Flame ionization detector performance

Purity. Gas chromatographic analysis is performed utilizing a wide-bore capillary column (DB-1, 60 m x 0.32 mm ID x 1.0 //m film) and a flame ionization detector in an instmment such as a Hewlett-Packard 5890 gas chromatograph. A caUbration standard is used to determine response factors for all significant impurities, and external standard calculation techniques are used to estimate the impurity concentrations. AHyl chloride purity is deterrnined by difference. 

For selective estimation of phenols pollution of environment such chromatographic methods as gas chromatography with flame-ionization detector (ISO method 8165) and high performance liquid chromatography with UV-detector (EPA method 625) is recommended. For determination of phenol, cresols, chlorophenols in environmental samples application of HPLC with amperometric detector is perspective. Phenols and chlorophenols can be easy oxidized and determined with high sensitivity on carbon-glass electrode. 

Gas chromatography analysis was performed on a Hewlett Packard GC Model 5890 equipped with a flame ionization detector and automatic injector 7673A. 

The photocatalytic experiments were performed in a horizontal quartz tube which it have TiOi. Illumination was provided by 500 W mercury lamps, located above the horizontal quartz tube. The reactant was 0.1% (v/v) ethylene in air. In case of Photo-Catalyst test, reactor effluent samples were taken at 30 min intervals and analyzed by GC. The composition of hydrocarbons in the feed and product stream was analyzed by a Shimadzu GC14B (VZIO) gas chromatograph equipped with a flame ionization detector. In all case, steady state was reached within 3 h. 

The activity tests of the catalyst were carried out in a microflow reactor set-up in which all the high temperature parts are constructed of hastelloy-C and monel. The reactor effluent was analyzed by an on-line gas chromatograph with an Ultimetal Q column (75 m x 0.53 mm), a flame ionization detector, and a thermal conductivity detector. The composition of the feed to the reactor can be varied, besides the temperature, pressure, and space velocity. The influence of the recycle components CHCIF2 and methane was tested by adding these components to the feed. In total five stability experiments of over 1600 hours were performed. In each... 

ECD = electrochemical detection FID = flame ionization detector GC = gas chromatography HPLC = high performance liquid chromatography M = molar NaOH = sodium hydroxide NR = not reported rpm = revolutions per minute... 

GC analysis for methanol, 1-propanol, 1-butanol, pyrrolidine, N-methylpyrrolidine, 2-pynolidinone, N-methyl-2-pyrrolidinone, gamma-butrolactone, dimethylsuccinate, and N-butyl-2-pyrrolidinone was performed with a Hewlett-Packard Model 5890 Gas Chromatograph equipped with a 30-meter, 0.53 mm I.D., 0.50-micron film, Nukol capillary column (Supelco, Bellefonte, PA) and a flame ionization detector (FID). 

Activities of the catalysts were measured on a microreactor. About 3 g of catalyst was charged into a reactor and heat-treated in nitrogen at reaction temperature. Acetic acid was added to the process and the reaction was initiated by switching nitrogen to ethylene. Reaction product analyses were performed by an online gas chromatograph equipped with a flame ionization detector (Perkin Elmer Auto System II). 

Performance aspects of volatiles organics analysis by purge and trap capillary column gas chromatography with flame ionization detectors has been discussed by Westendorf [71]. 

Elimination of wet chemical sample preparation enables a complete analysis to be performed and data to be quickly analyzed. The detection limits are in the low part-per-million range using mass spectrometric detection. Alternatively, detection of compounds can be achieved by all common gas chromatography detectors (flame ionization detector, electron capture detector and flame photometric detector), and detection limits are determined by the method of detection employed. 

Another difficulty in the gas chromatographic separation of amino acids is the choice of detector and it may be necessary to split the gas stream and use two different detectors. The flame ionization detector, which is commonly used, is non-specific and will detect any non-amino acid components of the sample unless purification has been performed prior to derivatization. In addition the relative molar response of the flame ionization detector varies for each amino acid, necessitating the production of separate standard curves. As a consequence, although gas chromatography offers theoretical advantages, its practical application is mainly reserved for special circumstances when a nitrogen detector may be useful to increase the specificity. 

