Award Date


Degree Type


Degree Name

Master of Science (MS)



First Committee Member

Klaus J. Stetzenbach

Number of Pages



In this study, a GC analytical method for the determination of the ground water tracer, 2,6-difluorobenzoic acid (2,6-DFBA) at the part per billion level was established. Three sample preparation methods, which include two methylation methods and one silylation method, have been evaluated. Chromatographic instruments including GC/MS, GC/ECD, and GC/FID have been used. Silylation of 2,6-DFBA combined with GC/MS analysis has proven to be the best method in this study, due to the low detection limits (part per trillion) achieved, and the stability of the 2,6-DFBA silyl derivative. A GC/MS instrument calibration curve was established, a C-well water sample was analyzed with this method and results were compared with HPLC analysis which has been used to analyze 2,6-DFBA at the part per billion level in ongoing studies; Since the GC/MS has the ability to separate the silyl derivatives of the various difluorobenzoate isomers, several difluorobenzoates can be analyzed simultaneously by this method in cases where multiple tracers are needed. More work should be done towards achieving better extraction efficiency and reducing the sample preparation time.


Acid; Determination; Difluorobenzoic Ground; Ms; Tracer; Water

Controlled Subject

Chemistry, Analytic; Environmental engineering

File Format


File Size

1904.64 KB

Degree Grantor

University of Nevada, Las Vegas


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