EP0100865B1 - Procédé pour la production d'une solution hydrolysable de titanylsulfate - Google Patents

Procédé pour la production d'une solution hydrolysable de titanylsulfate Download PDF

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Publication number
EP0100865B1
EP0100865B1 EP83106581A EP83106581A EP0100865B1 EP 0100865 B1 EP0100865 B1 EP 0100865B1 EP 83106581 A EP83106581 A EP 83106581A EP 83106581 A EP83106581 A EP 83106581A EP 0100865 B1 EP0100865 B1 EP 0100865B1
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EP
European Patent Office
Prior art keywords
titanium
iii
raw materials
process according
particle size
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Expired
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EP83106581A
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German (de)
English (en)
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EP0100865A1 (fr
Inventor
Klaus Dr. Köhler
Günther Dr. Lailach
Bernd Dr. Holle
Walter Dr. Gutsche
Peter Dr. Panek
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Bayer AG
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Bayer AG
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    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B34/00—Obtaining refractory metals
    • C22B34/10—Obtaining titanium, zirconium or hafnium
    • C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08
    • C22B34/1236—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by wet processes, e.g. by leaching
    • C22B34/124—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by wet processes, e.g. by leaching using acidic solutions or liquors
    • C22B34/125—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08 obtaining titanium or titanium compounds from ores or scrap by wet processes, e.g. by leaching using acidic solutions or liquors containing a sulfur ion as active agent
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22B—PRODUCTION AND REFINING OF METALS; PRETREATMENT OF RAW MATERIALS
    • C22B34/00—Obtaining refractory metals
    • C22B34/10—Obtaining titanium, zirconium or hafnium
    • C22B34/12—Obtaining titanium or titanium compounds from ores or scrap by metallurgical processing; preparation of titanium compounds from other titanium compounds see C01G23/00 - C01G23/08

