Detectors hydrogen atmosphere flame ionization

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... 

DuPuis MD and Hill HH Jr. 1979. Analysis of gasoline for antiknock agents with a hydrogen atmosphere flame ionization detector. Anal Chem 51 292-295. 

HAFID Hydrogen atmosphere flame ionization detector HCOT Helically coiled open tubular (column)... 

Osman et al reported the analysis of a mixture of n-hydro-carbons and n-alcohols. The alcohols were converted to their trimethyls ilyl derivatives with Tri-Sil Z and the mixture was chromatographed on two different instruments, one equipped with a standard flame ionization detector and the other with the third design of the silicon sensitive hydrogen atmosphere flame ionization detector. 

Dupuis and Hill have demonstrated the use of a hydrogen atmosphere flame ionization detector (HAFID) 48-452 modified from a commercial FID as a selective gas chromatographic detector for the determination of organolead compounds in gasoline. By a simple one to ten dilution of a leaded gasoline, alkyllead compounds were detected with no interference from overlapping chromatographic peaks of hydrocarbons. Detection limits were calculated to be 7.3 x 10"" g/s of lead. 

DePuis and Hill have described a method for the determination of methylcyclopentadienylmanganese in amounts down to 1.7 x 10 g/s of manganese. In this work they used a hydrogen atmosphere flame ionization detector (HAFID) modified from a commercial FID. The apparatus is described in detail in the section on organolead... 

The gas phase hydrogenation of acetonitrile has been studied in a differential microflow reactor operating at atmospheric pressure. Prior to any measurements, the sample was reduced under a diluted hydrogen flow (H2/N2 10/90, vol/vol) at 723 K for 2h (ramp 2 K min i). The reaction temperature ranged from 343 to 453 K, and the H2/acetonitrile molar ratio was 6.8. The effluent was analyzed by sampling on line to a gas chromatograph (Perkin Elmer) equipped with a capillary column (30 m x 0.25 mm i.d., apolar phase) and a flame ionization detector. 

The hydrogenation reaction of methyl benzoate was carried out at atmospheric pressure in a flow reactor at 300 and 350°C. The catalysts (0.1 g) were first activated at 350°C under pure H2 for 2 h. Then methyl benzoate (P = 2.7 Torr) was carried from a thermostated regulator in the H2 flow (flow rate 40 ml.min i). The reaction products were analysed by an on line gas chromatograph equipped with a capillary column and a flame ionization detector. 

Its basic design can be compared to a standard flame ionization detector modified so that oxygen enriched air is premixed with the column effluents and introduced through the jet tip while hydrogen doped with small amounts of silane is introduced directly into the detector housing so that the flame burns in a hydrogen atmosphere. 

Monitoring of hydrocarbons in atmospheric samples takes advantage of the very high sensitivity of the hydrogen-flame-ionization detector to measure this class of compounds. Known quantities of air are run through the flame-ionization detector 4-12 times per hour to provide a measure of total hydrocarbon content. 

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