Study on the Determination of NO,AsH3,COS and Other Impurities in Cracked Gas by Chromatography/Mass Spectrometry Method
裂解气中NO,AsH_3,COS等杂质的色/质联用测定研究

The selected ion monitoring(SIM) mode of capillary column gas chromatography coupled with mass spectrometry has been used for the determination of NO, AsH 3, COS, thio ether, thio alcohol etc in gases from catalytic cracking of heavy oils The interference of CO, CO 2, ethylene, ethane and N 2 which affected the determination of NO was eliminated by chromatographic separation and subtraction of responses The interference to the determination of selected ion was studied Only C\-2H\-5SH was affected at m/z =62 and the interference could be eliminated by using the ions at m/z =47 The impurities in practical sample gas were determined The detection limit of NO was 100 nL/L The detection limits of other impurities were between 15 nL/L and 50 nL/L.