Method for separating the mixture of zirconium oxide/hafnium oxide by pyrometallurgy

Abstract

A method for separating zirconium oxide/hafnium oxide by pyrometallurgy. The mixture of zirconium oxide/hafnium oxide, carbon and pure bromine react one hour at 650? C., then added to molten salt mixture for rectifying separation, and then maintained two hours at rectifying tower bottom below 357? C., to get the non-target substance; and then maintained five hours at 357? C. to collect the target substance zirconium tetrabromide; the residue in the reactor is retained, then rectification separation is performed in the same device, heated to 400? C. to retain more than five hours, to get hafnium tetrabromide, then the zirconium tetrabromide and hafnium tetrabromide are substituted by magnesium to get the pure zirconium and pure hafnium.

Claims

1. A method for separating zirconium oxide and hafnium oxide from a mixture of zirconium oxide and hafnium oxide comprises the following steps: mixing the mixture of zirconium oxide and hafnium oxide, carbon and pure bromine, reacting one hour at 650? C. which results in a mixture of zirconium tetrabromide and hafnium tetrabromide; adding the mixture of zirconium tetrabromide and hafnium tetrabromide into molten salt for rectification separation, and maintaining the rectification for two hours at 200-357? C. which yields a non-target substance at the top of a rectification tower, wherein the molten salt is a molten mixture of potassium fluoride and aluminum potassium sulfate with a weight ratio of 1.2-1.6:1; maintaining for additional five hours at 357? C.-360? C., collecting a target substance zirconium tetrabromide from the top of the rectification tower; performing the rectification separation in the rectification tower, heat up to 400-403? C. and maintaining for five hours, and then collecting the hafnium tetrabromide from the top of the rectification tower.

2. The method according to claim 1, wherein the temperature for collecting the zirconium tetrabromide is 357? C.

3. The method according to claim 1, wherein the temperature for collecting the hafnium tetrabromide is 400? C.

4. The method according to claim 1, wherein it further comprises: performing a magnetism replacement for the zirconium tetrabromide which yields a pure zirconium.

5. The method according to claim 1, wherein it further comprises: performing a magnetism replacement for the hafnium tetrabromide which yields a pure hafnium.

Description

DETAILED DESCRIPTIONS OF THE PREFERRED EMBODIMENTS

(1) The invention is further described in details in combination with several preferred embodiments. The embodiments herein are only used to clarify this invention rather than a limitation on the mode of execution of the invention.

(2) Embodiment 1

(3) The zirconium, hafnium oxides are added in a high-temperature corrosion-resistant ceramic reactor, then the corresponding carbon is added. The vaporized pure bromine is added to the high-temperature reactor through the nitrogen, to maintain the reactor at 650? C.; when the raw material bromine is added, maintained one hour at 650? C., then cooled down to get the mixture of zirconium tetrabromide and hafnium tetrabromide.

(4) The next step is separation in the rectifying tower. The mixture of zirconium tetrabromide and hafnium tetrabromide is added in a high-temperature corrosion-resistant ceramic reactor, then the molten salt mixture is added, and the molten salt is the mixture of the potassium fluorine and aluminum potassium sulfate at a weight ratio of 1.2?1.6:1, then maintained two hours below 357? C., to get the non-target substance, then maintained five hours at 357? C., to collect the target substance of high purity of zirconium tetrabromide compound. The residues are retained in the reactor, since it has small amount; when N batches are collected and sufficient raw materials are available, perform rectification separation in the same device, heat to 400? C. to maintain more than five hours, to get the highly pure hafnium tetrabromide compound.

(5) All distillation equipments in the invention are domestic equipments; infrared heating, ceramic materials are used, and the filler in the rectifying tower is corrugated ceramic filler. The synthesis of nuclear grade materials: the highly pure zirconium tetrabromide and hafnium tetrabromide compounds obtained through rectification and separation and the magnesium powder have a reduction reaction, to get the high-purity zirconium sponge and high-purity hafnium sponge. It can be used for deep processing and production of nuclear zirconium and nuclear hafnium materials.