Flame ionization detector operation

The flame ionization detector operates by blending the column effluent with H2 and burning it with air in an.ionizing flame. The ions are... 

The price of a column ( 200 to 800) may be viewed as relatively small compared to the initial, routine, and preventive maintenance costs of the instrument. In fact, a laboratory may find that the cost of a set of air and hydrogen gas cylinders of research-grade purity for FID (flame ionization detector) operation is far greater than the price of a single conventional capillary colunm Consequently, to derive maximum performance from a gas chromatographic system, the colunm should be carefully selected for an application, handled with care following the suggestions of its manufacturer, and installed as recommended in the user s instrument manual. 

Automated head space analyzer equi >ed with a flame ionization detector. Operating conditions are listed in Table 7.29. 

Morristown, NJ) for the ion source. No carrier gas separator was used. For determination of nitrosamines and TBDMS derivatives of hydroxy-nitrosamines, columns and operating conditions were identical to those for GC-TEA analyses For most work, the He flow rate was 15 cc/min and the column effluent was split 1 1 between a flame ionization detector and the mass spectrometer. The stainless steel splitter, solvent vent valve (Carle Instruments, Fullerton, CA), and associated plumbing were... 

The FID may be operated as an element-selective detector after minor modification. The hydrogen atmosphere flame ionization detector (HAFID) can be made selective towards organometalllc... 

The column is operated at 230°C using helium as a carrier gas at the rate of 60 ml/min. The retention time of the drug is approximately 4 minutes. A flame ionization detector is used. n-Triacontane is used as an internal standard. 

Fig. 14.7. —Schematic diagram of a capillary flame ionization detector showing the gas flows and components. Reprinted with permission from the 6890 Gas Chromatograph Operating Manual. Copyright (2004), Agilent Technologies.

There are three solution components, ethanol, acetone, and water. If a flame ionization detector is used, there will be only two peaks, since water will not give a peak Set up the instrument for isothermal operation at 100°C. The two peaks should be nicely resolved and each run should take only a few minutes. 

Some altitude effects on the operation of chromatographic instruments are anticipated. To achieve reproducible retention times for identifying compounds, mobile-phase flows need to be controlled so that they are independent of ambient pressure. Detectors may also respond to changes in pressure. For example, the electron capture detector is a concentration-sensitive sensor and exhibits diminished signal as the pressure decreases. Other detectors, such as the flame ionization detector, respond to the mass of the sample and are insensitive to altitude as long as the mass flow is controlled. 

GAS CHROMATOGRAPHY (METCALF (13)). Silanized glass columns 2 feet long, packed with 2% XE-60 on 80/100 mesh Gas Chrom Q, operating at 215°C, are used. The flame ionization detector is set at 230°C and the injection port at 230°C. 

GAS CHROMATOGRAPHIC ANALYSIS. The gas chromatograph was equipped (in the example used) with a flame ionization detector. Two stainless steel columns were packed with 5% SE-30 and 8% SE-52 on 60/80 mesh Chromasorb W-AW HMDS. The detector was maintained at 240°C and helium carrier was used at a flowrate of 3.5 cm3/min. Column temperature was programmed. The operator should determine the best rate of progression of temperature with the set-up in use. For example, one can start at 80°C and program at 4°/min up to 250°C. 

Gas Chromatography-Mass Spectrometry. A Hewlett-Packard Model 5890 Gas Chromatograph equipped with a hydrogen flame ionization detector was used in the study. A bonded phase DB-5 fused silica capillary column (30 m x 0.25 imi, 1 um film thickness) was used in all analyses (J W Scientific, Rancho Cordoba, CA). Operating parameters were as follows ... 

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