ZrO_2助剂对费-托合成Co/SiO_2催化剂失活过程中结构变化的影响(英文)

Effect of ZrO_2 Promoter on Structural Change of Co/SiO_2 Catalyst During Its Deactivation in F-T Synthesis

采用X射线衍射和X射线吸收精细结构表征手段对ZrO2改性前后的Co/Si O2催化剂在费-托合成过程中因结构变化而失活进行了研究.不同失活程度的催化剂通过在常压微型固定床反应器中调节反应环境分压比p(H2O)/p(H2)进行的一系列模型实验来获得.结果表明,Co0晶粒的氧化和长大均可导致Co/Si O2催化剂失活,在高的水分压条件下,氧化是主要的失活原因.在相同条件下,经ZrO2改性的Co/Si O2催化剂的失活可以得到明显抑制,催化剂稳定性显著提高.

Cobalt-based catalysts supported on SiO2 have been applied in Fischer-Tropsch synthesis （FTS） for the production of liquid fuels and chemical stocks from coal or natural gas. ZrO2 is an effective promoter to improve the stability of Co-based catalysts and enhance the yield of heavy hydrocarbons. However, the way that ZrO2 influences the structural changes of cobalt catalysts during FTS is rarely reported. To provide insight into the ZrO2 promoter, a series of model experiments were performed using the partial pressure ratio of P（H2O）/P（H2） as the key variable that affects deactivation of the catalysts.