Abstract The stable nickel catalyst for CO2 reforming of methane (DRM) is an indispensable requirement for boosting the efficiency of methane conversion to synthesis gas. Herein, without using the regularly ordered porous support, neodymium-promoted nickel catalysts were synthesized by co-precipitation method (denoted as NixNd1-x catalysts, Ni/Nd = 1:9, 3:7, 5:5, 7:3 and 9:1). By regulating the Nd and Ni loadings, the nickel species in the reduced NixNd1-x catalysts could be controlled. When the Ni/Nd molar ratio was in the range of 3/7 to 7/3, NiNd2O4 predominantly existed on the catalyst surface. Once the Ni/Nd mole ratio exceeded this range, Ni species surface was covered by thick amorphous Nd2O3. The activity during DRM was studied as a function of temperature (550–800 °C) and time on stream (750 °C, 24 h). Although carbon deposition increased with the nickel loading, the produced carbon did not block the porous structure in the spent Ni5Nd5 and Ni7Nd3 catalysts. A fraction of the nickel segregating on the spent catalyst surface to become the active site ensured Ni5Nd5 and Ni7Nd3 catalysts having the most active and stable catalytic performance. The activity results correlated well with the higher surface area of the starting NixNd1-x catalysts, the smaller Ni crystallite sizes, and structural reconstructions during the DRM reaction.

中文翻译：

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钕镍氧化物复合催化剂上甲烷CO2重整的性能和稳定性

摘要 稳定的用于甲烷 CO2 重整 (DRM) 的镍催化剂是提高甲烷转化为合成气效率不可或缺的条件。在本文中，不使用规则有序的多孔载体，通过共沉淀法合成了钕促进的镍催化剂（表示为 NixNd1-x 催化剂，Ni/Nd = 1:9、3:7、5:5、7:3 和9:1）。通过调节 Nd 和 Ni 的负载量，可以控制还原的 NixNd1-x 催化剂中的镍物种。当 Ni/Nd 摩尔比在 3/7 到 7/3 的范围内时，NiNd2O4 主要存在于催化剂表面。一旦 Ni/Nd 摩尔比超过此范围，Ni 物质表面就会被厚厚的非晶 Nd2O3 覆盖。DRM 期间的活性被研究为温度（550-800°C）和运行时间（750°C，24 小时）的函数。尽管碳沉积随着镍负载量的增加而增加，但产生的碳并没有堵塞废 Ni5Nd5 和 Ni7Nd3 催化剂中的多孔结构。一部分在废催化剂表面分离成为活性位点的镍确保了 Ni5Nd5 和 Ni7Nd3 催化剂具有最活性和最稳定的催化性能。活性结果与起始 NixNd1-x 催化剂的较高表面积、较小的 Ni 微晶尺寸以及 DRM 反应过程中的结构重建密切相关。