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利用程序升温测硫技术(TPSD) 对自制的和一些工业的钴钼耐硫变换催化剂中硫的存在状态、作用等进行了研究。结果表明: (1) 负载在γ-Al2O3 上的Mo 的硫化物较未负载Mo 的硫化物或98% MoS2 易与氧、氢和水蒸气反应, 载体不仅可提供大的反应表面, 而且活化了与Mo 相联的硫原子; (2) 负载在γ-Al2O3 上的Co 不能被硫化, 但是当Mo/γ-Al2O3 中加入Co 后, 与Mo 相联的硫变得更加活泼, 更易与氧、氢和水蒸气反应, 可见Co 与Mo 作用减弱了S-Mo 键的强度; (3) Co-Mo/γ-Al2 O3 中加入K 后, 催化剂中的硫很难与氢反应, 但易与水蒸气反应; (4) 几乎所有的硫化物催化剂, 包括工业催化剂, 在与氧、氢和水蒸气反应过程中,其TPSD-O2 谱图在200~280℃和400~470℃温区均有硫峰出现;(5)硫化物催化剂热稳定性不好的原因是催化剂经高温处理后,低温活性位不可逆地转变为高温活性位;(6)提出了硫化物催化剂上水煤气变换反应的机理, 硫在催化过程中起着十分重要的作用。
The existence state and function of sulfur in self-made and some industrial cobalt-sulfur sulfur-tolerant shift catalysts were studied by TPSD. The results show that: (1) The sulfide of Mo supported on γ-Al2O3 reacts more easily with oxygen, hydrogen and water vapor than the unsupported Mo sulfide or 98% MoS2. The support not only provides a large reaction surface, but also activates (2) Co supported on γ-Al2O3 can not be vulcanized, but when Co is added to Mo / γ-Al2O3, the sulfur associated with Mo becomes more active and more likely to react with oxygen, Hydrogen and water vapor reaction, we can see the role of Co and Mo weakened the S-Mo bond strength; (3) Co-Mo / γ-Al2 O3 added K, the catalyst is difficult to react with hydrogen sulfur, Vapor reaction; (4) Almost all sulfide catalysts, including commercial catalysts, have TPSD-02 spectra of sulfur at temperatures of 200-280 ° C and 400-470 ° C during reaction with oxygen, hydrogen and water vapor Peak appears; (5) The reason why the thermal stability of the sulfide catalyst is not good is that the catalyst is subjected to high temperature treatment , The low temperature active site irreversibly converted into a high temperature active site; (6) the proposed mechanism of sulfide catalyst of the Water Gas Shift Reaction, sulfur plays an important role in the catalytic process.