Method for stabilizing U(IV) valence state in TBP

A valence and stable technology, applied in nuclear engineering, radioactive purification, etc., can solve the problems of increased use of reagents, easy extraction, and reduced use of plutonium to remove uranium from plutonium.

Inactive Publication Date: 2016-09-07
CHINA INSTITUTE OF ATOMIC ENERGY
View PDF4 Cites 0 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

The oxidation of U(IV) to U(VI) will increase the amount of U(IV) reagent used, and the increase in the amount of U(IV) will also reduce the effect of removing uranium from plutonium
In order to solve this problem, the traditional method is to use hydrazine as a supporting reducing agent to scavenge nitrous acid to stabilize the valence state of U(IV), but there are the following problems: U(IV) can be partially extracted into TBP, and nitrous acid is more effective than U (IV) is easily extracted into TBP, but hydrazine is difficult to be extracted by TBP, so when hydrazine is used as a supporting reducing agent, it can only stabilize the valence state of U(IV) in the aqueous phase, and U(IV) in the organic phase is easily extracted into TBP Nitrite Oxidation in
[0003] In the current published literature, there is no report about how to stabilize the U(IV) valence state in the TBP extractant. Therefore, a method to solve this problem is urgently needed

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for stabilizing U(IV) valence state in TBP
  • Method for stabilizing U(IV) valence state in TBP

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0019] Use two parts of TBP-xylene solutions containing TBP volume fraction 10% to extract the purified U(IV) solution (total uranium concentration 3.09g / L, wherein U(IV) concentration 3.07g / L , purity ≥ 99.2%, nitric acid concentration is 1mol / L), divided into two groups, and all under the condition of 25 ℃, wherein the concentration of adding acetaldehyde oxime to the water phase of one group is 20mmol / L, another group of water The phase does not contain acetaldehyde oxime. After extraction, take out the organic phase, and measure the absorbance value of the organic phase in the range of 450-700 nm at regular intervals, and the valence stability of U(IV) can be investigated through the characteristic absorption peak of U(IV) in this region.

[0020] Experimental results such as figure 1 , 2 As can be seen from the above results, when there is no acetaldehydexime, the peak value of U(IV) in the organic phase has been significantly reduced after 2 hours, that is, U(IV) has b...

Embodiment 2

[0023] The difference from Example 1 is that acetaldehyde oxime is added to the organic phase at a concentration of 2 mmol / L. The temperature condition in this example was 40°C.

Embodiment 3

[0025] The difference from Example 1 is that acetaldehyde oxime is added to the organic phase at a concentration of 50 mmol / L. The temperature condition in this example was 5°C.

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention belongs to the technical field of after treatment of nuclear fuels, and discloses a method for stabilizing a U(IV) valence state in TBP. The method is implemented by introducing acetaldoxime into an organic phase of TBP; or introducing the acetaldoxime into a water phase, and then extracting the acetaldoxime into the organic phase of the TBP by a way of extraction, wherein the concentration of the acetaldoxime introduced into the organic phase of the TBP is 2-100mmol / L, and the concentration of the acetaldoxime introduced into the water phase is 20-1000mmol / L. The method has the advantages of being simple, and being capable of enabling the stabilization time of the U(IV) valence state in the TBP to be long.

Description

technical field [0001] The invention belongs to the technical field of nuclear fuel reprocessing, and in particular relates to a method for stabilizing the valence state of U(IV) in TBP. Background technique [0002] In the post-treatment Purex process, U(IV) is usually used as a reducing agent to reduce Pu(IV) which is easy to be extracted by TBP to Pu(III) which is difficult to extract, but U(IV) will be gradually absorbed by nitric acid and Nitrous acid is oxidized to U(VI), and the oxidation of nitrous acid is particularly obvious, which is mainly due to the fact that nitrous acid can accelerate the oxidation of U(IV) by autocatalysis. The oxidation of U(IV) to U(VI) will increase the usage of U(IV) reagent, and the increase of U(IV) usage will also reduce the effect of removing uranium from plutonium. In order to solve this problem, the traditional method is to use hydrazine as a supporting reducing agent to scavenge nitrous acid to stabilize the valence state of U(IV)...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
Patent Type & Authority Applications(China)
IPC IPC(8): G21F9/12
CPCG21F9/125
Inventor 左臣晏太红郑卫芳石四维
Owner CHINA INSTITUTE OF ATOMIC ENERGY
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products