University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Website: @unf

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Classification: Oil -> fuel

Citations 6

"Development Of A Selective Post-column Detector For Phenols Separated By High Performance Liquid Chromatography"
Anal. Chim. Acta 1987 Volume 192, Issue 2 Pages 277-287
S. K. Ratanathanawongs and S. R. Crouch

Abstract: Samples are injected into the HPLC system for separation followed by UV detection at 254 nm. The column eluate is passed to an air-segmented continuous-flow system and mixed with diazotized sulfanilic acid, and the azo-derivatives are detected at 450 nm. The aqueous reaction system was compatible with reversed-phase mobile phases. Band-broadening (caused by the post-column reactor) was observed, following optimization, to be between 5 and 20%. A rectilinear response from 0.071 to 14 µg mL-1 of phenol was obtained. The system was demonstrated by the analysis of river water containing phenol, aniline, o-cresol and 3,5-xylenol and of residual fuel oil fractions containing phenol and o-cresol.
Phenol Aniline 2-Cresol Xylenol HPLC Spectrophotometry Optimization Post-column derivatization

"Flow Injection Titration-linear Or Logarithmic"
Talanta 1994 Volume 41, Issue 6 Pages 949-955
R. Chen, J. Ruzicka* and G. D. Christian,

Abstract: The single-line FIA system of Taylor et al. (cf. Ibid., 1992, 39, 789) for flow injection coulometric titration was modified (described and illustrated). Organic solvent was loaded into the sample loop and injected into the mixing chamber by Karl Fischer reagent, the flow was stopped at an appropriate dilution and current was applied for a given period. The mixing chamber was flushed with the Karl Fischer reagent. A graph of titration time vs. water content in ethanol or methanol was linear up to 60 µL. For the determination of H2SO4 in oil refinery 'black acid' the mixing chamber was modified (details given) and flushed with 0.8155 M NaOH containing 0.04% bromothymol blue indicator before sample injection with 94.7 mM NaOH containing 0.04% indicator. NaOH was pumped at a constant rate for a given period and the absorbance was monitored until the indicator changed from yellow to blue. A calibration graph of absorbance vs. log. H2SO4 concentration was linear up to 1.98% wt. The coulometric method had good precision and linear calibration, whereas the continuous-flow method allowed rapid measurement with reasonable sensitivity; both techniques could be used for many applications.
Sulfuric acid Coulometry Spectrophotometry Karl Fischer analysis Stopped-flow Mixing chamber Titrations

"Continuous-flow High-field Nuclear Magnetic Resonance Detector For Liquid Chromatographic Analysis Of Fuel Samples"
Anal. Chem. 1981 Volume 53, Issue 14 Pages 2327-2332
James F. Haw, T. E. Glass, and H. C. Dorn

Abstract: The design and characterization of a continuous flow probe insert for a 200-MHz 1H nuclear magnetic resonance (NMR) detector for high-performance liquid chromatography (HPLC) are described. Modern superconducting magnet based systems present different requirements for flow probe design, but a considerable improvement over older spectrometers is readily achieved. Improvements in both spectroscoplc and chromatographic resolution are shown to enhance the analytical utility of LC-1H NMR. Spectral resolution is 2 Hz or 4 Hz with optimum sensitivity. Injection volumes of 10^-25 pL provide detection limits of 10 kg. The LC-1H NMR analyzes of a model mixture and two experimental petroleum based fuel samples are presented. A LC-IH NMR based method for calculating the average degree of substitution of aromatic ring systems is discussed in detail.
Nuclear magnetic resonance HPLC Apparatus Detector

"The Use Of Reference Materials In The Fossil Fuels Quality Control"
Microchim. Acta 1996 Volume 123, Issue 1-4 Pages 217-230
Maurizio Bettinelli, Sandro Spezia, Umberto Baroni and Gabriele Bizzarri

Abstract: Quality control procedures used for the determination of trace elements in fuel oil and coal are described. Two standard reference materials (NIST 1632a and 1632b) were used to evaluate the accuracy in the determination of As, Hg and Se in coal by flow injection (FI) hydride-generation (HG) AAS and FI HG ICP-MS after microwave solubilization (Anal. Chim. Acta, 1989, 225, 159). RSD over 2 years were 10% for As, 8.11% for Se and 15% for Hg. The use of real fuel oil samples to compare results obtained for the determination of Ni and V by NAA, ICP-MS, ETAAS and ICP-AES in 54 laboratories is discussed. Similarly, the use of real samples to detect significant bias in the determination of As, Hg and Se in coal using various techniques (NAA, FI HG AAS, FI HG ICP-MS, ETAAS) is discussed.
Trace elements Arsenic Mercury Selenium Nickel Vanadium Sample preparation Spectrophotometry Spectrophotometry Mass spectrometry Mass spectrometry Reference material Method comparison

"Flow Injection Analysis Of C-fuel Oil-contaminated Samples Based On The Fluorescence Detection Of Polycyclic Aromatic Hydrocarbons"
Anal. Sci. 1998 Volume 14, Issue 4 Pages 845-847
Akiko UTSUMI, Atsuko NAKASHIMA, Kyoko ANDO, Ryoichi KIZU and Kazuichi HAYAKAWA

Abstract: On Jan. 2, 1997, >6,000 kL of C-fuel, a fuel oil, was spilled in the Sea of Japan and drifted toward 8 Prefectural sea coasts from Shimane to Yamagata. Polycyclic arom. hydrocarbons were determined in the spilled oil, sea sand, and water using HPLC equipped with a fluorescence detector. Although the HPLC method was accurate and quant., it takes too much time for rapid anal. of many oil-polluted environmental samples. Thus, a flow injection analysis method was used as a rapid screening test of C-fuel oil pollution. Results using this method to analyze sea sand polluted with oil from this spill are also reported.
Polycyclic aromatic hydrocarbons Fluorescence

"Rapid Determination Of Dissolved Oxygen In A Three-component Flooding Oil System By Flow Injection Analysis"
Fenxi Huaxue 1994 Volume 22, Issue 1 Pages 74-76
Li, Y.M.;Chen, L.R.;Chen, Q.S.;Han, W.

Abstract: The construction of a FIA system is demonstrated by determination of dissolved O2 in fuel oil, based on the reaction of O2 with the leuco form of methylene blue (C. I. Basic Blue 9, I) to form a blue oxidation product. A 20 µL portion of the sample was injected into a colorless carrier stream (pH 7.5, 1 ml/min) of 0.0124% I and 0.065% glucose in 95% ethanol and the absorbance was measured at 647 nm. The calibration graph was linear from 0.08 (detection limit) to 8.35 µg/ml of O2. The RSD (n = 7) was 2.6%. Results agreed with those obtained by iodimetry.
Oxygen Spectrophotometry