Feedstock composites containing density-controlled carbonaceous materials - Patent Application 20070122997

Abstract

The present invention relates to a feedstock composite comprising a metal oxide fraction and a carbonaceous fraction, a binder composition and its use for obtaining the feedstock composite. Furthermore, the present invention relates to a method for obtaining the feedstock composite.

Description

[Technical Field]

[0001] The present invention relates to a feedstock composite comprising a metal oxide fraction and a carbonaceous fraction, a binder composition and its use for obtaining the feedstock composite. Furthermore, the present invention relates to a method for obtaining the feedstock composite.

[0002] Background technology Carbochlorination processes are processes in which metal oxides are converted to their corresponding metal chlorides in the presence of chlorine gas and carbonaceous materials. The most common carbochlorination processes involve the processing of feedstocks, such as ores and slags containing oxides of refractory metals, especially niobium, tantalum, tungsten, molybdenum, and rhenium, or rare earth metals, such as cerium, neodymium, and samarium, or oxides of light metals, such as aluminum, silicon, vanadium, or titanium, or of other metals, such as zirconium. Metal chlorides often exhibit relatively low vapor pressures and can be removed from their original solid matrix by sublimation or purified by fractional sublimation or distillation, taking advantage of their different boiling points, with or without the use of solvents. Furthermore, metal chlorides can also be purified by extraction or other separation methods.

[0003] Typically, metal chlorides are further processed to metals, metal alloys, or purified oxides or hydroxides, all of which are economically attractive. One of the most important carbochlorination processes is the chloride method for the production of titanium dioxide.

[0004] Titanium dioxide is produced by either the well-established sulfate or chloride process. The latter uses a titanium-containing feedstock that is subjected to a carbochlorination process. The chloride thus obtained is then separated by resublimation or distillation. Titanium tetrachloride is finally converted to titanium dioxide, and the chlorine liberated from the aforementioned reaction is separated and reused in the reaction with the titanium-containing feedstock. Among other reasons, the reuse of chlorine makes the chloride process more economically attractive than the sulfate process.

[0005] The coke selected for this process is petroleum coke with a specific particle size. Due to its small particle size and low weight, fine petroleum coke is discharged from the reactor and is therefore unsuitable for the carbochlorination reaction itself. The same applies to green coke and sustainable coke derived from renewable sources, such as charcoal or biochar, because they have low particle density and low inlet bulk density. Furthermore, the demand for petroleum coke continues to increase due to the attractiveness of the chloride process compared to the sulfate process. This increased demand leads to an increase in the price of petroleum coke. Although alternative cokes are available at lower costs, the above facts make them unsuitable for the carbochlorination process.

[0006] Therefore, there is a need in the art for a feedstock for carbochlorination processes using cokes other than petroleum coke, particularly for titanium dioxide chloride processes, that has specific physical properties that qualify the material.

[0007] Summary of the Invention Problems that the invention aims to solve It is an object of the present invention to use carbonaceous materials that are unsuitable due to their inlet bulk and particle densities as feedstock in carbochlorination processes.

[0008] This object is achieved by a feedstock composite, a binder composition, its uses, and a method for obtaining said feedstock composite.

[0009] The present invention comprises a metal oxide fraction and a carbonaceous fraction, wherein the carbonaceous fraction has a concentration of 0.8 g / cm 3 or less, preferably 0.7 g / cm 3 or less, more preferably 0.6 g / cm 3 Inlet bulk density of less than or equal to 0.85 g / cm 3 ~1.15g / cm 3 The present invention provides a feedstock composite characterized by having a particle density of at least 0.8 g / cm. This carbonaceous material can be selected from a wide variety of cokes that are not suitable for carbochlorination reactions, for example, biochar, or may be derived from pyrolytic coke and peat. As a result, certain physical properties, in particular a particle density of at least 0.8 g / cm, are achieved. 3 Expensive petroleum coke, having an inlet bulk density of 0.15, is not the only eligible raw material as a carbonaceous feedstock for the carbochlorination reaction.

[0010] Thus, in a first aspect, the present invention provides a carbonaceous material comprising a metal oxide fraction and a carbonaceous fraction, the carbonaceous fraction having a density of 0.8 g / cm 3 or less, preferably 0.7 g / cm 3 or less, more preferably 0.6 g / cm 3 Inlet bulk density of less than or equal to 0.85 g / cm 3 ~1.15g / cm 3 The present invention relates to a feedstock composite characterized by having a particle density of

[0011] In a second aspect, the present invention relates to a binder composition comprising a lignosulfonate, carboxymethyl cellulose and water glass.

[0012] In a further aspect, the present invention relates to the use of the binder composition disclosed herein to obtain a feedstock composite comprising a metal oxide fraction and a carbonaceous fraction.

[0013] In yet a further aspect, the present invention provides a method for obtaining the feedstock composite disclosed herein, comprising: a) a feed mixture of a titanium-containing material and a carbonaceous material, wherein the carbonaceous material is present in an amount of 0.8 g / cm 3 or less, preferably 0.7 g / cm 3 or less, more preferably 0.6 g / cm 3 a) providing a feed mixture having an inlet bulk density of:

[0014] Further advantageous embodiments of the invention are set forth in the dependent claims.

[0015] MODE FOR CARRYING OUT THE INVENTION These and other aspects, features, and advantages of the present invention will become apparent to those skilled in the art upon review of the following detailed description and claims. Each feature from one aspect of the present invention can be used in any other aspect of the present invention. Numerical ranges stated in the format "from x to y" include the stated value and values ​​within the respective measurement precision known to those skilled in the art. When several preferred numerical ranges are stated in this format, it goes without saying that all ranges formed by combining the various endpoints are also included.

[0016] In a first aspect, the present invention relates to a feedstock composite comprising a metal oxide fraction and a carbonaceous fraction, wherein the carbonaceous fraction has a density of 0.8 g / cm 3 or less, preferably 0.7 g / cm 3 or less, more preferably 0.6 g / cm 3 Inlet bulk density of less than or equal to 0.85 g / cm 3 ~1.15g / cm 3 The inlet bulk density of the carbonaceous fraction is preferably 0.3 g / cm 3 or less, more preferably 0.2 g / cm 3 The feedstock is preferably 0.7 g / cm 3 ~2.0g / cm 3, more preferably 0.9 g / cm 3 ~1.7g / cm 3 , and even more preferably 1.2 g / cm 3 ~1.5g / cm 3 In a preferred embodiment, the feedstock composite has an inlet bulk density of preferably 0.7 g / cm 3 ~2.0g / cm 3 , preferably 0.9 g / cm 3 ~1.7g / cm 3 , more preferably 1.2 g / cm 3 ~1.5g / cm 3 In yet another preferred embodiment, the feedstock composite has a particulate form, preferably the particles have a size of 0.1 mm to 6.0 mm, preferably 0.3 mm to 4.0 mm, more preferably 0.5 mm to 3.0 mm, which makes the composite highly suitable for the carbochlorination process.

[0017] As used herein, "inlet bulk density" refers to the mass per volume of the feedstock and the continuous fluid filling the voids between the composite feedstock, where the fluid is air and the individual components of the feedstock must not dissolve in one another. The inlet bulk density was determined using the procedure described in DIN 53468. As used herein, "particle density" refers to the mass per volume of solids. The inlet bulk density was determined using the procedure described in ISO 12154.

[0018] The carbonaceous fraction may preferably be selected from the group consisting of fine petroleum coke, recycled petroleum coke, biochar, charcoal, pyrolytic lignite, pyrolytic peat and pyrolytic coke. Additionally, materials such as coke produced from organic recycled materials or secondary or tertiary feedstocks by, for example, pyrolysis and similar processes to produce coke, sewage sludge, compost, wood, straw or other agricultural residues, hydrothermally produced coke (HTC) from appropriate fractions of municipal waste, etc. As used herein, "fine petroleum coke" refers to a carbonaceous fraction having a carbon content of 0.5 g / cm. 3 or less, preferably 0.4 g / cm3 Refers to petroleum coke having the following inlet bulk density:

[0019] The metal oxide fraction can be any metal oxide used as a starting material in the carbochlorination process, including any metal of interest, such as refractory metals, especially niobium, tantalum, tungsten, molybdenum, and rhenium; rare earth metals, such as cerium, neodymium, and samarium; light metals, such as aluminum, silicon, vanadium, or titanium; or other metals, such as zirconium. Preferably, ores and slags containing the above can be used. Preferably, the metal oxide fraction is a titanium-containing fraction, which is selected from the group consisting of natural rutile, synthetic rutile, titanium-containing slag, recycled titanium-containing slag, residual slag, and ilmenite. The residual slag can originate from the iron and steel industry.

