Aralex process

The presence of DTPA should prevent the formation of plutonium polymer during the transition from pH = 9 to less than pH = 0.3. Above 1 M in hydrogen ion concentration, H5DTPA is no longer very effective as a chelating agent and thus does not affect the Dfs of actinides in the ARALEX process. In addition, DTPA in the Na2C03 scrub also prevents the formation of plutonium hydroxide when macro concentrations of plutonium are present. 

The ARALEX process can also be used to extract detergents from aqueous solutions containing actinides for example, contaminated laundry solutions. Detergents from all three classes (anionics such as alkyl sulfates and alkyl benzene sulfonates cationics such as N-benzyl-N-alkyl dimethyl ammonium chloride and nonionics such as polyoxyethylenated alkyl phenols) are... 

In addition, the ARALEX process can be used to scrub residual TBP from various product streams such as americium and curium nitrate solutions, thus preventing the eventual precipitation of phosphates. The D s for TBP from dilute (0.17 to) to concentrated (8 M) HNO3 solutions using 2-EHOH are in the range of 8 x 103 to 5 x 103, respectively, at 25°C and 50°C. 

The ARALEX process is relatively simple and involves inexpensive and readily available chemicals. The ARALEX process can also be applied to other actinide waste streams which contain appreciable concentrations of polar organic compounds that interfere with conventional actinide ion exchange and liquid-liquid extraction procedures. One such application is the removal of detergents from laundry or clean-up solutions contaminated with actinides. 

This paper describes a process for the recovery of actinides from Na2C03 scrub waste solutions which involves the extraction of the HDBP and H2MBP from acidified solutions using a water-immiscible aliphatic alcohol. All the actinides remain in the aqueous phase, which may then be processes using conventional TBP or DHDECMP procedures (3). We refer to this process as the ARALEX (Argonne alcohol extraction) process. This paper also describes the extraction equilibria measurements performed in the development of the process. 

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