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The combined application of impinger system and permeation tube for the generation of volatile organic compound standard gas mixtures at varying diluent flow rates.

Kim KH, Susaya J, Cho J, Parker D - Sensors (Basel) (2012)

Bottom Line: The performance of the impinger standard gas generation system was assessed for four aromatic VOCs (benzene, toluene, ethylbenzene, and m-xylene; BTEX) at varying flow rates (FR) of 50 to 800 mL·min(-1).Experimental results corrected by such a formula indicate that the compatibility between the APR and MPR generally increased with low FR, while the reproducibility was generally reduced with decreasing flow rate.Although compatibility between different PRs is at a relatively small and narrow FR range, the use of correction formula is recommendable for the accurate use of PT.

View Article: PubMed Central - PubMed

Affiliation: Department of Environment & Energy, Sejong University, Seoul 143-747, Korea. khkim@sejong.ac.kr

ABSTRACT
Commercial standard gas generators are often complex and expensive devices. The objective of this research was to assess the performance of a simplified glass impinger system for standard gas generation from a permeation tube (PT) device. The performance of the impinger standard gas generation system was assessed for four aromatic VOCs (benzene, toluene, ethylbenzene, and m-xylene; BTEX) at varying flow rates (FR) of 50 to 800 mL·min(-1). Because actual permeation rate (APR) values deviated from those computed by the manufacturer's formula (MPR), new empirical relationships were developed to derive the predicted PR (PPR) of the target components. Experimental results corrected by such a formula indicate that the compatibility between the APR and MPR generally increased with low FR, while the reproducibility was generally reduced with decreasing flow rate. Although compatibility between different PRs is at a relatively small and narrow FR range, the use of correction formula is recommendable for the accurate use of PT.

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Comparison of BTEX data (ng·mL−1) between the AC and MC as a function of diluent flow rate (mL·min−1). Labels: MC = manufacturer given concentration; AC = actual measured concentration; and PC = predicted concentration using our developed equations.
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f2-sensors-12-10964: Comparison of BTEX data (ng·mL−1) between the AC and MC as a function of diluent flow rate (mL·min−1). Labels: MC = manufacturer given concentration; AC = actual measured concentration; and PC = predicted concentration using our developed equations.

Mentions: As described above, we already defined three different types of concentration terms such as MC, AC, and PC. Because of differences in concentration data derived between different terms, their values are presented to allow comparison with each other (Table 4). Plots of AC values for each compound against FR exhibited curvilinear patterns (Figure 2). A strong inverse relationship between AC and diluent FR was observed for benzene (R2 = 0.9285). However, the relationships for T, E, and X were not as strong, with R2 values of 0.5286, 0.0346, and 0.2066, respectively. These measured concentration (AC) values of BTEX were compared with those calculated using equations of the manufacturer (MC) at each specific flow rate at 25 °C. In case of B and E, AC values were comparable with MC at lower FR (e.g., <100 mL·min−1) but deviated considerably with increasing FR (Figure 2). However, the pattern of deviation between MC and AC changed greatly from each other.


The combined application of impinger system and permeation tube for the generation of volatile organic compound standard gas mixtures at varying diluent flow rates.

Kim KH, Susaya J, Cho J, Parker D - Sensors (Basel) (2012)

Comparison of BTEX data (ng·mL−1) between the AC and MC as a function of diluent flow rate (mL·min−1). Labels: MC = manufacturer given concentration; AC = actual measured concentration; and PC = predicted concentration using our developed equations.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472869&req=5

f2-sensors-12-10964: Comparison of BTEX data (ng·mL−1) between the AC and MC as a function of diluent flow rate (mL·min−1). Labels: MC = manufacturer given concentration; AC = actual measured concentration; and PC = predicted concentration using our developed equations.
Mentions: As described above, we already defined three different types of concentration terms such as MC, AC, and PC. Because of differences in concentration data derived between different terms, their values are presented to allow comparison with each other (Table 4). Plots of AC values for each compound against FR exhibited curvilinear patterns (Figure 2). A strong inverse relationship between AC and diluent FR was observed for benzene (R2 = 0.9285). However, the relationships for T, E, and X were not as strong, with R2 values of 0.5286, 0.0346, and 0.2066, respectively. These measured concentration (AC) values of BTEX were compared with those calculated using equations of the manufacturer (MC) at each specific flow rate at 25 °C. In case of B and E, AC values were comparable with MC at lower FR (e.g., <100 mL·min−1) but deviated considerably with increasing FR (Figure 2). However, the pattern of deviation between MC and AC changed greatly from each other.

Bottom Line: The performance of the impinger standard gas generation system was assessed for four aromatic VOCs (benzene, toluene, ethylbenzene, and m-xylene; BTEX) at varying flow rates (FR) of 50 to 800 mL·min(-1).Experimental results corrected by such a formula indicate that the compatibility between the APR and MPR generally increased with low FR, while the reproducibility was generally reduced with decreasing flow rate.Although compatibility between different PRs is at a relatively small and narrow FR range, the use of correction formula is recommendable for the accurate use of PT.

View Article: PubMed Central - PubMed

Affiliation: Department of Environment & Energy, Sejong University, Seoul 143-747, Korea. khkim@sejong.ac.kr

ABSTRACT
Commercial standard gas generators are often complex and expensive devices. The objective of this research was to assess the performance of a simplified glass impinger system for standard gas generation from a permeation tube (PT) device. The performance of the impinger standard gas generation system was assessed for four aromatic VOCs (benzene, toluene, ethylbenzene, and m-xylene; BTEX) at varying flow rates (FR) of 50 to 800 mL·min(-1). Because actual permeation rate (APR) values deviated from those computed by the manufacturer's formula (MPR), new empirical relationships were developed to derive the predicted PR (PPR) of the target components. Experimental results corrected by such a formula indicate that the compatibility between the APR and MPR generally increased with low FR, while the reproducibility was generally reduced with decreasing flow rate. Although compatibility between different PRs is at a relatively small and narrow FR range, the use of correction formula is recommendable for the accurate use of PT.

Show MeSH
Related in: MedlinePlus