Reduction of Neptunium In Synthetic High Level Liquid Waste

International Congress on Energy 2011
2011 AIChE Annual Meeting
AIChE Annual Meeting
October 18, 2011 - 8:00pm

High-level liquid waste (HLLW), which is produced from reprocessing of the spent nuclear fuel and contains actinides, 90Sr, 137Cs, 99Tc, 129I, etc., engenders permanent hazard to environment. The safe treatment and disposal of HLLW are crucial to sustainable development of nuclear energy. The TRPO (a mixed trialkylphosphine oxide, commercial name Cyanex 923) process for removal actinides from HLLW has been studied in our laboratory since 1980s. In the TRPO process, the control of the oxidation states and the removal of Neptunium is one of the important problems. Neptunium has three readily accessible oxidation states, IV, V and VI, which can coexist under certain conditions. Therefore, careful control of Np chemistry is needed. There are lots of studies on Np chemistry in the ambience of nitric acid, perchloric acid, or other aqueous solutions. However, there is few study on Np chemistry in the HLLW, which contains lots of different salts.

In this work, we studied the reduction of Neptunium in synthetic HLLW to maintain its oxidation state at IV so that it can be extracted by TRPO and removed from the HLLW. Different reductants were tested and the kinetic of the reduction action was studied. The influence of the elements in HLLW was also studied. The reduction speed of Np was highly enhanced by some elements in the HLLW. Finally, a hybrid reductant was suggested and good reduction effect was obtained.

Professional Development Hours
0.5 PDHs
You will be able to download and print a certificate for these PDH credits once the content has been viewed. If you have already viewed this content, please click here to login.

Would you like to access this content?

No problem. You just have to complete the following steps.

You have completed 0 of 2 steps.

  1. Log in

    You must be logged in to view this content. Log in now.

  2. Purchase Technical Presentation

    You must purchase this technical presentation using one of the options below.
    If you already purchased this content recently, please click here to refresh the system's record of ownerships.


Credits 0.5 Use credits
List Price $25.00 Buy now
AIChE Members $15.00 Buy now
AIChE Undergraduate Student Members Free Free access
AIChE Graduate Student Members $15.00 Buy now
Related Topics: