Chromatographic Method for the Concentration of Trace Impurities in the Atmosphere and Other Gases

Novák, Josef; Vašák, V.; Janák, J.

doi:10.1021/ac60225a008

Cited by 72 publications

(8 citation statements)

References 4 publications

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“…At a given temperature, any vapor diluted in a gas stream continually flowing through the tubing will be quantitatively adsorbed inside the trap until the total sample volume is equal to the retention volume of the studied substance at this temperature, less the half-base width of the particular peak obtained for this compound in elution analysis (Figure 4). When this volume is reached, the gas and the adsorbent are in equilibrium for the corresponding substance, no more trapping occurs, and the system operates according to the Novak and coworkers' method (Novak et al, 1965). For trimethvl phosphate, we have determined (Raymond and Guiochon, 1973) that the maximum sample volume for quantitative trapping in one of our graphitized carbon black tubing is 6.5 liters at 25°C.…”

Section: Resultsmentioning

confidence: 99%

Gas chromatographic analysis of C8-C18 hydrocarbons in Paris air

Raymond¹,

Guiochon²

1974

Environ. Sci. Technol.

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Section: Resultsmentioning

confidence: 99%

Gas chromatographic analysis of C8-C18 hydrocarbons in Paris air

Raymond¹,

Guiochon²

1974

Environ. Sci. Technol.

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“…Either the volume of air sampled is restricted such that no breakthrough of the compounds of interest occurs, or sampling is continued far beyond initial breakthrough and an equilibrium concentration of each hydrocarbon is retained on the adsorbent. 127 The collected compounds are eluted from the porous polymer at an elevated temperature into an inert gas stream. Since elution is a rather slow process, the hydrocarbons must be Downloaded by [University of Waterloo] at 06:25 04 November 2014 condensed in a cooled tube, and then subsequently flash vaporized into the gas chromatograph.…”

Section: Specific Hydrocarbonsmentioning

confidence: 99%

Recent Advances In Air Pollution Analysis

Harrison¹,

Stevens²

1984

C R C Critical Reviews in Analytical Chemistry

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“…The adsorption of gaseous compounds to sorbent materials by chromatographic equilibration is widely applied, e.g. for the determination of toxic volatile organic compounds (VOCs) [1], trace impurities [2,3] and studies on pollutants in the atmosphere [4][5][6][7][8][9] or other gaseous samples. For sampling, the sampled gas (i.e.…”

Section: Introductionmentioning

confidence: 99%

“…Individual components are trapped according to their partition coefficients, inversely related to their volatility [4]. Indeed, in a sorption system the maximum possible sample volume enabling optimal analyte recovery is inversely related to the volatility of a component; therefore, the most volatile component in a mixture usually delimits the maximal sample volume [2]. When the equilibrium zone is expanded through all the sorbent bed length and the capacity of the sorbent tube is exceeded, the volatiles leave the material and breakthrough occurs [9].…”

Section: Introductionmentioning

confidence: 99%

Challenges of fast sampling of volatiles for thermal desorption gas chromatography - mass spectrometry

Marcillo

Weiß

Widdig

et al. 2020

Journal of Chromatography A

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Fast active sampling of volatile organic compounds (VOCs) under field conditions still is a great challenge especially when the exposure time to the source of emissions is a restricting factor. Hence, to identify ideal conditions for such applications, we systematically compared fast active sampling of VOCs collected on two common adsorbents under two regimes: first, very low gas volumes (from 300 mL) sampled at nominal flow rate and, second, sampling at the maximal applicable flow rate (0.5 L/min) before loss of sorbent material was experienced. For XAD-2 and Tenax TA, efficient sorbents for on-site VOC-sampling followed by thermal desorption GC-MS, significant differences in the signal response of volatile compounds were related not only to the varied experimental factors alone, but also to their interactions and to compound volatility. In the first regime, volatiles (~ 0.004-3.13 mM) from Tenax TA gave the highest signal response only above 800 mL sampled gas volume while at low concentrations (~ 0.004-0.12 mM), satisfactory recovery from XAD-2 required longer analyte-sorbent interaction. For the second regime, the relative recovery was severely impaired down to 73 ± 23 %, n=56 for Tenax TA and 72 ± 17 %, n=56 for XAD-2 at equimolar intermediate concentration, and 79 ± 11 %, n=84 for Tenax TA at high concentration compared to the relative recovery at standard flow rate. Neither Tenax TA nor XAD-2 provided a 100% total recovery (calculated using breakthrough values) for any of the evaluated compounds. Finally, two-way and three-way interactions identified in a multi-variable model, explained not only the dependence of the signal response on different experimental variables, but also their complex interplay affecting the recovery of the VOCs. In conclusion, we show for the first time that XAD-2, a material only recently introduced for the adsorption of volatiles from the gas phase, competes well with the standard material Tenax TA under conditions of fast sampling. Due to the similar absolute recovery with Tenax TA even at low concentration and with regard to the better detection limits, we consider XAD-2 the better choice for fast sampling of VOCs, particularly with low sample volumes at regular flow. For fast sampling with high flow rate, however, both sorbents might be selected only if the corresponding recovery loss can be accepted for the study.

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Chromatographic Method for the Concentration of Trace Impurities in the Atmosphere and Other Gases

Cited by 72 publications

References 4 publications

Gas chromatographic analysis of C8-C18 hydrocarbons in Paris air

Gas chromatographic analysis of C8-C18 hydrocarbons in Paris air

Recent Advances In Air Pollution Analysis

Challenges of fast sampling of volatiles for thermal desorption gas chromatography - mass spectrometry

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