ANALYSIS OF SOLVENT RECOVERED FROM WRIGHT INDUSTRIES, INCORPORATED TESTING

摘要

Washington Savannah River Company (WSRC) began designing and building a Modular Caustic Side Solvent Extraction (CSSX) Unit (MCU) at the Savannah River Site (SRS) to process liquid waste for an interim period. The MCU Project Team conducted testing of the contactors, coalescers, and decanters at Wright Industries, Incorporated (WII) in Nashville, Tennessee. That testing used MCU solvent and simulated SRS dissolved salt. Because of the value of the solvent, the MCU Project wishes to recover it for use in the MCU process in the H-Tank Farm. Following testing, WII recovered approximately 62 gallons of solvent (with entrained aqueous) and shipped it to SRS. The solvent arrived in two stainless steel drums. The MCU Project requested SRNL to analyze the solvent to determine whether it is suitable for use in the MCU Process. SRNL analyzed the solvent for Isopar{reg_sign} L by Gas Chromatography--Mass Spectroscopy (GC-MS), for Modifier and BOBCalixC6 by High Pressure Liquid Chromatography (HPLC), and for Isopar{reg_sign} L-to-Modifier ratio by Fourier-Transform Infrared (FTIR) spectroscopy. They also measured the solvent density gravimetrically and used that measurement to calculate the Isopar{reg_sign} L and Modifier concentration. The conclusions from this work are: (1) The constituents of the used WII solvent are collectively low in Isopar{reg_sign} L, most likely due to evaporation. This can be easily corrected through the addition of Isopar{reg_sign} L. (2) Compared to a sample of the WII Partial Solvent (without BOBCalixC6) archived before transfer to WII, the Reworked WII Solvent showed a significant improvement (i.e., nearly doubling) in the dispersion numbers for tests with simulated salt solution and with strip acid. Hence, the presence of the plasticizer impurity has no detrimental impact on phase separation. While there are no previous dispersion tests using the exact same materials, the results seem to indicate that the washing of the solvent gives a dispersion benefit. (3) WII Solvent that underwent a cleaning cycle provides an acceptable set of cesium distribution (i.e., D) values when used in a standard Extraction, Scrub, and Strip (ESS) test.