Mercury speciation in liquid petroleum product : comparison between on-site approach and lab measurement using size exclusion chromatography with high resolution inductively coupled plasma mass spectrometric detection (SEC-ICP-HR MS)

• Published in: Fuel processing technology Vol. 131
• Main Authors: Gaulier, Florine, Gibert, Alexandre, Walls, David, Langford, Michael, Baker, Stuart, Baudot, Arnaud, Porcheron, Fabien, Lienmann, Charles-Philippe
• Format: Journal Article
• Language: English
• Published: Elsevier 24.03.2015
• Subjects: Chemical Sciences; ICP/MS; Mercury; Speciation; Hg; Liquid petroleum
• ISSN: 0378-3820; 1873-7188
• DOI: 10.1016/j.fuproc.2014.10.024

The accuracy of two different analytical methods dedicated to the speciation of mercury in liquid hydrocarbons isdiscussed in the present paper. A first step involving the comparison of a modified UOP 938 method—based onfiltration, purge and extraction—with size exclusion chromatography coupled to ICP-HR MS (SEC-ICP-HR MS)was carried out on specific synthetic model mercury compounds. The modified UOP 938 method (defined hereas operational speciation) allowed various mercury compounds to be grouped into different families, i.e. particulate,volatile, ionic and organic non-ionic mercury,whereas SEC-ICP-HRMS provided size distribution profiles ofmercury-containing molecules. In a second step, comparison of the two different approaches was then performedwith real hydrocarbon feeds, such as crude oil, condensate and straight-run gasoline samples. Itwas demonstratedthat even though elemental Hg was present for the North Sea condensate, all of them contained ionic Hgassociated to molecules containing few to many tens of carbon atoms.