Cavitation process for titanium products from precursor halides
View Patent ↗A titanium halide and, optionally, other precursor halides compound are reduced to a predetermined titanium product, suitably at or near ambient conditions. Titanium tetrachloride, for example, is added to an anhydrous liquid reaction medium containing one or more alkali metals or alkaline earth metals as reductants. The metal reductants are dispersed as very small globules in the liquid by cavitation of the liquid reaction medium, such as by application of high intensity ultrasonic vibrations or high-shear mixing to the reaction vessel. Continued cavitation of the liquid medium affects relatively low temperature reduction of the precursor halide(s) to produce a titanium-containing product such as titanium metal, a titanium alloy or compound, or a titanium matrix-ceramic composite material, or the like.
1. A method of reducing a precursor halide composition comprising a titanium halide to yield a predetermined titanium-containing product, the method comprising:
circulating a dry inert gas through an anhydrous liquid reaction medium and inducing cavitation in the liquid reaction medium; and
mixing the precursor halide composition with a reductant composition in the liquid reaction medium during the cavitation to reduce the precursor halide composition to the predetermined titanium-containing product, the reductant composition consisting essentially of at least one of an alkali metal and/or an alkaline earth metal(s), the reductant composition being converted to the halide salt of the alkali metal and/or alkaline earth metal upon reaction with the precursor halide composition.
2. A method of reducing a precursor halide composition as recited in claim 1 in which the precursor halide composition consists essentially of a titanium halide and the product is titanium metal.
3. A method of reducing a precursor halide composition as recited in claim 1 in which the titanium halide is combined with the halide of at least one other metal and the product is a mixture or alloy of the other metal with titanium.
4. A method of reducing a precursor halide composition as recited in claim 1 in which the titanium halide is combined with the halide of a non-metal and the predetermined product comprises titanium and the non-metal.
5. A method of reducing a precursor halide composition as recited in claim 1 in which the liquid reaction medium is maintained at a temperature in the range of about −80° C. to about 300° C. during the cavitation and reduction of the precursor halide(s) to the predetermined product.
6. A method of reducing a precursor halide composition as recited in claim 1 in which the anhydrous liquid is a hydrocarbon liquid, a liquid comprising a silicon-containing compound, or an ionic liquid.
7. A method of reducing a precursor halide composition as recited in claim 1 in which the anhydrous liquid is a hydrocarbon liquid selected from the group consisting of decalin, tetralin, decane, dodecane, and hexadecane.
8. A method of reducing a precursor halide composition as recited in claim 1 in which the reductant composition consists essentially of a mixture of sodium and potassium that is liquid at temperatures below about 30° C.
9. A method of reducing a precursor halide composition as recited in claim 1 in which the reductant compound is initially dispersed in the liquid reaction medium and the precursor halide compound is thereafter added to the liquid reaction medium.
10. A method of reducing a precursor halide composition as recited in claim 1 in which the amount of liquid reaction medium is predetermined based on the heat of reaction of the precursor halide and the reductant material.
11. A method of reducing a precursor halide composition as recited in claim 1 in which substantially stoichiometric proportions of precursor halide(s) and reductant composition are reacted.
12. A method of reducing a precursor halide composition as recited in claim 1 in which inert gas is pumped through the liquid reaction medium in a closed circuit path.
13. A method of reducing a precursor halide composition comprising a titanium halide to yield a predetermined titanium-containing product, the method comprising:
forming a reduction reaction medium for the precursor halide composition by dispersing a reductant composition for the halide(s) in an anhydrous liquid that is non-reactive with the reductant composition using vibrations to affect cavitation in the liquid, the reductant composition consisting essentially of at least one of an alkali metal and/or alkaline earth metal;
circulating a dry inert gas through the reduction reaction medium to assist cavitation in the medium and to reduce the oxygen content of the reduction reaction medium; and, while continuing the vibrations,
adding the precursor halide composition to the reduction reaction medium to reduce the precursor halide composition to the predetermined titanium-containing product and to concurrently form a corresponding halide salt of the alkali metal and/or alkaline earth metal(s).
14. A method of reducing a precursor halide composition as recited in claim 13 in which the precursor halide composition consists essentially of a titanium halide and the product is titanium metal.
15. A method of reducing a precursor halide composition as recited in claim 13 in which the titanium halide is combined with the halide of at least one other metal and the product is a mixture or alloy of the other metal with titanium metal.
16. A method of reducing a precursor halide composition as recited in claim 13 in which the titanium halide is combined with the halide of a non-metal and the predetermined product comprises titanium and the non-metal.
17. A method of reducing a precursor halide composition as recited in claim 13 in which the anhydrous liquid is a hydrocarbon liquid, a liquid containing silicon, or an ionic liquid.
18. A method of reducing a precursor halide composition as recited in claim 13 in which the precursor halide composition comprises titanium tetrachloride.
19. A method of reducing a precursor halide composition as recited in claim 13 in which the precursor halide composition comprises titanium tetrachloride and vanadium chloride and the predetermined titanium-containing product comprise a mixture of titanium and vanadium.
20. A method of reducing a precursor halide composition as recited in claim 13 in which a titanium chloride is combined with a silicon chloride and the product comprises titanium disilicide.
21. A method of reducing a precursor halide composition as recited in claim 13 further comprising dissolving the alkali or alkaline earth metal halide in a solvent to separate it from the predetermined product.
22. A method of reducing a precursor halide composition to yield a predetermined product as recited in claim 21 , the method further comprising removing solvent from the predetermined product by heating the product in a vacuum oven.
23. A method of reducing a precursor halide composition to yield a predetermined product as recited in claim 13 , the method further comprising annealing or melting the titanium-containing product by heating the product in a vacuum oven at a temperature in the range of about 573 K to about 2100 K.
24. A method of reducing a precursor halide composition comprising titanium tetrachloride to yield a predetermined titanium-containing product, the method comprising:
forming a reduction reaction medium for the precursor halide composition by dispersing a reductant composition for the halide(s) in an anhydrous liquid that is non-reactive with the reductant composition using vibrations to affect cavitation in the liquid, the reductant composition consisting essentially of a mixture of sodium and potassium that is liquid at temperatures below about 30° C.;
circulating a dry inert gas through the reduction reaction medium to assist cavitation in the medium and to reduce the oxygen content and water content of the reduction reaction medium; and, while continuing the vibrations,
adding the precursor halide composition to the reduction reaction medium to reduce the precursor halide composition to the predetermined titanium-containing product and to concurrently form corresponding halide salts of the sodium and potassium; and
separating the predetermined product from the halide salts of sodium and potassium.