Ni-based catalysts supported on ZrO₂ and SBA-15 were employed in dry reforming of methane. The relation between carbon deposition and the deactivation of supported Ni catalysts was studied. Ni/ZrO₂ exhibited superior stability, despite of its high coking rate. Therefore, there was no direct relationship between the coking rate and the deactivation rate. In order to investigate the nature of the coke species during dry reforming of methane, TG-DTA/CO₂-TPO/TPSR/TEM experiments were conducted on the spent catalysts. Characterization results showed that the formation of CNTS on Ni/ZrO₂ could be responsible for the superior stability. For comparison, the dominant carbon species was encapsulating carbon on Ni/SBA-15, leading to serious deactivation. The main difference between Ni/ZrO₂ and Ni/SBA-15 was the reactivity of carbon species towards carbon dioxide. Coke deposited on Ni/ZrO₂ was oxidized by CO₂ at lower temperature, although carbon species on the two catalysts was similar. Additionally, the results of TPSR illustrated that the surface oxygen species over the zirconia support was involved in the oxidation of coke by CO₂. The activity of Ni/ZrO₂ was completely restored after the in-situ regeneration with CO₂, indicating that carbon deposition was greatly removed by CO₂.

中文翻译：

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Ni / ZrO 2和Ni / SBA-15在甲烷干重整中碳沉积特征的比较

负载在ZrO ₂和SBA-15上的Ni基催化剂用于甲烷的干重整。研究了碳沉积与负载型Ni催化剂失活之间的关系。Ni / ZrO ₂尽管具有高的焦化率，但仍表现出优异的稳定性。因此，焦化率和失活率之间没有直接关系。为了研究甲烷干重整过程中焦炭种类的性质，对用过的催化剂进行了TG-DTA / CO ₂ -TPO / TPSR / TEM实验。表征结果表明在Ni / ZrO ₂上CNTS的形成可能是出色的稳定性的原因。为了进行比较，主要的碳物种将碳封装在Ni / SBA-15上，从而导致严重的失活。Ni / ZrO ₂和Ni / SBA-15之间的主要区别是碳物质对二氧化碳的反应性。尽管两种催化剂上的碳种类相似，但沉积在Ni / ZrO ₂上的焦炭在较低的温度下被CO ₂氧化。另外，TPSR的结果表明，氧化锆载体上的表面氧物种参与了CO ₂对焦炭的氧化。用CO ₂原位再生后，Ni / ZrO ₂的活性完全恢复。，表明碳沉积被CO ₂大大去除了。