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
Email: schalk@unf.edu
Website: @unf

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Organic compound

Classification: Organic compound -> chloroform

Citations 3

"Vapor Generation Fourier Transform Infrared Spectrometry. A New Analytical Technique"
Anal. Chim. Acta 1995 Volume 308, Issue 1-3 Pages 28-35
Emilio López-Anreus, Salvador Garrigues and Miguel De La Guardia

Abstract: A single channel manifold for the generation of vapors for FTIR measurements is described. The liquid samples were injected into an electrically heated Pyrex glass reactor of 2.5 mL volume and evaporated at a controlled temperature. The vapors were then into the IR gas cell by a N2 carrier gas. The methodology was adapted to determine ethanol in CHCl3. A sample volume of 25 µL was injected into the reactor which was maintained at 90°C. The N2 carrier gas at 410 ml/min swept the volatiles into the detector cell where the absorbance peaks of ethanol and CHCl3 at 1066 and 931 cm-1, respectively, were monitored. A linear calibration graph was obtained (range not given) and the detection limit for ethanol in CHCl3 was 0.02% (v/v). The results obtained for the analysis of commercial samples of CHCl3 stabilized with ethanol were comparable to those produced by a reference procedure based on flow injection - NIR analysis.
Ethanol Spectrophotometry Gas phase detection Method comparison Volatile generation Volatile generation

"Near Infrared Detection Of Flow Injection Analysis By Acousto-optic Tunable Filter-based Spectrophotometry"
Anal. Chem. 1996 Volume 68, Issue 6 Pages 971-976
Mauricio S. Baptista, Chieu D. Tran, and Guan-Hong Gao

Abstract: A NIR spectrometer which can serve as a sensitive and universal detector for FIA is described. It included a solid-state acousto-optic tunable filter (AOTF) which allowed a high scanning speed and wavelength accuracy. Collimated incident light was dispersed to monochromatic and spectrally scanned by the AOTF. The diffracted light was split into sample and reference beams, with a flow cell placed in the sample beam. Light intensities were detected by thermoelectrically cooled GaInAs detectors and the signals were amplified and passed to a microcomputer. The recorded spectra were subjected to multivariate calibration methods. The instrument was applied to the determination of water traces in CHCl3 and benzene and water in ethanol. The instrumentation development of a near-infrared (near-IR) spectrophotometer based on an acoustooptic tunable filter (AOTF) and its application as a detector for flow injection analysis (FIA) are reported. In addition to being compact and all solid state, this AOTF- based instrument is very sensitive, has high resolution, and can be rapidly scanned. The latter advantage make it uniquely suited as a detector for FIA, in that it can rapidly record the whole near-IR absorption spectrum of a mixture passing through the FIA flow cell. Subsequent treatment of the recorded spectra with multivariate calibration methods makes it possible to use the FIA, for the first time, for such applications as the simultaneous determination of trace amounts of water and benzene in ethanol. Because all organic compounds absorb light in the near-infrared region, this AOTF-based near-IR detector can serve as a universal detector for FIA; as a consequence, applications of the FIA techniques can be expanded to other areas which are not possible otherwise.
Water Benzene Spectrophotometry Acousto optic tunable filter Computer Multivariate calibration

"Flow Injection Near-infrared Determination Of Ethanol In Chloroform"
Fresenius J. Anal. Chem. 1995 Volume 351, Issue 8 Pages 724-728
Emilio López-Anreus, Salvador Garrigues and Migue de la Guardia

Abstract: Chloroform (300 µL) was injected into a carrier stream (1.35 ml/min) of CHCl3 stabilized with pentene and the absorbance was measured by NIR spectrometry at 2272 nm. A reference sample of CHCl3 stabilized with pentene was used. The dynamic range of the method was upto 10% ethanol with a detection limit of 0.0045%. The RSD was 0.4% for 1% ethanol.
Ethanol Spectrophotometry