In this study, the calibration characteristics of six new odorant VOCs along with two reference compound were evaluated based on GC-MS (SIM). For the proper evaluation of the GC/MS method, calibration of 7 VOCs were made both by the SPME and direct injection (DI). The minimum detection limit (MDL) of those VOC determined by SPME method fell in the range of 0.31∼0.38 ppb while those of DI from 6.18∼14.3 ppb.
The analytical performance of our SPME/GC-MS method was compared against those tested previously by other study groups. Although more efforts are needed to establish the reliability of our SPME/GC-MS method, the method adapted in this study can be recommended as one of the standard methods for the analysis of the target VOCs in this study to settle formal experiment methods.
In this study, we attempt to analyze for 4 compounds (MEK, MIBK, n-Butyl acetate, i-Butyl alcohol) in ambient air using on-line thermal desorber (on-line TD) with gas chromatograph/flame ionization detector (GC/FID). These compounds will be regulated by KMOE (Korean ministry of environment) within 2010. We tested two different experimentation. First, we try to find the influence of Nafion dryer for the 4 compounds. Second, we want to know basic analytical characteristic of target compounds through the linearity, reproducibility, and minimum detection limit. According to this study, target compounds are removed in Nafion dryer more than 80 percent, respectively. So, we progressed next experimentation progressed without Nafion dryer using hydrophobic cold trap. Results for each compounds showed good linearity (r²=0.99 upper) and good precision (RSD=1 % below). In additional, we analyzed the ozone precusors standard gas (56 compounds) using the same method to see if there are any peaks to be overlapped in ambient air. These results showed that there is no peak overlapped. This means that analytical system of this study could be used on-line analytical system. Minimum detection limit (MDL) value for this system are less than minimum malodor threshold concentration.