Chemistty of the Purex Process

Abstract

Reprocessing!Purex ISolvent extraction /Nuclearfuel cycle SummaiyThe Purex process, used for recovering Pu and U from inadiated nuclear fuel, has had an outstanding record of safety and efficiency for nearly 30 years. The present status of process chemistry is reviewed and number of potential improvements are identified that should make the process even safer and more efficient in the future.

Following the electroreduction of uranium dioxide to uranium in LiCl–KCl eutectic in situ using synchrotron radiation

“…Spent nuclear fuel reprocessing has traditionally utilised a liquid-liquid extraction (LLE) process route for the separation of actinides, which has the notable drawback of poor proliferation resistance [2].…”

The effect of SO3-Ph-BTBP on stainless steel corrosion in nitric acid

“…Current measurements were then recorded from 0.5 to 1.5 V at a scan rate of 10 mVs -1 . All experiments are performed in 1.13 moldm -3 (5 wt%) HNO 3 . This concentration is slightly higher than that employed in the 2nd cycle TRU back-extraction in EURO-GANEX (0.8 moldm -3 ) [2], but representative of that found in the AHA extraction step in an advanced-PUREX process [7].…”

“…From head end to product fi nishing this fl ow sheet is broadly similar to the Plutonium Uranium Redox EXtraction (PUREX/advanced-PUREX) fl ow sheet [3][4][5][6][7], which is currently employed at the Thermal Oxide Reprocessing Plant (THORP) in the UK for the reprocessing of spent nuclear fuel. However, there are two key differences between the EURO-GANEX and PUREX process: 1) Di(2-ethyl hexyl) isobutyramide (DEHiBA) and odourless kerosene (OK) are deployed in the primary separation cycle and N,N,N′,N′-tetraoctyldiglycolamide (TODGA) and N,N′--dimethyl-N,N′-dioctylhexylethoxymalonamide (DMDOHEMA) in the 2nd cycle trans-uranium element extraction in the EURO-GANEX process to produce an impure, proliferation resistant, plutonium stream.…”

The effect of acetohydroxamic acid on stainless steel corrosion in nitric acid

“…It is based on the selective liquid/liquid extraction and separation of uranium and plutonium from nitric acid solutions of dissolved SNF by use of a tri-n-butylphosphate (TBP) extractant in odourless kerosene (OK) [1].…”