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Title: Speciation of methylmercury and ethylmercury by gas chromatography cold vapor atomic fluresence spectroscopy

Abstract

Existing models and simulants of tank disposition media at SRS have presumed the presence of high concentrations of inorganic mercury. However, recent quarterly tank analyses show that mercury is present as organomercurial species at concentrations that may present challenges to remediation and disposition and may exceed the Saltstone Waste Acceptance Criteria (WAC). To-date, methylmercury analysis for Savannah River Remediation (SRR) has been performed off-site by Eurofins Scientific (Lancaster, PA). A series of optimization and validation experiments has been performed at SRNL, which has resulted in the development of on-site organomercury speciation capabilities using purge and trap gas chromatography coupled with thermal desorption cold vapor atomic fluorescence spectroscopy (P&T GC/CVAFS). Speciation has been achieved for methylmercury, with a method reporting limit (MRL) values of 1.42 pg for methylmercury. Results obtained by SRNL from the analysis of past quarterly samples from tanks 21, 40, and 50 have demonstrated statistically indistinguishable concentration values compared with the concentration data obtained from Eurofins, while the data from SRNL has demonstrated significantly improved precision and processing time.

Authors:
 [1]
  1. Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)
Publication Date:
Research Org.:
Savannah River Site (SRS), Aiken, SC (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1395978
Report Number(s):
SRNL-L4100-2017-00014
TRN: US1800077
DOE Contract Number:
DE-AC09-08SR22470
Resource Type:
Technical Report
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; FLUORESCENCE SPECTROSCOPY; METHYLMERCURY; MERCURY; TANKS

Citation Formats

Boggess, A. Speciation of methylmercury and ethylmercury by gas chromatography cold vapor atomic fluresence spectroscopy. United States: N. p., 2017. Web. doi:10.2172/1395978.
Boggess, A. Speciation of methylmercury and ethylmercury by gas chromatography cold vapor atomic fluresence spectroscopy. United States. doi:10.2172/1395978.
Boggess, A. 2017. "Speciation of methylmercury and ethylmercury by gas chromatography cold vapor atomic fluresence spectroscopy". United States. doi:10.2172/1395978. https://www.osti.gov/servlets/purl/1395978.
@article{osti_1395978,
title = {Speciation of methylmercury and ethylmercury by gas chromatography cold vapor atomic fluresence spectroscopy},
author = {Boggess, A.},
abstractNote = {Existing models and simulants of tank disposition media at SRS have presumed the presence of high concentrations of inorganic mercury. However, recent quarterly tank analyses show that mercury is present as organomercurial species at concentrations that may present challenges to remediation and disposition and may exceed the Saltstone Waste Acceptance Criteria (WAC). To-date, methylmercury analysis for Savannah River Remediation (SRR) has been performed off-site by Eurofins Scientific (Lancaster, PA). A series of optimization and validation experiments has been performed at SRNL, which has resulted in the development of on-site organomercury speciation capabilities using purge and trap gas chromatography coupled with thermal desorption cold vapor atomic fluorescence spectroscopy (P&T GC/CVAFS). Speciation has been achieved for methylmercury, with a method reporting limit (MRL) values of 1.42 pg for methylmercury. Results obtained by SRNL from the analysis of past quarterly samples from tanks 21, 40, and 50 have demonstrated statistically indistinguishable concentration values compared with the concentration data obtained from Eurofins, while the data from SRNL has demonstrated significantly improved precision and processing time.},
doi = {10.2172/1395978},
journal = {},
number = ,
volume = ,
place = {United States},
year = 2017,
month = 9
}

Technical Report:

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