DE1024938B - Process for the production of titanium salt solutions from concentrates containing titanium - Google Patents

Description

Process for the production of titanium salt solutions from concentrates containing titanium In the known digestion process of titanium-containing concentrates or ores for the purpose Production of. Titanium, oxides, pigments and the like become the starting material, viz the ore or concentrate, first ground and digested with sulfuric acid. This creates a firm cake made of water-soluble titanium and iron sulfate, the is then dissolved in water. The resulting aqueous solution is required if necessary with a reducing agent, e.g. B. with metallic iron., Treated to the entire To convert iron into ferrous iron; however, at the same time it becomes a smaller one Share of titanium in the amount of 1 to 2% converted into trivalent titanium. The on solution obtained in this way is then purified by clarification in a manner known per se.

In order to carry out the clarification, it is known to use the solution with a Sulfide, e.g. B. sodium hydro-sulfide, Ainononiuinsulfid o, d. Like. To treat. That Sulphide reacts with the antimony already present in the solution, whereby a flaky one Precipitation of antimony sulfide is obtained, which is the greater part of the smaller insoluble impurities and suspended solids the floor. a sedimentation tank. From the clear, above the flocculation Solution can. high quality titanium oxide and titanium pigment can be obtained.

Since antimony is generally not present in sufficient quantities in the ore its addition is required. The antimony is usually added by that an acid-soluble antimony compound, e.g. B. the trisulfide, trioxide or that Pentoxide or an ore containing antimony, such as stibnite, directly to the titanium containing Ore is added at the beginning of the process. The antimony compound becomes at the same time digested with the titanium-containing ore and forms soluble antimony sulphate, the together with the ore constituents during the subsequent dissolution in water solves. In a modification of this method, the antimony can be in acid-soluble form the aqueous solution are added. After the digestion cake is dissolved in water been. is. Of course, this method is less effective for those that are difficult to dissolve. Antimo: n connections, so that one behaves-. Ice-like insoluble antimony material, such as stibnite ore adds to the digestion in order to achieve a solution of the antitnon components.

When adding the antimony to the ore or to the subsequently formed aqueous solution, difficulties arise in many cases. insofar as the antimony is partially unsuitable for the formation of the required antimony sulfide precipitate; in addition, the amount of antimony which is effective in forming a clarifying agent varies The extent of the antimony sulphide precipitation is necessary, depending on the ore used for reasons that have not yet been clarified ..

The invention provides an improvement on these known methods for the treatment of titanium-containing ores and provides a more economical method to digest the ores and to clarify the solutions produced from them, whereby the antimony parts used in the clarification of the titanium-containing solutions are better utilized will.

The method according to the invention for the treatment of titanium-containing ores, Concentrates or slag consists of a series of measures, whereby the Starting material is first digested with sulfuric acid, the reaction mass is then dissolved in an aqueous solution, whereupon the aqueous solution according to the invention is purified from sulphide components. 1n d, the solution thus obtained is subsequently an antimony compound is dissolved and then a sulfide is added by the antimony in Form of. Antimony sulfide is precipitated.

Procedures where. titanium-containing ores dissolved or digested and in which the resulting reaction mass is absorbed in water and that Ferriedsen and, to a lesser extent, the titanium in the resulting solution are: are generally known and do not experience any special in the context of the invention Amendments.

The purification according to the invention of the system from sulfides after solution The reactive mass in water can be done in different ways. The easiest and cheapest option, however, is that Air or a inert gas is bubbled through the solution long enough to remove virtually all of the sulfide to remove, which are normally present as hydrogen sulfide. Because the solution is relatively strongly acidic, the sulfur, water, and substance can be removed easily and quickly in front of you; usually a few minutes lasting, moderately results strong ventilation for the desired success.