Definitions

  • the present invention relates to a method for producing a hydrolyzable titanyl sulfate solution from mixtures of previously ground llmenite- and titanium- (III) -containing raw materials, in particular titanium (111) -containing slags, digestion of the raw material mixtures with sulfuric acid and dissolving of the solidified reaction masses in an aqueous solvent.
  • the reaction rate or the turnover per unit of time is essentially determined by the size of the surface of the solid.
  • the reaction rate or the turnover per unit of time is essentially determined by the size of the surface of the solid.
  • the surface of a given amount of solids is largely determined by the size of the particles. The smaller the individual particles, the larger the surface available for a heterogeneous reaction.
  • An increase in the surface area of solids is generally achieved by grinding processes.
  • the solids to be digested are usually ground to a specific fineness in grinding units such as drum ball mills, ball vibrating mills, pendulum mills or roller mill mills, which are equipped with suitable classifying devices.
  • the energetic efficiency of such dry grinding is known to be very poor and efforts have not been lacking in the past to improve this situation.
  • the grinding of titanium ores, in particular ilmenite can advantageously be carried out in the presence of naphthenic acids.
  • the present invention thus relates to a process for preparing a hydrolyzable titanyl sulfate solution from mixtures of previously ground ilmenite and titanium (III) -containing raw materials, in particular titanium (III) -containing slags, digestion of the raw material mixtures with sulfuric acid and dissolving of the solidified reaction masses in an aqueous solvent, the titanium (III) -containing raw materials being ground in the presence of organic auxiliaries from the group of the alkanolamines and / or polysiloxanes.
  • the auxiliary agent or additives are added to the slag for grinding in amounts of 0.002 to 0.5% by weight, preferably 0.005 to 0.15% by weight, even small amounts giving a clear economic advantage.
  • the addition can take place before the actual grinding of the slag, but also by means of suitable feeding devices into the mill during the grinding process.
  • a procedure is preferred in which the auxiliary is added to the slag before the drying preceding the grinding. It is cheap, but does not constitute a limitation of the inventive concept, to add the auxiliaries in the form of aqueous solutions and / or emulsions, because this results in the better distribution of the adjuvant the total surface of the regrind is conveyed.
  • the auxiliary can be added in mixing drums, but also, for example, by spraying devices. In principle, all methods are suitable which ensure a uniform distribution of the auxiliary over the total volume of the material to be ground.
  • the alkanolamine is a monoisopropanolamine and / or a diisopropanolamine and / or triisopropanolamine.
  • the polysiloxanes used can have a chain, branched or cyclic structure and can contain alkyl, aryl and / or cycloalkyl radicals and / or hydroxyl radicals. Due to economic considerations, polydimethylsiloxanes are particularly suitable.
  • the method according to the invention can in principle be applied to the most varied designs of dry grinding units, such as, for example, ball drum, ball oscillating, pendulum or roller roller mills.
  • dry grinding units such as, for example, ball drum, ball oscillating, pendulum or roller roller mills.
  • a significant improvement in the grinding is achieved, which is either expressed in an increased fine particle size of the ground material with the same grinding output used or, if the desired fine particle size is sought, leads to a reduction in the grinding time or, in other words, to an increase in throughput of the ground material through the mill. This results in considerable energy savings in the grinding energy to be used.
  • the raw materials are ground in the grinding units described above, which are equipped with suitable classifying devices in order to achieve a targeted adjustment of the grain size distribution of the ground material.
  • the grain sizes can also be generated using pendulum mills or roller mills. If necessary, the setting of a certain particle size of the ores intended for the sulfuric acid digestion can also be carried out by means of screening devices, such as Vibrating screens or air jet screens are used.
  • the additives according to the invention enable the grain sizes to be obtained to be obtained economically (see also FIG. 5).
  • ore mixtures with the defined grain sizes are characterized in that the ore components used in the raw material mixture reach the maximum reaction temperature in the same time after starting the digestion reaction and the mixture solidifies uniformly when this temperature is reached.
  • Such ore mixtures can be easily digested with sulfuric acid even in discontinuous batch operation.
  • the titanium raw materials specified in Tab. 1 are brought to a uniform grain size ⁇ 1 mm via a sieve, sprayed with the auxiliaries listed in Tab. 1, optionally dried at 150 ° C and in 300 g portions in steel cylindrical grinding bowls (volume 1000 ml) filled, 1800 g of steel balls of 15 mm in diameter were added and the grinding bowls were rotated on a roller block for 8 hours. After the grinding procedure had been completed, the percentage of different fractions was determined by sieve analysis and the particle size distribution was determined in this way. The results are recorded in Table 1 and make it clear that the addition of the auxiliaries according to the invention leads to an increased fine particle size of the ground material.
  • the titanium (III) -containing slag B which is described in more detail in Table 2, is brought to a uniform particle size of ⁇ 1 mm using a sieve, with varying amounts of a 60% strength aqueous solution of a mixture of 1 part by weight. Monoisopropanolamine and 1 part by weight. Sprayed diisopropanolamine and dried at 150 ° C.
