Effect of lattice oxygen in nickel-based catalysts with different support on coke resistance of filamentous coke in CO₂ reforming of tar

For CO₂ reforming of tar, deactivation of catalysts caused by filamentous coke deposition limits its application in solid waste treatment. The filamentous coke removal can be aided by the lattice oxygen of active mental sites, however, there is no information on the influence of lattice oxygen in catalyst support on filamentous coke oxidation. To investigate the activity and resistance to coke deposition of different catalysts, based on a comparison of the performance of Ni/ZrO₂, Ni/SiO₂, Ni/MgO, and Ni/attapulgite catalysts, the influence of lattice oxygen on filamentary coke deposition is investigated in this study. In CO₂ catalytic reforming experiments, the Ni/ZrO₂ catalysts showed higher coke conversions (10%–23%) than the Ni/SiO₂, Ni/MgO, and Ni/attapulgite catalysts. In the meantime, the lattice oxygen coverage of the Ni/ZrO₂ superficies reaches 55.59%, giving Ni/ZrO₂ a better resistance to filamentary coking. The high lattice oxygen coverage also improves the oxidation of the coke superficies by lattice oxygen. However, there was still 31.66% filamentary coke aggregation on the Ni/ZrO₂ catalyst superficies. In conclusion, inhibiting the formation of filamentous coke and promoting the oxidation of filamentous coke are key to improving the efficiency of CO₂ reforming of anaerobic tar. The results of the research can be used as a reference for the improvement of catalysts.针对焦油的二氧化碳重整反应，丝状积碳沉积导致的催化剂失活问题，限制了该技术在固体废物处理领域的应用。丝状积碳的脱除可借助活性金属位点的晶格氧实现，但目前尚无关于催化剂载体晶格氧对丝状积碳氧化过程影响的相关研究报道。为探究不同催化剂的反应活性与抗积碳性能，本研究以Ni/ZrO₂、Ni/SiO₂、Ni/MgO及凹凸棒石（attapulgite）负载镍催化剂的性能为对比基础，考察了晶格氧对丝状积碳沉积过程的影响。在二氧化碳催化重整实验中，Ni/ZrO₂催化剂的积碳转化率（10%~23%）高于Ni/SiO₂、Ni/MgO及凹凸棒石负载镍催化剂。与此同时，Ni/ZrO₂表面的晶格氧覆盖率可达55.59%，使其具备更优异的抗丝状积碳性能。较高的晶格氧覆盖率同样可促进晶格氧对积碳表面的氧化作用。但即便如此，Ni/ZrO₂催化剂表面仍存在31.66%的丝状积碳团聚体。综上，抑制丝状积碳的生成并促进其氧化，是提升厌氧焦油二氧化碳重整反应效率的关键所在。本研究结果可为后续催化剂的改性优化提供参考依据。

搜集汇总

背景与挑战

背景概述

该数据集研究了镍基催化剂中晶格氧对焦炭抵抗性的影响，重点关注CO2重整焦油过程中不同载体（如ZrO2、SiO2、MgO和凹凸棒土）的催化剂性能。研究发现，Ni/ZrO2催化剂具有更高的晶格氧覆盖率（55.59%）和焦炭转化率（10%-23%），表现出更好的抗丝状焦炭沉积能力，为催化剂改进提供了参考。