and showed a loss on ignition at 800 ° C of 4.6% "

During the leaching, the iron content of the leaching liquid became determined and the results obtained are summarized in the following table; ,

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Leach time
CStd,) Iron content (g / l)
the leaching liquid
(as Pe) 1 23.2 2 24.9 3 25.8 4th 35.0 5 47.8 6th 57.7 7th 65.5 8th 70.8 9 75.3 10 79.0 . 11 81.8 12th 84.3 1} 86.0 14th 87.4 15th 88.2 16 88.7, 17th 88.8 18th 88.8 19th 89.6 20th 90.4 21 91.0 22nd 91.0 23 91.8 24 94.6

Example 6 was not "according to the method of the invention carried out and is only used for comparison purposes.

209850/0586

Claims (18)

- .11 - PATENT CLAIMS: 1, "A method for treating iron-containing titaniferous material, characterized _s that leaching the crushed material with aqueous hydrochloric acid under reducing conditions, and then wins a solid material having an increased titanium content. 2. The method according to claim 1, characterized in that the mean weighted particle size of the comminuted ferrous titanium-containing material less than 355 / U amounts to. 3. The method according to claim 2, characterized in that the mean weighted particle size is less than 100, u is. H. The method according to claim 3 »characterized in that the mean weighted particle size is less than Hk. u is. 5. The method according to any one of the preceding claims, characterized in that the aqueous hydrochloric acid has a concentration in the range of 18 to 25 wt. 6. The method according to any one of the preceding claims, characterized in that the amount of hydrochloric acid used 80 to 150 % of the stoichioiaetriseh required 209850/0586 Amount based on that in the ferrous, titanium-containing material any acid-soluble impurities present. 7. The method according to claim 6, characterized in that that the amount of hydrochloric acid is present in a 100 to 130 #igeh stoichiometric excess. 8. * The method according to any one of the preceding claims, characterized in that the leaching is carried out at a temperature in the range from 80 ⁰ C to the boiling point of the mixture under the prevailing atmospheric pressure. 9. The method according to any one of the preceding claims, characterized in that the reducing conditions by the addition of iron to the leaching vessel. 10. Method according to one of the preceding claims, characterized in that the reducing conditions are due to the presence of copper, tin (II) salts and / or sulfur dioxide be brought about. 11. The method according to any one of the preceding claims, characterized in that the reducing conditions caused that the reducing agent is present in an amount in excess of the stoichiometric Amount used to reduce the amount originally contained in the iron-containing titanium-containing material in the trivalent state existing iron in the divalent state is required, corresponds. 12. The method according to one of the preceding claims characterized in that the ferrous titanium-containing material is leached for a period of 2 to B hours. 209850 / 058b 13. The method according to one of the * preceding claims, characterized in that the leaching is carried out in the presence of a surface-active wetting agent. I ¹ I. The method according to claim 13, characterized in that the wetting agent is a cationic surface-active agent. 15. The method according to claim 13 or I ¹ I, characterized in that the wetting agent is present in a concentration in the range from 0.01 to 1 weight percent, based on the amount of iron-containing titanium-containing material. 16. The method according to any one of the preceding claims, characterized in that the leaching is carried out, until a product is obtained, which after drying at 105 ⁰ C between 70 and 80 wt -.% Of titanium, expressed as TiO ₀ contains. 17. The method according to any one of claims 1 to 15, characterized in that the iron-containing titanium-containing material is subjected to a magnetic separation process before leaching and is then leached under such conditions that the product after drying at 105 ⁰ C is more than 90 % titanium , expressed as TiO ₂ . 18. Recycled iron-containing titanium-containing material, obtained according to a method according to one of the preceding Expectations, 209850 '/ 0586