  • the slag prepared in this way was filled in quantities of 300 g into steel grinding bowls (volume 1000 ml), 1800 g of steel balls with a diameter of 15 mm were added and subjected to vibratory grinding on a vibration device (“Vibraton”, from Siebtechnik, Mühlheim-Speldorf).
  • Vibraton from Siebtechnik, Mühlheim-Speldorf
  • the results of these series of tests show that, with the same grinding time, the addition of the auxiliary agent increases the fine particle size or that the fine particle size, which is achieved after 3 hours of grinding time without auxiliary agents, is present in suitable amounts after 2 hours of grinding time when the grinding aid is used . This means that the grinding time is reduced by 33%.
  • the slag characterized in this way was ground in two rows without or with the addition of 0.1% of a 1: 1 mixture of mono- and diisopropanolamine for different times in a vibrating ball mill in accordance with Example 17-28.
  • the results are shown graphically in FIG. 2. They show that with the grinding aid according to the invention, a fine particle size of 100% 40 gm is achieved after 2 hours (A), while without the addition of auxiliary agents, even after 4 hours' residence time (h) in the mill, no adequate fine particle size is achieved (B).
  • Equal amounts of a slag B from Examples 17-28 were reacted in a suitable apparatus for the purpose of digestion with an 88% sulfuric acid by diluting a 96% acid with water according to known methods and the SO z emitted during the digestion reaction Quantity determined analytically.
  • Experiments 34 and 35 serve as reference experiments and were carried out without the addition of auxiliary materials.
  • Experiments 36 and 37 were carried out with the addition of 0.1% (based on ore) of the auxiliary according to the invention from Examples 17-28.
  • Experiments 38 and 39 were carried out with the addition of 0.1% (based on ore) naphthenic acid in accordance with the teaching of US Pat. No. 2,437,164. Table 4 shows the results of this series of tests.
  • Examples 36 and 37 behave with the aid according to the invention with respect to SO z emission and foam formation like Reference Examples 34 and 35.
  • a slag from Examples 29-33 is reacted in a suitable apparatus with an 88% sulfuric acid by diluting oleum (25% free SO 3 ) with a 65% sulfuric acid.
  • Test 44 was carried out with the addition of 0.1% mono- / diisopropanolamine (1: 1), test 45 with 0.1% naphthenic acid. After manufacture, the reaction mass was aged for 5 hours at 180 ° C., dissolved in water and the dissolved proportion of the TiO 2 used and the content of trivalent titanium in the solution were determined.
  • the digestion product remaining in the vessel was aged in a drying cabinet at 180 ° C. for 5 hours and then ge by adding 800 ml of water at 70 ° C. in the course of 4 hours while passing 100 l of air per hour solves. There were 95.0% of the Ti0 2 used in the solution. The average Ti (III) content of the solution was 2.2% of the dissolved TiO 2 .
  • the example shows that the digestion reaction when using fine-particle ilmenite (expressed as a percentage ⁇ 40 ⁇ m) together with larger-scale slags undesirably with formation of two temporally far apart maxima of the reaction temperature, a large delay in the time until the reaction mass is finally solidified and an undesirable one Pressure increase in the decomposition vessel takes place.
  • Example 46 The test procedure corresponded in all points to that of Example 46, with the difference that the ilmenite used had a grain size of between 75 ⁇ m and 90 ⁇ m to 100%. 4 shows the temperature over time. In contrast to Example 46, there is no second temperature maximum. The experiment was carried out without spontaneous pressure development in the digestion tank. After appropriate separation and dissolution of the reaction mass in water, 94.8% of the Ti0 2 used was in solution. The average Ti (III) content of the solution was determined to be 7.2% of the dissolved TiO 2 .
  • the example shows that the use of relatively coarsely divided ilmenite together with slags enables problem-free digestion behavior in discontinuous operation.
  • Example 46 In the apparatus of Example 46, 315.5 g of a concentrated sulfuric acid with an H 2 SO 4 content of 65.0% and 400 g of a ternary raw material mixture consisting of 66.8 g to a grain size of 87.6% ⁇ were placed 40 ⁇ m ground ilmenite, which has a TiO 2 content of 59.6%, an iron content of 24.4% and an iron (III) content of 17.2% and each 166.6 g of the two slags of Example 46 registered.
  • Example 46 The procedure was continued as in Example 46 and the reaction was started with 429.3 g of oleum having an SO 3 concentration of 21.8%.
  • the temperature-time curve corresponded approximately to that of FIG. 3.
  • a spontaneous pressure increase occurred in the digestion vessel when the second temperature maximum was reached and the majority of the digestion mixture was discharged from the container.
  • Collected parts of the reaction mass were aged and dissolved in accordance with Example 46. There were 93.2% of the Ti0 2 used in solution. The average Ti (III) content was 6.1% of the dissolved Ti0 2 .
  • Example 49 serves as a comparative example for the subsequent experiments and, like Example 46, shows that when finely divided ilmenite is used together with relatively large-sized slags, an unfavorable course of the reaction is obtained.
  • Example 50 again shows that, according to the invention, the use of relatively coarsely divided ilmenite together with finely divided slags enables problem-free digestion behavior.
  • Example 49 The procedure was as in Example 49, with the difference that the slag A used was ground to 100% ⁇ 40 ⁇ m in a ball vibrating mill and the slag B used was also ground to 100% ⁇ 40 ⁇ m.
  • the ilmenite used was relatively coarser than the slags used.
  • Example 51 shows that it is possible to obtain digestion behavior without problems even with relatively fine-particle ilmenite, as long as it is ensured according to the invention that the slags used are relatively fine-particle than the ilmenite or, conversely, the ilmenite used is relatively larger-scale than the slags used.