[0020] To improve the adhesion of the composite feedstock fractions, at least one binder selected from the group consisting of sodium chloride, sodium carbonate, bentonite, water glass, carbon black, soy, polyvinyl alcohol, plasticizers, lignosulfonates, carboxymethylcellulose, starch, starch ethers, tar, bitumen, molasses, natural resins, pitch, gelatin, and tannins can be used. Starch ethers can be obtained from Agrana Beteilungs-AG (Vienna, Austria). It is advantageous to use a binder composition in the carbochlorination process that contains lignosulfonates, carboxymethylcellulose, water glass, and bentonite, preferably in a ratio of 1:2:2:2 to 1:3:4:4. Preferably, the feedstock composite further comprises at least one binder or binder composition in an amount of from 1% to 20% by weight, preferably from 3% to 17.5% by weight, more preferably from 7.5% to 13% by weight, based on the total weight of the feedstock composite.

[0021] In another aspect, the present invention relates to a binder composition comprising lignosulfonate, carboxymethyl cellulose, water glass, and bentonite, preferably in a ratio of lignosulfonate, carboxymethyl cellulose, water glass, and bentonite of 1:2:2:2 to 1:3:4:4.

[0022] In a further aspect, the present invention relates to a binder composition as disclosed herein for obtaining a feedstock composite comprising a metal oxide fraction and a carbonaceous fraction, preferably for obtaining a feedstock composite as described herein. Even more preferably, the binder composition according to the present invention is used for obtaining a feedstock composition for a titanium dioxide chloride process.

[0023] In a further aspect, the present invention provides a method for obtaining a feedstock composite comprising a metal oxide fraction and a carbonaceous fraction, the method comprising: a) A raw material mixture of a metal oxide material and a carbonaceous material, wherein the carbonaceous material is present in an amount of 0.8 g / cm 3 or less, preferably 0.7 g / cm 3 or less, more preferably 0.6 g / cm 3 providing a feedstock mixture having an inlet bulk density of: b) agglomerating the raw material mixture to obtain a feedstock composite The present invention relates to a method comprising:

[0024] The agglomeration in step (a) can be achieved by compression and / or extrusion and / or wet extrusion, preferably by extrusion. Additionally, pressure agglomeration, dry agglomeration, tumble expansion agglomeration, heating or sintering can also be used.

[0025] Preferably, after step a) and before step b), the raw material mixture is mixed by drying, wetting and / or pre-agglomeration. This step is carried out to prepare the raw material mixture for step b). The equipment and techniques are known in the art, for example, a disk pelletizer. The particle size of the feedstock can also be adjusted by common reduction techniques.

[0026] The metal oxide fraction can be any metal oxide used as a starting material in the carbochlorination process, including any metal of interest, such as refractory metals, especially niobium, tantalum, tungsten, molybdenum, and rhenium; rare earth metals, such as cerium, neodymium, and samarium; light metals, such as aluminum, silicon, vanadium, or titanium; or other metals, such as zirconium. Preferably, ores and slags containing the above can be used. Preferably, the metal oxide fraction is a titanium-containing fraction, which is selected from the group consisting of natural rutile, synthetic rutile, titanium-containing slag, recycled titanium-containing slag, residual slag, and ilmenite. The residual slag can originate from the iron and steel industry.

[0027] To improve the adhesion of the composite feedstock fractions, at least one binder selected from the group consisting of sodium chloride, sodium carbonate, bentonite, water glass, carbon black, soy, polyvinyl alcohol, plasticizers, lignosulfonates, carboxymethylcellulose, starch, starch ethers, tar, bitumen, molasses, natural resins, pitch, gelatin, and tannins can be added during step a). Starch ethers can be obtained from Agrana Beteilungs-AG (Vienna, Austria). It is advantageous to use a binder composition in the carbochlorination process that contains lignosulfonates, carboxymethylcellulose, water glass, and bentonite, preferably in a ratio of lignosulfonates, carboxymethylcellulose, water glass, and bentonite of 1:2:2:2 to 1:3:4:4. Preferably, the feedstock composite further comprises at least one binder or binder composition in an amount of from 1% to 20% by weight, preferably from 3% to 17.5% by weight, more preferably from 7.5% to 13% by weight, based on the total weight of the feedstock composite.

Claims

1. It contains a metal oxide fraction and a carbonaceous fraction, The carbonaceous fraction is 0.8 g / cm³. ３ The following are preferred 0.7 g / cm ３ More preferably, 0.6 g / cm³ ３ The following inflow bulk densities, and 0.85 g / cm ３ ~1.15 g / cm ３ Having a particle density Feedstock composite material characterized by the following features.

