DEVELOPMENT OF ANALYTICAL METHODS FOR DETERMINING SUPPRESSOR CONCENTRATION IN THE MCU NEXT GENERATION SOLVENT (NGS)

Taylor-Pashow, K. ; Fondeur, F. ; White, T. ; Diprete, D. ; Milliken, C.

关键词: NGS;    MCU;    TiDG;    guanidine;    titration;    NMR;   

DOI  :  10.2172/1089499
RP-ID  :  SRNL-STI-2013-00435
PID  :  OSTI ID: 1089499

学科分类：化学（综合）

美国|英语

来源: SciTech Connect

【 摘 要 】

Savannah River National Laboratory (SRNL) was tasked with identifying and developing at least one, but preferably two methods for quantifying the suppressor in the Next Generation Solvent (NGS) system. The suppressor is a guanidine derivative, N,N',N"-tris(3,7-dimethyloctyl)guanidine (TiDG). A list of 10 possible methods was generated, and screening experiments were performed for 8 of the 10 methods. After completion of the screening experiments, the non-aqueous acid-base titration was determined to be the most promising, and was selected for further development as the primary method. {sup 1}H NMR also showed promising results from the screening experiments, and this method was selected for further development as the secondary method. Other methods, including {sup 36}Cl radiocounting and ion chromatography, also showed promise; however, due to the similarity to the primary method (titration) and the inability to differentiate between TiDG and TOA (tri-n-ocytlamine) in the blended solvent, {sup 1}H NMR was selected over these methods. Analysis of radioactive samples obtained from real waste ESS (extraction, scrub, strip) testing using the titration method showed good results. Based on these results, the titration method was selected as the method of choice for TiDG measurement. {sup 1}H NMR has been selected as the secondary (back-up) method, and additional work is planned to further develop this method and to verify the method using radioactive samples. Procedures for analyzing radioactive samples of both pure NGS and blended solvent were developed and issued for the both methods.