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Claims (10)

1. Procédé de fabrication d'une solution de sulfate de titanyle hydrolysable à partir de mélanges de matières premières préalablement broyées renfermant de l'ilménite et du titane(III), avec attaque des mélanges de matières premières avec de l'acide sulfurique et dissolution des masses de réaction solidifiées dans un solvant aqueux, caractérisé en ce que les matières premières renfermant du titane (III) sont broyées en présence d'auxiliaires organiques appartenant au groupe des alcanolamines et/ou des polysiloxanes.
2. Procédé selon la revendication 1, caractérisé en ce que les matières premières renfermant du titane(III) sont des scories renfermant du titane(III).
3. Procédé selon l'une des revendications 1 ou 2, caractérisé en ce que l'alcanolamine est une monoisopropanolamine et/ou une diisopropanolamine et/ou une triisopropanolamine.
4. Procédé selon l'une des revendications 1 à 3, caractérisé en ce que le polysiloxane est un polysiloxane à chaîne longue et/ou ramifiée avec substituant alcoyle, acryle, cycloalcoyle et/ou hydroxyle.
5. Procédé selon la revendication 4, caractérisé en ce que le polysiloxane est un polydiméthylsi- loxane.
6. Procédé selon l'une des revendications 1 à 5, caractérisé en ce qu'on utilise les auxiliaires organiques sous la forme de solutions et/ou d'émulsions aqueuses.
7. Procédé selon l'une des revendications 1 à 6, caractérisé en ce qu'on utilise les auxiliaires organiques en des quantités de 0,002 à 0,5% en poids par rapport au mélange employé.
8. Procédé selon l'une des revendications 1 à 7, caractérisé en ce que les auxiliaires organiques sont utilisés en des quantités de 0,005 à 0,15% en poids par rapport au mélange employé.
9. Procédé selon l'une des revendications 1 à 8, caractérisé en ce que les matières premières d'ilménite employées pour l'attaque sont quant à la dimension moyenne de particule relativement plus grossières que les matières premières employées renfermant du titane(III).
10. Procédé selon 1a revendication 9, caractérisé en ce que dans l'emploi de matières premières d'ilménite ayant une dimension moyenne de particule à raison de 0 à 90% inférieure à 40 µm, on utilise des matières premières renfermant du titane(III) ayant une dimension moyenne de particule à raison de 91 à 100% inférieure à 40 µm et en ce que dans l'emploi de matières premières d'ilménite ayant une dimension moyenne de particule à raison de 0 à 60% inférieure à 40 µm on utilise des matières premières renfermant du titane(llI) ayant une dimension moyenne de particule à raison de 65 à 100% inférieure à 40 µm.
EP83106581A 1982-07-17 1983-07-06 Procédé pour la production d'une solution hydrolysable de titanylsulfate Expired EP0100865B1 (fr)

Applications Claiming Priority (4)

Application Number Priority Date Filing Date Title
DE3226893 1982-07-17
DE3226893 1982-07-17
DE3313072 1983-04-12
DE19833313072 DE3313072A1 (de) 1982-07-17 1983-04-12 Verfahren zur herstellung einer hydrolysierbaren titanylsulfatloesung

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EP0100865A1 EP0100865A1 (fr) 1984-02-22
EP0100865B1 true EP0100865B1 (fr) 1986-10-08

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EP83106581A Expired EP0100865B1 (fr) 1982-07-17 1983-07-06 Procédé pour la production d'une solution hydrolysable de titanylsulfate

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EP (1) EP0100865B1 (fr)
DE (2) DE3313072A1 (fr)
ES (1) ES8500190A1 (fr)
FI (1) FI73653C (fr)
NO (1) NO832454L (fr)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001042520A1 (fr) * 1999-12-13 2001-06-14 Pacmin Investments Limited Procede de digestion du titane contenant de la matiere et produits obtenus par ce procede

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR3031733B1 (fr) * 2015-01-16 2017-03-03 Laguelle Recipient portatif tel qu'une cuvette, une bassine ou une corbeille a linge, ainsi que procede de fabrication d'un tel recipient

Family Cites Families (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2437164A (en) * 1944-12-08 1948-03-02 Du Pont Processing of titanium ores
US2850357A (en) * 1953-05-11 1958-09-02 American Cyanamid Co Digestion of titanium dioxide slags
DE1283226B (de) * 1967-07-04 1968-11-21 Bayer Ag Verfahren zur Herstellung von Vinylacetat
DE2951799A1 (de) * 1979-12-21 1981-07-02 Bayer Ag, 5090 Leverkusen Verfahren zur herstellung einer hydrolysierbaren titanylsulfatloesung
US4321152A (en) * 1980-10-21 1982-03-23 American Cyanamid Company Grinding of titaniferous ores to enhance recovery of titanium dioxide

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2001042520A1 (fr) * 1999-12-13 2001-06-14 Pacmin Investments Limited Procede de digestion du titane contenant de la matiere et produits obtenus par ce procede

Also Published As

Publication number Publication date
NO832454L (no) 1984-01-18
DE3313072A1 (de) 1984-01-19
ES524160A0 (es) 1984-10-01
FI832578A (fi) 1984-01-18
FI832578A0 (fi) 1983-07-14
EP0100865A1 (fr) 1984-02-22
FI73653B (fi) 1987-07-31
DE3366710D1 (en) 1986-11-13
ES8500190A1 (es) 1984-10-01
FI73653C (fi) 1987-11-09

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