ARS | Publication request: The combined application of impinger system and permeation tube for the generation of volatile organic compound standard gas mixtures at varying diluent flow rate

Submitted to: Sensors
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: August 2, 2012
Publication Date: August 8, 2012
Citation: Susaya, J., Kim, K., Cho, J., Parker, D.B. 2012. The combined application of impinger system and permeation tube for the generation of volatile organic compound standard gas mixtures at varying diluent flow rate. Sensors. 12:10964-10979.

Interpretive Summary: Commercial standard gas generators are complex and expensive devices used to generate trace gases for calibrating air quality instruments used for odor and chemical emissions analyses. Concentrations in the parts per million to parts per billion ranges are achieved by adjusting the temperature or air flow rate across the permeation tube. A simplified standard gas generator was constructed by placing permeation tubes inside a temperature-controlled glass container. The temperature of the container was controlled using an electronic thermometer and water bath. The performance of the standard gas generator was assessed with four chemical compounds across a range of air flow rates. The simplified standard gas generation system produced gases of comparable quality to the more expensive commercial device.

Technical 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, ethylebenzene, m-xylene; BTEX) at varying flow rates (FR) of 50 to 800 mL/min. Because actual permeation rate (PR) values deviated from those computed by the manufacturer’s formula, new empirical relationships were developed to accurately estimate the PR of the target components. Experimental results corrected by such formula were reliable with high reproducibility (relative standard error: RSE <10%), while such patterns generally became more stabilized with increasing flow rate. The optimized datasets obtained from this impinger standard gas generation system were comparable to those derivable by a more delicate standard gas generation system with the high price.