Cavitation process for products from precursor halides
View Patent ↗A precursor halide compound is reduced to a predetermined product at substantially ambient conditions. The halide 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, such as by application of high intensity ultrasonic vibrations or high-shear mixing to the reaction vessel. Continued cavitation of the liquid medium affects low temperature reduction of the precursor halide(s) to produce a metal, metal alloy, metal compound, ceramic material, metal matrix-ceramic composite material, or the like. The practice may be applied, for example, to titanium tetrachloride, alone or with other chlorides, to produce titanium metal, titanium alloys (for example Ti-6Al-4V), and titanium compounds (TiSi 2 ).
1. A method of reducing a least one precursor halide compound to yield a predetermined product, the method comprising:
circulating a dry inert gas through an anhydrous liquid reaction medium and inducing cavitation in the liquid reduction medium; and
mixing at least one precursor halide compound with a reductant composition in the liquid reaction medium during the cavitation to reduce the precursor halide compound(s) to the predetermined 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 compound.
2. A method of reducing at least one precursor halide compound 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.
3. A method of reducing at least one precursor halide compound as recited in claim 1 in which the liquid reaction medium is initially at ambient temperature.
4. A method of reducing at least one precursor halide compound 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.
5. A method of reducing at least one precursor halide compound 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.
6. A method of reducing at least one precursor halide compound as recited in claim 1 in which the reductant composition consists essentially of a mixture of sodium and potassium.
7. A method of reducing at least one precursor halide compound 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.
8. A method of reducing at least one precursor halide compound 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.
9. A method of reducing at least one precursor halide compound 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.
10. A method of reducing at least one precursor halide compound as recited in claim 1 in which substantially stoichiometric proportions of precursor halide(s) and reductant composition are reacted.
11. A method of reducing at least one precursor halide compound as recited in claim 1 in which inert gas is pumped through the liquid reaction medium in a closed circuit path.
12. A method of reducing at least one precursor halide compound to yield a predetermined product, the method comprising:
forming a reduction reaction medium for the precursor halide by dispersing a reductant composition for the precursor halide 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 return volatile material to the reduction reaction medium; and, while continuing the vibrations,
adding the at least one precursor halide to the reaction medium to reduce the precursor halide to the predetermined product and to concurrently form a corresponding halide salt of the alkali metal and/or alkaline earth metal(s).
13. A method of reducing at least one precursor halide compound as recited in claim 12 in which the precursor halide compound(s) are chloride(s).
14. A method of reducing at least one precursor halide compound as recited in claim 12 in which the anhydrous liquid is a hydrocarbon liquid, a liquid comprising a silicon-containing compound, or an ionic liquid.
15. A method of reducing at least one precursor halide compound as recited in claim 12 in which the anhydrous liquid is a hydrocarbon liquid selected from the group consisting of decalin, tetralin, decane, dodecane, and hexadecane.
16. A method of reducing at least one precursor halide compound as recited in claim 12 in which the reductant composition consists essentially of a mixture of sodium and potassium.
17. A method of reducing at least one precursor halide compound as recited in claim 12 in which the reductant composition consists essentially of a mixture of sodium and potassium that is liquid at temperatures below about 30° C.
18. A method of reducing at least one precursor halide compound as recited in claim 12 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.
19. A method of reducing at least one precursor halide compound as recited in claim 12 in which substantially stoichiometric proportions of precursor halide(s) and reductant composition are reacted.
20. A method of reducing at least one precursor halide compound as recited in claim 12 in which the precursor halide(s) is a chloride compound(s) and the predetermined product is one of titanium powder, titanium disilicide powder, platinum zirconium powder, or zirconium powder.