Enhanced coke-resistant Co-modified Ni/modified alumina catalyst for the bireforming of methane

Abstract

Biogas has been highlighted as a renewable energy and local source for syngas production via reforming techniques to combat global warming effects and energy sustainability. The bireforming of methane is one of the most suitable processes for utilizing biogas as it provides a syngas (H₂/CO) ratio of about 2, which is suitable to couple with downstream processes such as methanol and Fischer–Tropsch synthesis for the generation of liquid hydrocarbons. Metal–support interactions, surface acidity–basicity properties, and particle sizes play a pivotal role in reforming reactions. Herein, high surface area alumina was used with dopants ceria and magnesia, aiming to tune up the surface basicity and oxygen storage properties of the support. Over this, uniformly dispersed Ni and Co nanoparticles were synthesized via the deposition precipitation method. The doping of ceria and magnesia tuned the basicity of the support and showed an improved oxygen storage capacity favoring the inhibition of coke deposition and promoting catalyst activity and stability. The Ni–Co synergy not only provides a steady and excellent activity with conversion rates of 97% and 89% for CH₄ and CO₂ but also inhibits coke formation during 500 h long-term activity analysis.