Dry reforming of methane is an attractive process because it uses two important greenhouse gases, CO₂ for CH₄, to produce valuable syngas. However, Ni-based catalysts are prone to a high carbon deposition in the dry reforming process. Mesoporous LaNi_1-xMn_xO₃ perovskite (with x between 0 and 1) were synthesized by ultrasonic spray pyrolysis method. The substitution of Mn in the perovskite structure increased the specific surface area (from 7.2 for LaNiO₃ to 22.4 for LaNi_0.4Mn_0.6O₃), the pore size and pore volume. Temperature programmed reduction showed a lower reduction tendency of Mn-substituted samples, suggesting high structural stability. O₂- temperature-programmed desorption showed significantly higher oxygen mobility as the result of partial Mn substitution. The Mn substitution improved the catalytic activity and stability, where LaNi_0.6Mn_0.4O₃ achieved the highest conversion and remained relatively unchanged in the time on stream tests. The Mn substituted catalysts substantially decreased the carbon deposition and changed its form from whiskers to amorphous type. The XPS analysis suggests this change is due to the reversible transformation of Mn⁴⁺ and Mn³⁺, resulting in higher oxygen mobility. Microstructural characterization of the used catalyst revealed a lower sintering tendency for the Mn substituted catalysts than LaNiO₃. Results suggest that Mn substitution significantly changed the catalytic mechanisms, where LaNiO₃ removes carbon by forming La₂O₂CO₃ intermediate, but the stable Mn substituted perovskite with high oxygen mobility and capacity removes the carbon through a cyclic redox mechanism.

甲烷的干重整是一种有吸引力的方法，因为它使用了两个重要的温室气体，CO ₂为CH ₄，以产生有价值的合成气。但是，Ni基催化剂在干重整过程中倾向于高碳沉积。通过超声喷雾热解法合成了介孔LaNi _1-x Mn _x O ₃钙钛矿（x在0和1之间）。钙钛矿结构中Mn的取代增加了比表面积（从LaNiO _3的7.2到LaNi _0.4 Mn _0.6 O _3的22.4），孔径和孔体积。程序升温还原表明锰取代样品的还原趋势较低，表明结构稳定性高。由于部分Mn取代，O _2-程序升温脱附显示出更高的氧迁移率。Mn取代提高了催化活性和稳定性，其中LaNi _0.6 Mn _0.4 O ₃达到最高转化率，并且在流动测试时间中保持相对不变。Mn取代的催化剂大大减少了碳沉积，并将其形式从晶须变为无定形。XPS分析表明，这种变化是由于Mn ⁴⁺和Mn ³⁺的可逆转变引起的，导致更高的氧气迁移率。所用催化剂的微观结构表征表明，Mn取代催化剂的烧结趋势低于LaNiO ₃。结果表明，Mn取代显着改变了催化机理，其中LaNiO ₃通过形成La ₂ O ₂ CO ₃中间体除去碳，而具有高氧迁移率和容量的稳定Mn取代的钙钛矿则通过循环氧化还原机理除去了碳。