High-performance liquid chromatographic separation with electrochemical detection may provide the best sensitivity for phenol quantification in biological samples. The use of gas chromatography with a flame ionization detector may be a more versatile method, if other non-ionic pollutants must be quantified. The advantages and disadvantages of different methods available for the quantification of phenol and metabolites in biological and environmental samples have been discussed by Tesarova and Packova(1983). 

ECO = electron capture detector ED = electrochemical detector FID st flame ionization detector GC = gas chromatography HECD = Hall s electrolytic conductivity detector HPLC = high performance liquid chromatography MEC = molecular emission cavity analysis MS - mass spectrometry HD = photo-ionization detector... 

The conversion of acetophenone to acetophenone cyanohydrin and enantiomeric excess were determined by gas chromatographic analysis after product derivatisation as the trifluoroacetate. GC was performed using a Chiraldex capillary GC column (G-PN -y-Cyclodextrin, Propionyl) from Astec using a CP3800 (Varian) with a flame ionization detector. Carrier gas was helium at 2 mL min . Temperature gradient 80 °C for 0.5 min, raise at 10.8°C min to 130 °C and hold 130 °C for 15 min. The injector and detector temperamres were set to 250 °C. 

GC = gas chromatography FID = flame ionization detector HPLC = high performance liquid chromatography HRGC high resolution gas chromatography MS = mass spectrometry RSD = relative standard deviation UV = ultraviolet light... 

The amount of cresol in the concentrated extract can then be determined by high performance liquid chromatography (HPLC) (DeRosa et al. 1987 Yoshikawa et al. 1986) or gas chromatography (GC) coupled to either a flame ionization detector (FID) or a mass spectrometer detection system (Angerer 1985 Needham et al. 1984). Separation of the cresol isomers by gas chromatography is readily accomplished, and the use of an appropriate internal standard allows the determination of their concentrations. Although exact detection limits were not given for the above GC methods, a concentration of 10 ppm appears to be readily determined. 

Total ethanol may be determined by gas chromatography using a Stabilwax (polyethylene glycol) column with helium carrier gas under isothermal (35°C) conditions [8], Analyte detection is performed using with a flame ionization detector [8]. The level of ethanol is typically 6 % w/w. 

The gases exiting the reactor pass through a Beckman 565 infrared CO2 analyzer, which continuously monitored the production of carbon dioxide. Gas composition analysis was performed on-line using a Hewlett Packard 5890 II gas chromatograph, equipped with both a thermal conductivity and a flame ionization detector and a Porapak-Q column. Additional experimental details are given elsewhere (9). 

The assay was carried out using a Varian gas chromatograph (model 5000 LC) under the following experimental condition. The oven injector and flame ionization detector temperatures were 125°C and 225°C respectively. A Porapak column was used, the eluent was N2 at a flow rate of 30 ml/min and the injected volume 2 pi. Various concentrations of purified methylene chloride in purified methanol were injected (both solvents were distilled to discard any impurity which might interfere with the sensitive assay). Calibration curves were linear in the range 50-500 ppm (the limit of detection was 10 ppm). Methylene chloride detection in the microspheres was performed by dissolving various amounts (20-200 mg) of microspheres in 220 ml of purified methanol prior to the injection. 

The GC was calibrated using a mixture of known quantities of d-limonene, d-limonene oxide (cis and trans), 2-octanone, and carvone. GC analyses were performed by injecting 1 pi samples with 1 40 split (column flow split flow), into a Hewlett-Packard 5840A GC equipped with a flame ionization detector. A fused silica capillary column 50m x 0.25 mm i.d., coated with OV-101 as a liquid phase was used. Column temperature was programmed from 50-250 C at 10 C/min, and helium was used as the carrier gas. 

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