Selective detection of iodinated hydrocarbons by the electron capture detector with negative ion hydration and photodetachment

An electron capture detector (ECD) is described that responds sensitively to trace levels of iodinated hydrocarbons but does not respond to chlorinated hydrocarbons (ClHCs). These response characteristics have been achieved through control of four gas-phase processes: dissociative electron capture (EC) by the halogenated hydrocarbons, the regeneration of an EC-active species (thought to be HI) by the recombination of I{sup {minus}} with positive ions, the photodetachment (PD) of I{sup {minus}}, and the prevention of PD of Cl{sup {minus}} by the clustering of this negative ion by water molecules. This photodetachment-modulated electron capture detector (PDM-ECD) is instrumentally simpler than an earlier version. Its light source is a low-power Hg arc lamp and requires no associated monochromator or light filters. The application of this instrument to the specific detection of methyl and ethyl iodide in an air sample that contains an excess of ClHCs is demonstrated. The device is also shown to hold considerable promise for the selective detection of brominated hydrocarbons in the presence of ClHCs.

[1]  E. P. Grimsrud,et al.  Thermal electron detachment rate constants for azulene− at atmospheric pressure by the photodetachment-modulated electron capture detector , 1989 .

[2]  E. P. Grimsrud,et al.  Electron capture chemistry of CBrCl3 at atmospheric pressure by mass spectrometry and the photodetachment-modulated electron capture detector , 1989 .

[3]  Cheung,et al.  Comparison of experimental and calculated attachment rate constants for CFCl3 and CCl4 in the temperature range 294-500 K. , 1989, Physical review. A, General physics.

[4]  E. P. Grimsrud,et al.  Gas-phase electron photodetachment spectroscopy of the molecular anions of nitroaromatic hydrocarbons at atmospheric pressure , 1989 .

[5]  W. Seitz,et al.  Fluorescence study of organic cation binding to hydrocarbon-bonded silica surfaces , 1989 .

[6]  W. Rudolf Seitz,et al.  Poly(vinyl alcohol) as a substrate for indicator immobilization for fiber-optic chemical sensors , 1989 .

[7]  E. P. Grimsrud,et al.  Measurement of ion clustering equilibria of proton hydrates by atmospheric pressure ionization mass spectrometry , 1988 .

[8]  E. P. Grimsrud,et al.  The photodetachment-modulated pulsed electron capture detector. Iodide- and bromide-specific detection for the trace analysis of halocarbon mixtures. Photodetachment cross sections of the halides , 1988 .

[9]  N. Adams,et al.  Studies of dissociative electron attachment to the free radicals CCl3 and CCl2Br using the FALP apparatus , 1988 .

[10]  Shinichi Yamabe,et al.  Solvation of halide ions with water and acetonitrile in the gas phase , 1988 .

[11]  N. Adams,et al.  Studies of the reactions HBr(HI)+e to or from Br-(I-)+H using the FALP and SIFT techniques , 1987 .

[12]  K. Jennings.  Gas Phase Ion Chemistry, Vol. 3: Ions and Light : Edited by Michael T. Bowers, Academic Press, New York, 1984. ISBN 0-12-120803-6, Price: $75.00/£58.00. , 1985 .

[13]  J. I. Brauman,et al.  Gas-Phase Ion Chemistry , 1985, Science.

[14]  E. P. Grimsrud.  Effect of positive ion/molecule reactions on the response of the electron capture detector to anthracene , 1984 .

[15]  C. R. Martin,et al.  Luminescence Titrations of Polyelectrolytes. , 1984 .

[16]  N. Adams,et al.  Attachment coefficients for the reactions of electrons with CCl4, CCl3F, CCl2F2, CHCl3, Cl2 and SF6 determined between 200 and 600 K using the FALP technique , 1984 .

[17]  J. Mcgowan,et al.  Physics of ion-ion and electron-ion collisions. Vol. 83 , 1983 .

[18]  C. Lochmüller,et al.  The effect of end-capping reagent on liquid chromatographic performance , 1982 .

[19]  W. Rudolf Seitz,et al.  pH sensor based on immobilized fluoresceinamine , 1982 .

[20]  W. B. Knighton,et al.  Response of an electron capture detector to methyl iodide , 1982 .

[21]  C. Lochmüller,et al.  An examination of chemically-modified silica surfaces using fluorescence spectroscopy , 1981 .

[22]  E. Chen,et al.  Chapter 3 Theory of electron capture , 1981 .

[23]  C. Poole,et al.  Electron capture: Theory and practice in chromatography , 1981 .

[24]  P. Patterson.  Pulse-modulated electron capture detection with nitrogen carrier gas , 1977 .

[25]  A. Mandl.  Electron photodetachment cross sections ofCl−andBr− , 1976 .

[26]  G. Royer,et al.  Immobilization of enzymes on aldehydic matrices by reductive alkylation. , 1975, Biochemical and biophysical research communications.

[27]  J. Warman,et al.  An investigation of electron thermalization in irradiated gases using CCl4 as an electron energy probe , 1975 .

[28]  A. Mandl,et al.  Direct Observation of an Autodetaching State of I , 1973 .

[29]  G. Davis.  Dansylglycine as a fluorescent probe for aqueous solutions of cationic detergents , 1972 .

[30]  M. Arshadi,et al.  Hydration of the halide negative ions in the gas phase. II. Comparison of hydration energies for the alkali positive and halide negative ions , 1970 .

[31]  A. S. Kertes,et al.  Ion exchange and solvent extraction of metal complexes , 1969 .