Other, usually less favorable, methods of removing the Sulphide components are equally effective. For example, it was found dali the sulphide proportions before the reduction of Ferrieis ° as to Ferroeisen on the muddy undissolved residue are bound, which is mainly from insoluble gait Od. The like. And small proportions of non-digested ore exists. This residue can e.g. Removed by filtration before reducing the solution; in in this case no hydrogen sulfide is formed during the reduction. Under Under these conditions, the antimony can be used in any process stage after filtration of the Solution are added, if necessary even before reducing the solution.

After the sulphide components have been precipitated,. the antimony content without difficulty Can be added in any acid-soluble form; because of economical reasons is preferable to Antimony Trio-xvd. After dissolving the antimony, the sulfide. B. Sodium sulfide or ammonium sulfide, added, whereupon a voluminous, easily settling flaky precipitate arises, as required for effective clarification is. Albeit the entire mechanism of reaction which comes into effect in the practice of the invention is not fully clear, it can be assumed that the open-mindedAusgan: gs.materials almost always contain sulphide components to varying degrees. In the reduction In the solution after the digestion, these sulphide components become hydrogen sulphide converted. The appearance of. Hydrogen sulfide seems timed with the first. Trivalent titanium appears after the reduction of practically all of the ferrous iron to collapse into ferrous iron. This hydrogen sulphide reacts immediately with your existing antimony to antimony sulfide. The anti-ion sulfide thus formed however, it is not in an effective form as it is not the one to clarify either required form of flaky precipitate forms or when such a precipitate is formed, this is divided and when transitioning from your decomposition vessel in the clarification tank becomes ineffective for the clarification.

If no antimony, start .. of the process in the digestion material is present, but it is after dissolving the digestion cake in water and afterwards Reduction of the iron content is drawn out, sulfur wa.s: se.rstcff is formed, which remains in the solution until the addition of antimony, with - i then antimony sulfide is formed. This an.tinic sulfide, however, is made up of the same ones given above Not suitable for reasons of clarification.

If so, the hydrogen sulfide, on the other hand, before adding the antimony is removed, nothing occurs until the addition of the sulfides: Precipitation of. Antimony sulfide a. There. the sulphide-forming agents usually directly in the septic tank be admitted. the flaky precipitation has no possibility of breaking up and therefore cannot take effect; rather it is done with a minimal effort Antimony achieved a good clarification. The following examples serve further Explanation of the invention.

Example 1 22.5 tons of dichite ore, 38.25 tons of 93% sulfuric acid and 2.06 t water was used in the usual way for the purpose of forming one of titanium and iron sulfate existing digestion cake reacted. This cake was in 52.8 t water and the iron contained in the solution by adding iron scrap reduced to ferrous iron until an analysis of the solution shows the presence of 3.0 - / l trivalent titanium, calculated as Ti O. The solution was then from Sch: wefel, hydrogenated by passing through the bottom of the vessel: during 2 hours Air was introduced in an amount of about 3.5-1 in / min. With the termination of Ventilation was the hydrogen sulfide, as a test of finite lead acetate paper showed practically removed. The solution was again with regard to the reduced titanium content analyzed; it was now 3.0 g / 1 trivalent titanium, calculated as Ti O .., available. In the solution pretreated in this way, 6.8 kg of #luitirnontrioxyd were then added dissolved and the solution is pumped into a settling tank serving for clarification, the was equipped with means for introducing a 1Tatriuinliydrosulfidlösung by the 0.1-108 in 3 of a solution containing 11 g / 1 sodium trium hydrosulfide. A voluminous, flaky precipitate of antimony sulfide resulted. The precipitation quickly settled on the vessel i) o, the off and in this the in. the solution suspended solids, so there was a clear liquid above the precipitate remained.

For comparison purposes, the above procedure was repeated, wherein the purification of the system from hydrogen sulfide by blowing with air is omitted became. The amount of antimony sulfide formed on subsequent clarification was approximately 6% of that amount which was formed on removal of the hydrogen sulphide. Satisfactory clarification of the titanium sulfate solution was not achieved.

