阅读说明：本技术 一种高纯无水氟化锆的制备方法 (Preparation method of high-purity anhydrous zirconium fluoride ) 是由 严永生 于 2020-12-22 设计创作，主要内容包括：本发明公开了一种高纯无水氟化锆的制备方法,其中将氧化锆与过量电子级氢氟酸(大于30%)在30~60℃下反应制备得到氟锆酸溶液。氟锆酸溶液经浓缩蒸干后得到水合氟化锆(ZrF_4·4H2O),水合氟化锆经320℃真空烘焙(压力小于10Pa)12h以上得到总氧含量约2000ppm的粗氟化锆,在于450℃保温4h以上升温至800~1000℃惰性气氛下升华4h以上可得到总氧含量小于100ppm的高纯无水氟化锆晶体。(The invention discloses a preparation method of high-purity anhydrous zirconium fluoride, wherein zirconium oxide and excess electronic-grade hydrofluoric acid (more than 30%) react at the temperature of 30-60 ℃ to prepare a fluozirconate solution. The zirconic acid solution is concentrated and evaporated to dryness to obtain zirconium fluoride hydrate (ZrF) 4 4H 2O), baking the hydrated zirconium fluoride in vacuum at 320 ℃ for more than 12H (the pressure is less than 10 Pa) to obtain crude zirconium fluoride with the total oxygen content of about 2000ppm, and sublimating at 450 ℃ for more than 4H under the inert atmosphere at 800-1000 ℃ to obtain high-purity anhydrous zirconium fluoride crystals with the total oxygen content of less than 100 ppm.)

1. The preparation method of the high-purity anhydrous zirconium fluoride is characterized by comprising the following steps of:

the preparation method comprises the steps of preparing zirconium fluoride, wherein high-purity grade or reagent grade zirconium oxide and excessive electronic grade hydrofluoric acid are reacted for 1-4 hours at the temperature of 30-60 ℃ to obtain zirconium fluosilicate;

concentrating and evaporating a fluorozirconic acid solution to obtain hydrated zirconium fluoride, and drying the hydrated zirconium fluoride at 300-350 ℃ in vacuum (absolute pressure is 1-10 pa) for 10-15 hours to obtain crude zirconium fluoride with total oxygen content of 2000ppm (mg/kg);

and thirdly, preserving the heat of the zirconium fluoride at 450 ℃ for 4 hours, heating the zirconium fluoride to 800-1000 ℃ and subliming the zirconium fluoride for more than 4 hours under the inert atmosphere to obtain the high-purity anhydrous zirconium fluoride crystal with the total oxygen content of less than 100 ppm.

2. The method for preparing high-purity anhydrous zirconium fluoride according to claim 1, characterized in that: electronic grade hydrofluoric acid is used, which has a metal ion content of less than 10ppb (micrograms/kg).

3. The method for preparing high-purity anhydrous zirconium fluoride according to claim 1, characterized in that: zirconia is chemically pure or analytically pure or higher grade zirconia reagents.

4. The method for preparing high-purity anhydrous zirconium fluoride according to claim 1, characterized in that: reacting zirconium oxide with excessive hydrofluoric acid (more than 30%) at 30-60 ℃ to prepare fluorozirconic acid solution, concentrating and evaporating the fluorozirconic acid solution to dryness to obtain zirconium fluoride hydrate (ZrF)₄4H 2O), baking the hydrated zirconium fluoride in vacuum at 320 ℃ for more than 12H (the pressure is less than 10 Pa) to obtain crude zirconium fluoride with the total oxygen content of about 2000ppm, and sublimating at 450 ℃ for more than 4H under the inert atmosphere at 800-1000 ℃ to obtain high-purity anhydrous zirconium fluoride crystals with the total oxygen content of less than 100 ppm.

Technical Field

The invention relates to a preparation method of high-purity anhydrous zirconium fluoride, belonging to the field of fine chemicals in chemical engineering.

Background

the high-purity zirconium fluoride can be used in fused salt energy storage technology, which uses fused salt as heat transfer medium, and is combined with solar energy photo-thermal power generation system, to make the photo-thermal power generation system have energy storage and night power generation capability, and meet the peak regulation requirement of power network. According to different heat energy storage modes, solar high-temperature energy storage technologies can be divided into sensible heat energy storage, latent heat energy storage and hybrid energy storage.

Sensible heat energy storage is mainly used for storing heat energy through the temperature rise or fall of a certain material, and is a heat storage mode which is mature in technology, rich in material source and low in cost at present. Sensible heat energy storage includes two jar energy storage (conduction oil, fused salt), vapor energy storage, solid energy storage (concrete, pottery), single-tank thermocline energy storage (conduction oil, fused salt) etc. latent heat energy storage absorbs or releases the heat and realizes the storage of energy when mainly taking place the phase transition through heat storage material, has that heat accumulation density is big, fills, advantage such as the heat release process fluctuation temperature scope is little, latent heat energy storage includes fused salt phase change energy storage, fused salt + inorganic material composite phase change energy storage etc..