2. The feedstock composite preferably has a bulk density of 0.7 g / cm ３ to 2.0 g / cm ３ Preferably 0.9 g / cm ３ to 1.7 g / cm ３ More preferably 1.2 g / cm ３ to 1.5 g / cm ３ The feedstock composite according to claim 1, characterized in that it has a bulk density of inflow within the above range.

3. The feedstock composite material according to claim 1, characterized in that the carbonaceous fraction is selected from the group consisting of fine petroleum coke, recycled petroleum coke, biochar, charcoal, pyrolytic lignite, pyrolytic peat, and pyrolytic coke.

4. The feedstock composite material according to claim 1, characterized in that the feedstock composite material has the form of particles, preferably the particles having a size of 0.1 mm to 6.0 mm, preferably 0.3 mm to 4.0 mm, and more preferably 0.5 mm to 3.0 mm.

5. The feedstock composite material according to claim 1, characterized in that the metal oxide fraction is a titanium-containing fraction, and the titanium-containing fraction is selected from the group consisting of natural rutile, synthetic rutile, titanium slag, recycled titanium slag, residue slag, and ilmenite.

6. The feedstock composite according to claim 1, characterized in that the feedstock composite further comprises at least one binder selected from the group consisting of sodium chloride, sodium carbonate, bentonite, water glass, carbon black, soth, polyvinyl alcohol, plasticizer, lignosulfonate, carboxymethylcellulose, starch, starch ether, tar, bitumen, molasses, natural resin, pitch, gelatin, and tannin.

7. The feedstock composite according to claim 6, wherein the feedstock composite further comprises a binder composition comprising lignosulfonate, carboxymethylcellulose, water glass, and bentonite, and preferably the ratio of lignosulfonate, carboxymethylcellulose, water glass, and bentonite is 1:2:2:2 to 1:3:4:

4.

8. The feedstock composite material according to claim 6, characterized in that the feedstock composite material further comprises at least one binder or binder composition in an amount of 1% to 20% by weight, preferably 3% to 17.5% by weight, and more preferably 7.5% to 13% by weight, based on the total weight of the feedstock composite material.

9. A binder composition comprising lignosulfonate, carboxymethylcellulose, water glass, and bentonite.

10. The ratio of lignosulfonate, carboxymethylcellulose, water glass, and bentonite is The ratio must be between 1:2:2:2 and 1:3:4:

4. The binder composition according to claim 9, characterized by the above.

11. Use of the binder composition according to claim 9 to obtain a feedstock composite containing a metal oxide fraction and a carbonaceous fraction.

12. Use of the binder composition according to claim 11 to obtain the feedstock composite material according to any one of claims 1 to 8.

13. Use of the binder composition according to claim 9 to obtain a feedstock composition for the titanium dioxide chlorination method.

14. A method for obtaining a feedstock composite material containing a metal oxide fraction and a carbonaceous fraction, a) A raw material mixture of a metal oxide material and a carbonaceous material, wherein the carbonaceous material is present in a concentration of 0.8 g / cm³. ３ Preferably, 0.7 g / cm³ ３ More preferably, 0.6 g / cm³ ３ A step of providing a raw material mixture having the following inflow bulk density, and b) A step of agglomerating the raw material mixture to obtain the feedstock composite material. A method that includes this.

15. The metal oxide fraction is a titanium-containing fraction, and the titanium-containing fraction is selected from the group consisting of natural rutile, synthetic rutile, titanium slag, recycled titanium slag, residue slag, and ilmenite. The method according to claim 14, characterized by the above.

16. In step a), at least one binder selected from the group consisting of sodium chloride, sodium carbonate, bentonite, water glass, carbon black, soth, polyvinyl alcohol, plasticizer, lignosulfonate, carboxymethylcellulose, starch, starch ether, tar, bitumen, molasses, natural resin, pitch, gelatin, and tannin is added to the raw material mixture. The method according to claim 14, characterized by the above.

17. During step a), or after step a) and before step b), add a binder composition containing lignosulfonate, carboxymethylcellulose, water glass, and bentonite, preferably in a ratio of 1:2:2:2 to 1:3:4:

4. The method according to claim 14, characterized by the above.

18. The method according to claim 14, characterized in that the agglomeration in step b) is achieved by compression and / or extrusion and / or wet extrusion and / or pressure agglomeration and / or dry agglomeration and / or tumble expansion agglomeration and / or heating and / or sintering, preferably by extrusion.

19. After step a) and before step b), A process of mixing raw material mixtures by drying, wetting, and / or pre-aggregation. The method according to claim 14, including the method described in claim 14.