Ni catalysts for dry methane reforming prepared by A-site exsolution on mesoporous defect spinel magnesium aluminate

Abstract

In dry methane reforming, the selection of a suitable support is critical due to coke formation and metal particle sintering. We prepared two types of mesoporous defect spinel magnesium aluminate support, namely DS09, with a Mg/Al molar ratio (Mg/Al) of 0.1, and DS19 with Mg/Al = 0.24. Each support has a high surface area, large mesopore volume, and a phase between its defect spinel (Mg0.388Al2.408O4) and spinel (MgAl2O4) structures. Magnesium aluminate with a Mg/Al of 0.5 (MG30), which has a low surface area and is devoid of mesopores, was used as the reference support. Ni was supported on DS09 (Ni-DS09) and DS19 (Ni-DS19) by A-site ex-solution. These catalysts display significant advantages over Ni-supported MG30 (Ni-MG30); Ni-DS19 exhibited a higher coke resistance than Ni-DS09, due to its lower acidity, while DS19, which contains a defect spinel structure, optimized acidity, and well-developed mesopores, was the best support for the DMR.