A Molten Salt nuclear Reactor (MSR) is a Reactor using Molten Salt in a Molten state, in which a fissile material is dissolved, as nuclear fuel, and is a Reactor of a nuclear power generation technology commonly used at present. The molten salt nuclear reactor is a liquid nuclear fuel prepared by directly dissolving nuclear fuel into molten salt in a molten state. The molten salt nuclear reactor has many advantages of extremely high neutron economy, high power density, controllable inherent load, large negative temperature coefficient, high conversion ratio, high reliability, low fuel combination consumption, high proliferation and the like, and is determined to be one of the preferentially developed fourth generation nuclear reactor design schemes on the fourth generation nuclear reactor international seminar held by tokyo in 2002, and the molten salt has high requirements on the contents of anions and metal ions, wherein the contents of the metal ions are less than 100ppm, and in addition, the metal ions are Fe ions, Co ions, Ni ions, Mn ions, Cr ions, Ti ions, Mo ions, Al ions and W ions are controlled in the molten salt content, the contents cannot be too high, and the oxygen content is less than 100ppm, so that the generation of hydrogen is prevented.

Disclosure of Invention

The invention aims to solve the technical problem that in the current preparation method of high-purity zirconium fluoride, zirconium fluoride is dried under the protection of inert gas.

In order to solve the technical problems, the invention adopts the following technical scheme:

a preparation method of high-purity anhydrous zirconium fluoride comprises the following steps:

firstly, preparing zirconium fluoride, namely reacting high-purity grade or reagent grade zirconium oxide with excessive electronic grade hydrofluoric acid at the temperature of 30-60 ℃ for 1-4 hours to obtain fluozirconic acid;

concentrating and evaporating a fluorozirconic acid solution to obtain hydrous zirconium fluoride, and drying the hydrous zirconium fluoride at the temperature of 300-350 ℃ in vacuum (absolute pressure of 1-10 pa) for 10-15 hours to obtain crude zirconium fluoride with total oxygen content of 2000ppm (mg/kg);

and thirdly, maintaining the temperature of the zirconium fluoride at 450 ℃ for 4 hours, heating the zirconium fluoride to 800-1000 ℃ and subliming the zirconium fluoride for more than 4 hours under the inert atmosphere to obtain the high-purity anhydrous zirconium fluoride crystal with the total oxygen content of less than 100 ppm.

The electronic-grade hydrofluoric acid adopts electronic-grade hydrofluoric acid with the metal ion content of less than 10ppb (microgram/kilogram).

The zirconia is prepared by adopting a chemically pure or analytically pure or higher-grade zirconia reagent.

And reacting the zirconium oxide with excessive hydrofluoric acid (more than 30%) at 30-60 ℃ to prepare the fluozirconic acid solution. The zirconic acid solution is concentrated and evaporated to dryness to obtain zirconium fluoride hydrate (ZrF)₄4H 2O), baking the hydrated zirconium fluoride in vacuum at 320 ℃ for more than 12H (the pressure is less than 10 Pa) to obtain crude zirconium fluoride with the total oxygen content of about 2000ppm, keeping the temperature at 450 ℃ for more than 4H, heating to 800-1000 ℃ under an inert atmosphere, and sublimating for more than 4H to obtain high-purity anhydrous zirconium fluoride crystals with the total oxygen content of less than 100 ppm.

The involved reaction equation:

preparation of fluorozirconic acid

Fluozirconic acid evaporating to dryness

Baking at 320 DEG C

Keeping the temperature at 450 ℃.

Detailed Description

Example 1:

7.3g of zirconia was reacted with an excess of 52g of hydrofluoric acid (30%) at 30 ℃ to prepare a fluorozirconic acid solution. The zirconic acid solution is concentrated and evaporated to dryness to obtain zirconium fluoride hydrate (ZrF)₄4H 2O), vacuum baking of hydrous zirconium fluoride at 300 ℃ for more than 10H (pressure less than 10 Pa) to obtain crude zirconium fluoride having a total oxygen content of about 2000ppm, raising the temperature to 800 ℃ at 450 ℃ for more than 4HSublimating for more than 4 hours under inert atmosphere to obtain high-purity anhydrous zirconium fluoride crystals with the total oxygen content of less than 100 ppm.

Example 2:

7.3g of zirconia was reacted with an excess of 52g of hydrofluoric acid (49%) at 60 ℃ to prepare a fluorozirconic acid solution. The zirconic acid solution is concentrated and evaporated to dryness to obtain zirconium fluoride hydrate (ZrF)₄4H 2O), vacuum baking the hydrated zirconium fluoride at 350 ℃ for more than 15H (with the pressure less than 5 Pa) to obtain crude zirconium fluoride with the total oxygen content of about 2000ppm, and sublimating at 450 ℃ for more than 4H under the inert atmosphere at the temperature of 1000 ℃ to obtain high-purity anhydrous zirconium fluoride crystals with the total oxygen content of less than 100 ppm.

Example 3:

7.3g of zirconia was reacted with an excess of 52g of hydrofluoric acid (40%) at 45 ℃ to prepare a fluorozirconic acid solution. The zirconic acid solution is concentrated and evaporated to dryness to obtain zirconium fluoride hydrate (ZrF)₄4H 2O), vacuum baking the hydrated zirconium fluoride at 320 ℃ for more than 12H (with the pressure less than 2 Pa) to obtain crude zirconium fluoride with the total oxygen content of about 2000ppm, and sublimating at 450 ℃ for more than 4H under the inert atmosphere of which the temperature is raised to 900 ℃ to obtain high-purity anhydrous zirconium fluoride crystals with the total oxygen content of less than 100 ppm.