Identification of control parameters for the sulfur gas storability with bag sampling methods

Department of Environment & Energy, Sejong University, Seoul 143-747, Republic of Korea.
Analytica chimica acta (Impact Factor: 4.51). 08/2012; 738:51-8. DOI: 10.1016/j.aca.2012.06.010
Source: PubMed


Air samples containing sulfur compounds are often collected and stored in sample bags prior to analysis. The storage stability of six gaseous sulfur compounds (H(2)S, CH(3)SH, DMS, CS(2), DMDS and SO(2)) was compared between two different bag materials (polyvinyl fluoride (PVF) and polyester aluminum (PEA)) at five initial concentrations (1, 10, 100, 1000, and 10,000ppb). The response factors (RF) of these samples were determined after storage periods of 0, 1, and 3 days by gas chromatography-pulsed flame photometric detector (GC-PFPD) combined with an air server (AS)/thermal desorber (TD) system. Although concentration reduction occurred more rapidly from samples of the high concentration standards (1000 and 10,000ppb), such trends were not evident in their low concentration counterparts (1, 10, and 100ppb). As such, temporal changes in RF values and the associated loss rates of most sulfur gases were greatly affected by their initial concentration levels. Moreover, the storability of oxidized sulfur compound (SO(2)) was greatly distinguished from that of reduced sulfur compounds (RSCs), as the former almost disappeared in the PVF bag even after one day. The results of our study confirm that storability of gaseous sulfur species is affected interactively by such variables as initial gas concentration level, bag material type, and oxidation status with the associated reactivity.

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Available from: Sang-Hee Jo, May 18, 2015
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    • "The mitigation and control of these RSCs are important due to their well-known strong malodourous properties , even typically at sub-ppb concentration levels (Nagata, 2003). Sulfur compounds have varying degrees of deleterious effects on human health, if they are present above certain threshold values (Jo et al., 2012; Prasad, 2013). For instance, DMDS can be toxic if inhaled or adsorbed through the skin. "
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