[Photooxidation of CS2 under ambient pressure and vacuum condition]

With the radiation of UV light, the photooxidation of CS2 was studied under ambient pressure and vacuum condition. By means of in-situ FTIR, XPS and GC-MS, it is confirmed that the products of the reaction are COS, SO2, CO and CO2. The reaction is apparent first-order. Under ambient pressure and vacuum condition the concentration of the intermediate product COS varies tremendously. Under ambient pressure the concentration of COS increases sharply and then decreases gently. While under vacuum condition COS rose only up to 1/10 that of the ambient pressure, and remained invariable until finally vanished slowly. Under ambient pressure and vacuum condition, the half life time of CS2 was 31.6 s and 39.8 s, and it took 55 min and 22 min to degrade 98% of COS respectively. Oxygen promotes CS2 photooxidation. The main products of the photooxidation of COS, which is an important intermediate of the photooxdiation of CS2, are CO2 and SO2. In addition, SO2 could be further oxidized into SO2(4-). Increasing appropriate amount of oxygen could promote the photooxidation activity of COS. However, the rate constant remains invariable when the oxygen is overloaded.