Based on the above comparative experiment, the Procedure. repeated again, with 27.2 kg, so four-anal as much antimony trioxide as were used before. After adding natritinilydrostilfiei l; egg of the subsequent Clarification, the amount of antimonsuli precipitate formed was approximately the same as that those with the lower concentration of amino acids before removal of the hydrogen sulfide was achieved; the Lö, sunig was cleared in a satisfactory manner. Example 2 That Procedure. according to Example 1, # was repeated with the exception that the reduction four digestion solution not with scrap iron, but dry by adding 4.2 t reduced ilenite ore containing 24% metallic iron.

The solution containing the reduced dichitol was then vented with air Treated according to Example 1 until the hydrogen sulfide is practically complete was removed. An analysis that has now been carried out showed that the solution was 3 g / 1 trivalent Titanium, calculated as Ti O ", contains. Then 6.8 hg of antimony trioxide were in the solution dissolved and the solution pumped into a clarifier and clarified according to Example 1, where 0, -108 m3 of a solution containing 11 g / 1 \ atrium liydrosulfide is used became.. The results were practically the same as in Example 1.

Comparative tests were carried out by placing dry before dispensing reduced ilmenite from the titanium-iron-sulfate solution produced from the ore a sample was taken. This sample was reduced with the same. Youit reduced, but without aeration of the solution. A further .--, sample was also made Taken from the above batch after aeration has been carried out. The non-ventilated Sample required four times as much antimony than the ventilated sample for the same volume the clarification. Example 3 The procedure of Example 1 was repeated with the exception that the solution was filtered before reducing the ferrous iron components. It wasn't Ventilation applied and no formation of hydrogen sulfide observed. the reduced solution was clarified according to Example 1 and showed practically the same Results as in example 1. Example 4 The procedure according to example 3 was repeated with the exception that after filtration and before reduction, antimony is added and in the solution has been dissolved. Here, too, the results were practically the same as in example 1.

The method according to the invention leads to substantial savings in the treatment of ores containing titanium by using antimony as a clarifying agent. The amount of savings depends to some extent on: The amount of those present in the system Sulphide contamination: g and from the required. Degree of completeness of the Clarification. Most if: not all ores containing titanium contain small amounts of sulphide; In addition, sulphide contamination is often carried out with your iron scrap or another. reducing agents used to reduce the digestion solution fed. All of these sulfides consume equivalent amounts. of valuable antimony; when the method according to the invention is used, such consumption of antimony occurs prevented; the savings achieved are considerable.

To remove the sulphide components from the digestion solution before addition of antimony, other methods can also be used. The solution can e.g. B. after the Reduction for the purpose of removing the hydrogen sulfide in a Vahuum.gefäß od. like. be put under negative pressure., or the sulfide components can with other, cheaper precipitants than antimony, e.g. B. with lead, are precipitated :. the However, method of removing the sulfides by aeration is because of their convenience and economy by far.

Claims (3)

PATEN TANSPRCCHi? 1. Procedure for obtaining. Titanium salt solutions from titanium-containing. Concentrates, characterized in that the following measures are carried out one after the other: a) The ore is digested in a known `` '' ice with sulfuric acid and the reaction mass obtained is dissolved in an aqueous solution. b) The aqueous solution is purified from sulfide components. c) An antimony compound is then dissolved in the solution in a manner known per se. d) The antimony compound is then precipitated in the form of antimony sulfide by adding a sulfide to the solution in a manner known per se. 2. The method according to claim 1, characterized in that there, ß the aqueous solution for the purpose of removing the contained in the form of hydrogen sulfide Sulphide components are subjected to aeration, preferably by blowing with air, the iron contained in the solution being present as ferrous iron during the aeration. 3. The method according to claim 1, characterized in that for the purpose of cleaning the solution of, sulfide fractions of the solid residue before reduction of the ferrous iron fractions present in it removed from the solution.