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采用热重-质谱法(TG-MS)和热解-气相色谱法(Py-MS)相结合的方法对模型化合物(十四硫醇、二丁基硫醚、苯硫醚、二甲基噻吩、苯并噻吩和二苯并噻吩等)在惰性气氛下硫的脱除及释放行为进行研究。惰性气氛下硫的脱除顺序为:十四硫醇>二丁基硫醚>二甲基噻吩>苯并噻吩>苯硫醚>二苯并噻吩,苯硫醚除外,该顺序与含硫官能团的热分解顺序一致。在热解过程中,所有模型化合物在质谱和气相色谱仪上均被检测到SO2;除苯硫醚和二苯并噻吩外,其他模型化合物中均检测到了COS;而只在十四硫醇、二丁基硫醚和二甲基噻吩中检测到了H2S。且热解气中SO2含量要显著高于H2S和COS。这是由于活性炭作载体时,惰性气氛下内部氢的含量显著小于内部氧的含量,所以大多数的含硫自由基易与内部氧结合以SO2的形式逸出。对于苯硫醚、苯并噻吩和二苯并噻吩中没有检测到H2S,是由于内部氢的不足,使得含硫自由基不能与内部氢结合,所以没有检测到H2S逸出。
The compounds of the model compounds (tetradecanethiol, dibutylsulfide, phenylsulfide, dimethylthiophene, dimethylthiophene, dimethylthiophene, , Benzothiophene and dibenzothiophene, etc.) under inert atmosphere sulfur removal and release behavior were studied. The sequence of sulfur removal under inert atmosphere is: tetradecanethiol> dibutylsulfide> dimethylthiophene> benzothiophene> phenylsulfide> dibenzothiophene, except for phenylsulfide, which differs from sulfur-containing functional groups The thermal decomposition of the same order. During pyrolysis, all the model compounds were detected as SO2 on mass spectrometry and gas chromatograph. COS was detected in all other model compounds except thiophenol and dibenzothiophene. However, H2S was detected in dibutyl sulfide and dimethylthiophene. And SO2 content in pyrolysis gas is significantly higher than that of H2S and COS. This is because when activated carbon is used as a carrier, the content of internal hydrogen in the inert atmosphere is significantly smaller than the content of the internal oxygen, so most of the sulfur-containing radicals easily combine with the internal oxygen to escape as SO2. No H2S was detected for the phenyl sulfide, benzothiophene and dibenzothiophene due to the lack of internal hydrogen so that the sulfur-containing radicals could not be bound to the internal hydrogen, so no H2S evolution was detected.