Gas Chromatography-Optical Fiber Detector for the Speciation of Aromatic Hydrocarbons in Confined Areas

Abstract

An analytical method, based on separation with gas chromatography (GC) and detection with optical fiber (OF), was used for the separation, detection and quantification of benzene, toluene, ethylbenzene, p-xylene, m-xylene and o-xylene. The use of OF as a detector is based on the variations of the reflected optical power detected when the aromatic compounds eluted from the GC column are sorbed in a thin polymeric film on a single-mode OF. General figures of merit, such as the analytical time, analytical error and analytical performance of GC-OF were similar to those of the classical analytical methods, such as a gas chromatography-flame ionization detector (GC-FID). However, the developed GC-OF method constitutes a much less expensive alternative for the speciation of aromatic hydrocarbons compounds, with high accuracy, and being most suitable for actual monitoring work on confined environments.

Optical fiber based methodology for assessment of thiocyanate in seawater

“…1b). The changes in the reflected optical power caused by variations in the OF refractive index have been previously discussed by Silva et al, [13][14][15][16][17][18][19][20][21][22][23] and depend on the coating film (PEG) and analyte properties, as well as the chemical interactions which can take place between these two elements. The mobile phase was 300 mM sodium sulfate and 50 mM sodium chloride and the flow-rate was 1.0 mL min À1 .…”

“…Optical fiber (OF) sensors and OF based methodologies have been proven to be of high sensitivity and of easy operation for several analytes. [13][14][15][16][17][18][19][20][21][22][23][24][25][26] In OF sensors based on polymeric film as…”

Optical fibre-based methodology for screening the effect of probiotic bacteria on conjugated linoleic acid (CLA) in curdled milk

“…1b). The changes in the reflected optical power caused by variations in the refractive index of optical fibre have been previously discussed by Silva, Rocha-Santos, and Duarte (2008a, 2008b, 2008c, 2008d and Silva, M-Costa, Freitas, Rocha-Santos, and Duarte (2009), and depend on both coating film (PDMS) and analytes (oleic acid methyl ester, linoleic acid methyl ester and CLA methyl ester) properties, as well as the chemical interactions which can take place between these two elements. The different sensitivities (Fig.…”

Automatic Optical Measurement and Control of Benzene and Benzenoids in Natural Gas Pipelines

“…Some studies have been devoted to the search of methods of analysis responding to the demand of sensors that are portable, low cost, and applicable to different circumstances [6]. Most of the apparatus are based on electrochemical [7] and metal oxide sensors, micro-gas chromatographs (µGC) [8], or electronic noses [9,10] with variable limit of detection (generally quite low) but with significant problems in calibration and selectivity. Detection methods for the measurement of benzene and benzenoids have been based on AAS (atomic absorption spectroscopy) [11] or by applying infrared spectroscopy [12].…”