ANALYSIS OF OILS USING FLUORESCENCE.
15
range of fluorophores as evidenced by the spread of high intensity contours into more of
the parameter space.
The large degree of similarity between some of the TSFS plots is largely due to the
fact that normalisation was done at the point of maximum fluorescence intensity and this
obscures the huge differences in fluorescence intensity observed for the various samples
(~200 fold between light (A) and heavy oils (I)).
50
3.7. Instrumentation
The instrumentation for laboratory based fluorescence analysis of petroleum fluids is
not that significantly different from that employed for routine biophysical or chemical
physics measurements. In the author’s laboratory at NUI-Galway, standard fluorescence
steady-state instrumentation (Perkin-Elmer LS50B) and time-resolved instrumentation
(TCSPC instrumentation assembled from commercial components) has been used. Apart
from using front-surface excitation for all measurements, there are no significant novel
requirements.
10, 21, 22, 23, 32, 50 Most of the novel instrumentation research involves the
development of systems for specific applications. Examples include using fibre optics
coupled with fluorescence and reflectivity measurements for quantifying the amounts of
oil, water, and gas in a continuous flow,
51, 52 and fibre optic systems for the analysis of
solid materials particularly from core samples,
53 and soil (or water).
54, 55 Several studies
have discussed the utility of various excitation sources, such as tuneable dye lasers
56 and
LED’s
57, 58 for oil fluorescence applications.
4. QUALITATIVE AND QUANTITATIVE OIL ANALYSIS
The use of fluorescence methods for the qualitative and quantitative analysis of
crude oils is fairly common, covering diverse applications from oil spill identification to
the study of microscopic petroleum fluid inclusions within rocks. The correlation of
different fluorescence parameters with chemical (or physical) characteristics of bulk
crude oils have been used to develop qualitative or quantitative models for industrial or
research applications. The selection (or indeed discovery) or the best fluorescence
parameters for quantitative crude oil analysis is a complex issue and has not yet been
fully resolved. One of the key challenges however, is to develop a method that is suitable
for any crude oil type from any source. In this section, we survey the use of both steadystate and time-resolved fluorescence parameters for the analysis of crude oils.
15
range of fluorophores as evidenced by the spread of high intensity contours into more of
the parameter space.
The large degree of similarity between some of the TSFS plots is largely due to the
fact that normalisation was done at the point of maximum fluorescence intensity and this
obscures the huge differences in fluorescence intensity observed for the various samples
(~200 fold between light (A) and heavy oils (I)).
50
3.7. Instrumentation
The instrumentation for laboratory based fluorescence analysis of petroleum fluids is
not that significantly different from that employed for routine biophysical or chemical
physics measurements. In the author’s laboratory at NUI-Galway, standard fluorescence
steady-state instrumentation (Perkin-Elmer LS50B) and time-resolved instrumentation
(TCSPC instrumentation assembled from commercial components) has been used. Apart
from using front-surface excitation for all measurements, there are no significant novel
requirements.
10, 21, 22, 23, 32, 50 Most of the novel instrumentation research involves the
development of systems for specific applications. Examples include using fibre optics
coupled with fluorescence and reflectivity measurements for quantifying the amounts of
oil, water, and gas in a continuous flow,
51, 52 and fibre optic systems for the analysis of
solid materials particularly from core samples,
53 and soil (or water).
54, 55 Several studies
have discussed the utility of various excitation sources, such as tuneable dye lasers
56 and
LED’s
57, 58 for oil fluorescence applications.
4. QUALITATIVE AND QUANTITATIVE OIL ANALYSIS
The use of fluorescence methods for the qualitative and quantitative analysis of
crude oils is fairly common, covering diverse applications from oil spill identification to
the study of microscopic petroleum fluid inclusions within rocks. The correlation of
different fluorescence parameters with chemical (or physical) characteristics of bulk
crude oils have been used to develop qualitative or quantitative models for industrial or
research applications. The selection (or indeed discovery) or the best fluorescence
parameters for quantitative crude oil analysis is a complex issue and has not yet been
fully resolved. One of the key challenges however, is to develop a method that is suitable
for any crude oil type from any source. In this section, we survey the use of both steadystate and time-resolved fluorescence parameters for the analysis of crude oils.