Purex Diluent Chemical Degradation

TLDR: In this article, the chemical degradation of normal paraffin hydrocarbon diluents both in the pure state and mixed with 30% tributyl phosphate (TBP) was investigated in a series of experiments.

Abstract: The chemical degradation of normal paraffin hydrocarbon (NPH) diluents both in the pure state and mixed with 30% tributyl phosphate (TBP) was investigated in a series of experiments. The results show that degradation of NPH in the TBP-NPH-HNO/sub 3/ system is consistent with the active chemical agent being a radical-like nitrogen dioxide (NO/sub 2/) molecule, not HNO/sub 3/ as such. Spectrophotometric, gas chromatographic, mass spectrographic, and titrimetric methods were used to identify the degradation products, which included alkane nitro and nitrite compounds, alcohols, unsaturated alcohols, nitro alcohols, nitro alkenes, ketones, and carboxylic acids. The degradation rate was found to increase with increases in the HNO/sub 3/ concentration and the temperature. The rate was decreased by argon sparing to remove NO/sub 2/ and by the addition of butanol, which probably acts as a NO/sub 2/ scavenger.