Temperature programming chromatography

The gases used were purchased premixed in aluminum cylinders to avoid carbonyl formation. The high purity gas mixture was further purified by a zeolite water trap and a copper carbonyl trap. The gas pressure in the reactor was measured with a capci-tance manometer and the fTow monitored with a mass fTow controT-ler. The typical gas flow rates were 15 cc/min (STP) and the maximum conversion was 1% based on integration of hydrocarbon products. The hydrocarbon products were analyzed by gas chromatography (temperature programmed chromosorb 102, FID). 

Specialized Techniques Used in Gas Chromatography Temperature Programming... 

Temperature program and isothermal operation are complementary separation techniques in gas chromatography. Temperature program operation is used for the separation... 

Van Den Dool, H. and P.D. Kratz (1963), Generalization of the retention index system including linear temperature programmed gas-liquid partition chromatography . J. Chromatogr, Vol. 11, p. 463. 

Figure 12.22 SFC-GC analysis of aromatic fraction of a gasoline fuel, (a) SFC trace (b) GC ttace of the aromatic cut. SFC conditions four columns (4.6 mm i.d.) in series (silica, silver-loaded silica, cation-exchange silica, amino-silica) 50 °C 2850 psi CO2 mobile phase at 2.5 niL/min FID detection. GC conditions methyl silicone column (50 m X 0.2 mm i.d.) injector split ratio, 80 1 injector temperature, 250 °C earner gas helium temperature programmed, — 50 °C (8 min) to 320 °C at a rate of 5 °C/min FID detection. Reprinted from Journal of Liquid Chromatography, 5, P. A. Peaden and M. L. Lee, Supercritical fluid chromatography methods and principles , pp. 179-221, 1987, by courtesy of Marcel Dekker Inc.

The purity of 1 and 2 is assessed by analytical gas-liquid chromatography (GC) on a Hewlett-Packard 5890 gas chromatograph equipped with a flame-ionization detector and fitted with a 50 m x 0.2 mm HP-5 fused silica glass capillary column using linear temperature programming from an initial temperature of 150°C for 5 min to a final temperature of 200°C for 10 min at a rate of 5°C/min. 

Chromatography Hewlett-Packard Ultra2 (25 m x 0.33 mm) cross-linked phenyl methyl silicone fused silica capillary column. Temperature program 55° (1 min.) -I- 30°C/min. to 180°C, and 4°C/min. to 320°C. 

Jaglan PS, Gunther FA. 1970. Single column gas liquid chromatography of methyl parathion and metabolites using temperature programming. Bull Environ Contam Toxicol 5 111-114. 

Marutoiu C, Sarbu C, Vlassa M, et al. 1986. A new separation and identification method of some organophosphorus pesticide by means of temperature programming gradient thin-layer chromatography. Analysis 14 95-98. 

Halang, W. A., Langlais, R., and Kugler, E., Cubic Spline Interpolation for the Calculation of Retention Indices in Temperature-Programmed Gas-Liquid Chromatography, Ana/. Chem. 50, 1978, 1829-1832. 

The separation nuaber is the only column efficiency par2uaeter that can be deterained under teaperature progr2uued conditions [45,46]. The critical parameters that aust be standardized to obtain reproducible SM values for coluans of different length are the carrier gas flow rate and the temperature program. The SN is widely used as part of a standardized test method to evaluate the quality of open tubular columns for gas chromatography (section 2.4.3). 

The temperature program mode is the most widely used separation technique in gas chromatography [155]. As well as reducing separation times for samples with a wide tailing point... 

Chiu, G., Separation of carboxylic acids by temperature programmed liquid chromatography, /. HRC CC, 9, 410, 1986. 

Temperature-programmed packed capillary liquid chromatography (TP-CLC), coupled off-line to solvent elimination FTIR (LC Transform ) has recently been used for gradient separations of Irganox 1010/1076/3114 dissolved in DMF with LOD of about 40 ng [511]. Low... 

Figure 7.27 Constructed Gram-Schmidt chromatogram of a temperature-programmed packed-capillary LC separation of 4.8 ig Irgafos P-EPQ dissolved in DMF temperature programme 50°C for 8min, 4°Cmin-1 up to 140°C. Legend 1, mono-P-EPQ 2, Irgafos 168 3, 4,3 -P-EPQ 4, oxidised 4,4 -P-EPQ 5, 4,4 -P-EPQ. After Bruheim et al. [511]. From I. Bruheim et al., Journal of High Resolution Chromatography, 23, 525-530 (2000). Wiley-VCH, 2000. Reproduced by permission of Wiley-VCH.

Davis, J.M. (2004). Assessment by Monte Carlo simulation of thermodynamic correlation of retention times in dual-column temperature programmed comprehensive two-dimensional gas chromatography. J. Sep. Sci. 27, 417. 

Venkatramani, C.J., Xu, J., Phillips, J.B. (1996). Separation orthogonality in temperature-programmed comprehensive two-dimensional gas chromatography. Anal. Chem. 68, 1486. 

The reaction products were analyzed on-line by gas liquid chromatography (Varian 3400) on a 50 m CPSil-5 capillary column from Chrompack, hydrogen being the carrier gas (15 psi), with a temperature programming from 45 to 170°C (5°C.min 1) then from 170 to 180°C (2°C.mm1). 

Boylan and Tripp [76] determined hydrocarbons in seawater extracts of crude oil and crude oil fractions. Samples of polluted seawater and the aqueous phases of simulated samples (prepared by agitation of oil-kerosene mixtures and unpolluted seawater to various degrees) were extracted with pentane. Each extract was subjected to gas chromatography on a column (8 ft x 0.06 in) packed with 0.2% of Apiezon L on glass beads (80-100 mesh) and temperatures programmed from 60 °C to 220 °C at 4°C per minute. The components were identified by means of ultraviolet and mass spectra. Polar aromatic compounds in the samples were extracted with methanol-dichlorome-thane (1 3). 

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