Total cyanide analysis of tank core samples: Analytical results and supporting investigations. Revision 1
The potential for a ferrocyanide explosion in Hanford site single-shelled waste storage tanks (SSTS) poses a serious safety concern. This potential danger developed in the 1950s when {sup 137}Cs was scavenged during the reprocessing of uranium recovery process waste by co-precipitating it along with sodium in nickel ferrocyanide salt. Sodium or potassium ferrocyanide and nickel sulfate were added to the liquid waste stored in SSTs. The tank storage space resulting from the scavenging process was subsequently used to store other waste types. Ferrocyanide salts in combinations with oxidizing agents, such as nitrate and nitrite, are known to explode when key parameters (temperature, water content, oxidant concentration, and fuel [cyanide]) are in place. Therefore, reliable total cyanide analysis data for actual SST materials are required to address the safety issue. Accepted cyanide analysis procedures do not yield reliable results for samples containing nickel ferrocyanide materials because the compounds are insoluble in acidic media. Analytical chemists at Pacific Northwest Laboratory (PNL) have developed a modified microdistillation procedure (see below) for analyzing total cyanide in waste tank matrices containing nickel ferrocyanide materials. Pacific Northwest Laboratory analyzed samples from Hanford Waste Tank 241-C-112 cores 34, 35, and 36 for total cyanide content using technical procedure PNL-ALO-285 {open_quotes}Total Cyanide by Remote Microdistillation and Agrentometric Titration,{close_quotes} Rev. 0. This report summarizes the results of these analyses along with supporting quality control data, and, in addition, summarizes the results of the test to check the efficacy of sodium nickel ferrocyanide solubilization from an actual core sample by aqueous EDTA/en to verify that nickel ferrocyanide compounds were quantitatively solubilized before actual distillation.
- Research Organization:
- Pacific Northwest National Lab. (PNNL), Richland, WA (United States)
- Sponsoring Organization:
- USDOE, Washington, DC (United States)
- DOE Contract Number:
- AC06-76RL01830
- OSTI ID:
- 10141683
- Report Number(s):
- PNL-8858-Rev.1; ON: DE94009844; TRN: 94:007596
- Resource Relation:
- Other Information: PBD: Mar 1994
- Country of Publication:
- United States
- Language:
- English
Similar Records
Ferrocyanide Safety Project: FY 1991 annual report
Ferrocyanide safety program cyanide speciation studies FY 1993 annual report
Related Subjects
12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE WASTES FROM NUCLEAR FACILITIES
CYANIDES
QUANTITATIVE CHEMICAL ANALYSIS
IRON COMPOUNDS
HIGH-LEVEL RADIOACTIVE WASTES
SAFETY ANALYSIS
NICKEL
HANFORD RESERVATION
054000
052002
HEALTH AND SAFETY
WASTE DISPOSAL AND STORAGE