Method of producing uranium tetrafluoride

FIELD: chemistry.

SUBSTANCE: invention relates to chemical engineering of inorganic substances and can be used to produce uranium tetrafluoride. The method of producing uranium tetrafluoride involves reduction and fluorination of triuranium octoxide with vapour from decomposition of ammonium fluoride taken in excess of 100-130 mol. % of the stoichiometric amount at temperature in the range of 260-700°C.

EFFECT: invention provides a simple industrial method of producing uranium tetrafluoride and reduces the cost of the product.

3 ex

 

The invention relates to the field of chemical technology of inorganic substances and can be used in cases when you need to be tetraploid uranium.

A known method of producing uranium tetrafluoride by the interaction of uranium dioxide UO2with gaseous hydrogen fluoride HF at 300-400°C [Chemical encyclopedia: 5 so, V.5 / Ed. Board: Zefirov NS (editor-in-chief) and others - M.: Great Russian encyclopedia, 1998, 783 S. (Article "Uranium fluorides", p.45)]. The disadvantage of this method is the low yield of products in a single stage process.

A known method of producing uranium tetrafluoride (prototype)based on the recovery of uranium hexafluoride UF6in the flame of a mixture of H2-F2[Chemical encyclopedia: 5 so, V.5 / Ed. Board: Zefirov NS (editor-in-chief) and others - M.: Great Russian encyclopedia, 1998. - 783 S. (Article "Uranium fluorides", p.45)]. The disadvantage of this method is the use of expensive reagents.

The objective of the present invention to provide an industrial method of producing uranium tetrafluoride.

The problem is solved in that tetraploid uranium is produced by interaction of octaoxide truran with pairs decomposition of ammonium fluoride taken in excess 100-130% molar of the stoichiometric amount in the range of temperatures 260-700°C:

U3O8+12NH4F=3UF4+8H2 O+6N2+16H2

The reaction is recovered, the U6+to U4+and the translation of the oxide form of uranium in fluoride.

Example 1. In the reactor, heated to 300°C, serves octaoxide truran weight of 10 g and a couple of decomposition of ammonium fluoride, taken in an amount of 6.1, Get the powder mass 11,227 year, the product yield is 99,88%.

Example 2. Differs from Example 1 in that the reactor is heated to 400°C. to produce a powder mass 11,231 year, the product yield is 99.91 per cent.

Example 3. Differs from Example 1 in that the reactor is heated to 600°C. to produce a powder mass 11,217 year, the product yield is 99.79%.

The technical result is to reduce final product cost by eliminating the energy consumption for recovering uranium oxide and reducing the number of stages of processing.

The method of producing uranium tetrafluoride, including the recovery of uranium compounds, characterized in that as the uranium-containing compounds used octaoxide truran, recovery and fluoridation of octaoxide truran lead pairs decomposition of ammonium fluoride taken in excess 100-130 mol.% of the stoichiometric amount, in the temperature range 260-700°C.



 

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2 tbl, 2 ex

FIELD: chemistry.

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2 tbl, 1 ex

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FIELD: metallurgy.

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7 cl, 8 ex, 2 tbl

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2 cl, 1 ex, 1 tbl

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2 tbl

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1 ex

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EFFECT: the invention allows extract uranium hexafluoride from steel containers of any volume filled in with uranium hexafluoride irrespective of the share of uranium isotope 235.

4 cl, 2 ex

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