Flame ionization detector for

Neumayr [3] has discussed methods for sampling soil atmospheres and gives a detailed account of gas chromatographic methods employing electron capture and flame ionization detectors for detecting and estimating specific components of the soil atmosphere. 

Analyses were done with a Perkin Elmer Model 900 gas chromatograph equipped with a flame ionization detector. For evaluation of the charcoal the gas chromatograph was fitted with a 3.0-m x 3 2-mm o.d. stainless steel column packed with 10 ... 

FIGURE 7.8 Temperature-programmed desorption (TPD) chromatograms (flame-ionization detector) for the acidic sites of magnesium silicate. (A) Total TPD after complete saturation (B) TPD after 64% partial saturation (C) TPD after 34% partial saturation and (D) TPD after 18% partial saturation. 

Liquid samples were taken with 2 ml syringes after 24 h and 48 h, to verify if equilibrium between adsorbed and bulk phase was achieved, and analyzed in a gas chromatograph with flame ionization detector. For eveiy binaiy mixture, a calibration line was obtained by analysis of the blank samples, for which the concentration of the components is exactly known. For each sample the amount adsorbed (qsotbaic) at equilibrium was obtained by calculation of the mass balance. 

To determine the residual concentration, the tubes were centrifuged to separate the solids. The centrifugate was then carefully decanted and diluted as appropriate. A 5 ml volume sample was then withdrawn from each vial and extracted with 5 ml of an appropriate solvent (iso-octane for p-DCB, and hexane for 2,4-DCP and NB) and the extract analyzed using a Hewlett-Packard 5B40-A gas chromatograph fitted with an electron capture detector for the p-DCB and the 2,4-DCP and a flame ionization detector for the NB. The resultant concentration versus time plots for p-DCB, 2,4-DCP, and NB on both soils, displayed in Figs. 1, 2, and 3,... 

B18. Braman, R. S., Flame emission and dual flame emission-flame ionization detectors for gas chromatography. Anal. Chem. 38, 734-742 (1966). 

All experiments were carried out in a t3fpical laboratory reactor consisting of quartz reactor tube loaded in a tube furnace. Flow rates and gas compositions were varied using mass flow controllers and the composition of the feeds and products were measured with a chemiluminescence detector for NOx and a flame ionization detector for total hydrocarbon. 

Products were collected and weighed to determine a mass balance. Except for two experiments, in which the volume of gases exceeded the capacity of the gas collection system and the last portion was vented, the mass balance ranged from 95 to 98% ( 14). We measured C, H, N, and acid-evolved CO2 content for all retorted shales and for some burnt shales from the cracking experiments. Oils were analyzed for C, H, and N. Gases were analyzed by gas chromatography (thermal conductivity detector for h2> CO2 N2, and CH4 flame ionization detector for... 

Zimmermann, S., Krippner, R, Vogel, A. and Muller J. (2002) Miniaturized flame ionization detector for gas chromatography. Sens Actual B, 83 (1-3), 285-289. 

Fig. 3.2. System for double-column chromatography with intermediate trapping and re-injection, suitable also for direct injection of aqueous solutions. 1, carrier gas 2, pressure regulator 3, flow controller 4, vent for back-flushing S, injection port for heart-cut and back-flushing 6, precolumn (packed) 7, injection port for aqueous solutions 8, control flame ionization detector for pre-separation 9, vent for cutting 10. leak for make-up gas 11, trap 12, outlet of splitter 13, glass capillary column 14, flame ionization detector for main separation. Reproduced from [35].

A typical gas arriving at the catalyst face contained 2.5% CO, 1000 ppm HC, 500 ppm NO, 3% 02, and 0.48 g Pb/hr (as tetraethyllead). Catalyst inlet and exit gas samples were monitored for HC by flame ionization detector, for CO by nondispersive IR analyzer, and for 02 by paramagnetic analyzer. The effect of the TEL poison on catalyst activity was monitored by measuring the decrease in CO and HC conversion levels. 

Carbon monoxide may be determined over a wide range of concentration via infrared analysis [25]. Good results are achieved at concentrations as low as 1.25 to 2.5 mg m . The main disadvantage of this technique is the non-linear response, as well as possible interference by CO2, water vapour and hydrocarbons. The use of the gas chromatography for determining CO includes a catalytic reduction system, which converts carbon monoxide quantitatively to methane and a flame ionization detector. For a rapid CO determination, indicator tubes with palladium salt as a catalyst and silicomolybdate complex, which yields a blue colour with carbon monoxide, are used. The CO determination can also be carried out on the basis of its reaction with the radioactive kryptonate of palladium chloride [18, 25]. 

The reaction products were periodically analyzed by Gas Chromatography using a Tenax GC column attached to a flame ionization detector. For the oxidation of toluene over VAPO-5, Mass Spectroscopy was also used to identify the byproducts formed at the beginning of the reaction. 

Catalytic experiments were carried out at atmospheric pressure in a gas flow microreactor widi He as a diluent. The gas concentrations (NO, CO, O2, hydrocarbons) have been chosen to be representative of the exhaust gas mixtures of spark ignition engines. Analysis were performed by gas chromatography with a dual column (porapak and molecular sieve) and a TCD detector for O2, N2, CO, CO2, N2O, and a flame ionization detector for hydrocarbons. NO and NO2 were analyzed on-line by IR spectrometry (Rosemount analyzers). 

In 1963, Karman and Guiffrida announced a similar effect which they had observed in flame ionization detectors for gas chromatography, when an alkali metal and phosphorus-containing compound were present in the flame simultaneously, and Page and Woolley showed that this effect, too, was the result of an increase in the electron level above that to be expected in the absence of acceptor. 

Crane, R. T., Goheen, S. C., Larking, E. C. et al (1983) Complexities in lipid quantitation using thin layer chromatography for separation and flame ionization detector for detection. Lipids, 18, 74-80. 

Sometimes, the sensitivity factor, approaches 1 (i.e., in gas chromatography using the flame ionization detector for reactions in which the number of carbon atoms is not changed or in liquid chromatography using ultraviolet detection for reactions in which the absorption center is not involved). 

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